New Year, New Man

 Therefore if any man be in Christ, he is a new creature: old things are passed away; behold, all things are become new. (2 Corinthians 5:17)

Since we are on the verge of the new year 2016, and 2015 is about to pass away, this seemed like an appropriate passage for New Year's Eve. This verse also happens to be a favorite of mine. One reason is because it is one of those verses that has shown itself to be so helpful. In a world plagued by false conversions and false professions of faith, it is one of those foundational verses which help us discern not only the truth of other people's faith, but even more importantly, our own.

Of course you might ask, what exactly does it mean for a person to be "in Christ" as the verse phrases it. Perhaps the best answer is found in John chapter 15. Jesus, speaking to his disciples, said this.

I am the true vine, and my Father is the husbandman. Every branch in me that beareth not fruit he taketh away: and every branch that beareth fruit, he purgeth it, that it may bring forth more fruit. Now ye are clean through the word which I have spoken unto you. Abide in me, and I in you. As the branch cannot bear fruit of itself, except it abide in the vine; no more can ye, except ye abide in me. I am the vine, ye are the branches: He that abideth in me, and I in him, the same bringeth forth much fruit: for without me ye can do nothing. (John 15:1-5) 

This metaphor compares us to branches on a vine that is Jesus Christ. The branches depend upon the vine for sustenance, just as a Christian depends on God's word. The branches of a vine are the means by which the vine bears its fruit, just as the Christian is Jesus' chosen way of building his kingdom. In other words, the person who is abiding in the vine, or in Christ, is the genuine believer.

Of course 2 Corinthians 5:17 is not the only place we find that speaks of one who is "in Christ" as being a new creature.

In Ephesians 4 we read this:

But ye have not so learned Christ; If so be that ye have heard him, and have been taught by him, as the truth is in Jesus: That ye put off concerning your former manner of life the old man, which is corrupt according to the deceitful lusts; And be renewed in the spirit of your mind; And that ye put on the new man, which after God is created in righteousness and true holiness. (Ephesians 4:20-24)

Now, since the Christian is commanded to put off the old man and put on the new, it may lead one to believe that this becoming a new creature, is an act of your own will. That is true at least on one level, for from our point of view it is a matter of deciding to do, and then to do it. However, the other side of that coin can be found in Paul's letter to the Philippians where he says this: For it is God which worketh in you both to will and to do of his good pleasure. (Philippians 2:13)

In other words, it is God who works in you to change your will so that you want to do what pleases him. God doesn't force you, the Christian, to do things you don't want to, but in his grace and mercy he gently and imperceptibly changes your will, so that it conforms to his will. The results of this change in your will, which we might call the new creature, is found in numerous places in scripture, among them Ephesians 4 where we just left off a moment ago.

Wherefore putting away lying, speak every man truth with his neighbour: for we are members one of another. Be ye angry, and sin not: let not the sun go down upon your wrath: Neither give place to the devil. Let him that stole steal no more: but rather let him labour, working with his hands the thing which is good, that he may have to give to him that needeth. Let no corrupt communication proceed out of your mouth, but that which is good to the use of edifying, that it may minister grace unto the hearers. And grieve not the holy Spirit of God, whereby ye are sealed unto the day of redemption. Let all bitterness, and wrath, and anger, and clamour, and evil speaking, be put away from you, with all malice: And be ye kind one to another, tenderhearted, forgiving one another, even as God for Christ's sake hath forgiven you.
(Ephesians 4:25-32)
The bottom line is that for the true Christian, at some point in their life there will have been a change. They will have become a new creature. Their old way of life will have passed away. Everything will have become new including their desires. They will desire to please God rather than fulfill the lusts of the flesh. If you have never experienced such a change and the concept is foreign to you, it should be a matter of grave concern. In Paul's letter to the church of Corinth he urges them: Examine yourselves, whether ye be in the faith; prove your own selves. Know ye not your own selves, how that Jesus Christ is in you, except ye be reprobates? (2 Corinthians 13:5)

We began with this text: "Therefore if any man be in Christ, he is a new creature: old things are passed away; behold, all things are become new."

Have you examined yourself in light of this scripture?

Doug Wilson's Night Before Christmas

Couldn't help but share this poem by Doug Wilson.  If you choose to pass it along, please be sure to give proper credit to the author.

‘Twas the night before Christmas and all through the land,

We still mark the birth of the One who is banned

From public discussion or public display.

"Get rid of the Christ child–but still keep the day!"

So public school children must practice with stealth

Those carols which threaten our strange commonwealth,

And now and again someone’e runaway creche

Will abruptly appear in some government place,

Right out in the open where children can view

This threat to the folks at the ACLU.

So drink to the health of our once happy nation,

And deck all the halls with strange litigation.

Then eat all you want to, drink rum by the quart

But don’t say that name, or you’ll wind up in court.

Pretend that this holiday just always was.

Don’t ask whence it came like a smart child does.

Just talk about Rudolph or Santa’s small elves,

Or sing little ditties of days bunched in twelves.

Now this is all right because (please get this straight)

There’s no separation of North Pole and state.

So sing all you want of this sort of stuff

In the public arena, folks can’t get enough.

If you do sing the carols, then please, just be careful.

Look over your shoulder, keep watch and be prayerful.

Edit those carols, avoid our law’s curses,

(You’ll have to leave out quite a few of the verses.)

So you won’t get the secular humanists riled

With songs about sinners and God reconciled.

"Be near me Lord Jesus, I ask Thee to stay,"

Angers the People for the Humanist Way.

But if you believe the time is now ripe

To stand up for Christmas, don’t sit there and gripe.

The secular Scrooges and Grinches will hear

If you say, "Merry Christmas," with all the right cheer.

It’s time to be counted for what’s good and right,

To all, Merry Christmas! To all, a good night!

Do Muslims and Christians Worship the Same God?

Apparently this is a question that is gaining some attention recently by way of a multitude of articles posted on the Internet.  I must admit that I was not aware of such articles, until I watched (listened to, actually) this video by James White, who I always find to be edifying.  Dr. White, as usual, seems to have hit the nail right on the head, where so many of us often hit it a glancing blow resulting in a bent nail.

For the whole story, I recommend watching the 24 minute video, but here is my condensed and paraphrased version of White's points:

Historically Muslims and Christians are talking about the same God, but that is not the same as worshiping the same God. Mohamed and the Muslims say that Allah is the God of Abraham. Christians also claim to follow the God of Abraham.

The New Testament says that "the hour cometh, and now is, when the true worshippers shall worship the Father in spirit and in truth" 

However the author of the Koran seemed to believe that the Trinity worshiped by the Christians consisted of God the Father, Mary the wife and Jesus the son.  That is an excusable mistake considering that by Mohamed's day there were already local sects that had gone off the rails and were bowing down to statues of Mary (just as the church of Rome still does to this day). 

This is where the rubber meets the road.  Islam denies that God has a son.  Christianity confirms what is revealed about the deity of Christ in the Bible.  The Koran would seem to equate worshiping Jesus as God with an unforgivable sin.   If God is who the New Testament reveals him to be, then those who deny the Trinity cannot be true worshippers.  Likewise, if the New Testament is wrong and the Koran correct, then Christians cannot be worshipping in truth.  I must add though, it does seem a little strange that if "Allah" was going to correct the record about a Trinity that the Christians were mistakenly worshipping, he wouldn't have "clued in" his prophet as to the actual identity of the members of the Trinity.





















 

Action

I had every intention of posting a short explanation of why I took the liberty of putting the name "YaHWeh" in place of "the LORD" when quoting Psalm 100 in my post for Thanksgiving.  However while researching it I realized that , as so often happens, it was not just a simple, cut and dried topic.  ...and yes, since you ask, I do make a habit of researching most of what I write rather than just "shooting from the hip" (despite how it might appear).  In any case, the explanation will have to wait for me to find a little more free time to formulate an intelligible post, but in the meantime I do have this:

This picture, snapped by an unknown photographer, is from the second pass I made on the Knuckledragger at the Meltdown Drags this summer.  The amount of air between the front wheel and the pavement was not really in the script, but it makes for an great action shot.

BTW, in the past couple weeks this photo seems to have made the rounds on the Internet.  When I first became aware of it, I made some inquiries as to its origin, hoping to thank the photographer and formally ask permission to reproduce it, but came up empty handed.  If anyone can point me in the right direction I would still like to do that.

Giving Thanks 2015

Thanksgiving. Is it a meal, or is it a holiday? Or is it a holiday known for its meal? Or is it just possibly, for some, an attitude?

I am afraid that for the majority of Americans, Thanksgiving Day is no different than any other day of the year in respect to their treatment of the Creator of the universe. In other words, there will be little or no thought given to the one who gives us everything. Oh, perhaps a grandpa or an uncle who grew up when life was different will bow his head and give thanks for the meal at the family get together, but that is about it. Many will not even hear those words because they are so intent on the feast that follows.

In fact, the politically correct way to celebrate Thanksgiving is to say you are thankful for blessings all the while being careful not to mention to who it is that you are thankful. That way random chance gets just as much glory as the King of kings and Lord of lords.

But, I would like to offer a suggestion for this Thanksgiving Day. Let's give thanks where thanks is due. Let's try to adopt the attitude displayed in the following:

Make a joyful noise unto YaHWeH, all ye lands.
Serve YaHWeH with gladness: come before his presence with singing.
Know ye that YaHWeH he is God: it is he that hath made us, and not we ourselves; we are his people, and the sheep of his pasture.
Enter into his gates with thanksgiving, and into his courts with praise: be thankful unto him, and bless his name.
For YaHWeH is good; his mercy is everlasting; and his truth endureth to all generations.Psalm 100

This is a replay of a post I wrote in 2010.  I add this note at the end, rather than the beginning, in the hope that I have tricked you into reading it a second time. 

Valve Stem Protrusion, Part 2: The Knucklehead

　
Now that you have been introduced to the basics of valve stem protrusion specification and how they pertain to Panheads and Shovelheads, let's go back to the beginning, so to speak, and look at what most would concede to be Harley's first modern OHV engine, the Knucklehead.

Time to "fess up." The question of the valve stem protrusion specification for a Knucklehead is one I have never been able to come up with a definitive answer to, and I have been pondering it for about 30 years. Apparently the factory did not feel it was important enough to publish (at least anywhere I have been able to find) or just overlooked it.

One of the figures I've seen offered (it was on the Internet, so it must be true!) is that the factory spec was 1.575-1.580" measuring from the shoulder on the guide to the tip of the valve. While this may be correct, no source was cited. Did it come from a factory drawing or was it info passed on from someone's step-uncle who once heard it from a guy who knew someone who worked on Harleys a lot under a shade tree in the back yard to supplement the income from his day job changing tires and doing oil changes at the local Texaco station?  Either way, this spec, to be accurate, would need to take into account the differences in the thickness between stock and reproduction gaskets that go under the lower spring cup. I cannot be sure what the OEM gasket thickness was, but from supplier to supplier I have seen as much as .030" difference in the thickness. Then if you use 2 gaskets under the intakes as the manual calls for, you have doubled any error. Incidentally, if the factory was able to hold a .005" tolerance on valve stem protrusion in the '30s and '40s, they were doing far better than what is seen from them today (admittedly a very real possibility).

Another of the "specs" I have seen given (also on the Internet, so it also must be true!) for Knuck stem protrusion is 15/16" above the top of the valve guide for the exhaust and 7/8" for the intake. Even if a source for that info was given, it would be meaningless without the dimensions of the OEM guide top.  The guides available today are not even the same shape as the originals above the flange, let alone the same height.  True as it may have been at one time, it is about as useful as giving directions to a stranger that include the phrase "turn left where farmer Smith's big red barn used to be."

One other "spec" I have seen published in a recent book, also without a source quoted, is intake 1.525" minimum/1.570" maximum and exhaust 1.575" minimum/1.620" maximum. That would also suffer from being at the mercy of gasket thickness.

I also tend to think that any stem protrusion "spec" that is given with intake and exhaust being different one from the other is probably suspect, because that would mean that without shimming, the spring installed height and seat pressure would be different intake to exhaust. I am quite sure valve spring shims were not factory installed.  My guess is that those "specs" were extrapolated due to the difference in overall valve length on Knuckles, intake verses exhaust.  Either that, or valve seat pressure difference intake to exhaust was considered acceptable by the factory.  The difference of .050" of installed height would work out to about 16 pounds more seat pressure on the intakes if KPMI's stock replacement springs are indeed made to exact OEM spec as advertised.  That is probably within the realm of possibility also, but again I would like to see a source.

And speaking of extrapolation, or my best guess if you prefer, here is my theory:

There is a chart on page 82 of the Panhead Service Manual 1948-1957 Rigid that lists specs for 18204-36 inner and 18203-36 outer OHV springs. Those would be the stock springs for a Knucklehead.  The chart lists a compressed length of 1.40625" for the outer spring under a column labeled "valve closed" along with a "valve open" length of 1.0625".  That leads me to believe that the 1.406 figure would be within the acceptable range for spring installed height. Adding the lift of a stock cam, which the same manual lists as .343" for a Knuckle on page 89, to the open height of 1.0625" gives 1.4055" which matches the 1.40625" after allowing for rounding up or down.  Now, the question becomes, does this spring installed height reflect a minimum or maximum valve stem protrusion, or is it somewhere in the middle?

Back to that table of specs.  According to it, the "Knuck" springs (we'll call them -36 springs from here on out) were used on all overhead valve engines (read: Knuck and Pan) except FLH (the higher compression 74"). That reveals a bit of a discrepancy hidden in the specifications.  Since the same valves, collars and keepers were used for both FL and FLH Panheads, it is safe to say that the -36 springs could safely be installed at the same height as the stronger FLH spring set, especially given the fact that there is no separate stem protrusion spec given for Panheads, FL versus FLH.  But the "valve closed" spring height for the FLH spring is 1.375 rather than the 1.406 of the -36 spring.  That would put the acceptable spring installed height of both spring sets somewhere between those two figures.

Interestingly, if we give the 1.375 figure a +/- tolerance of .005" we come up with exactly the 1.370" to 1.380" recommended installed height for KPMI's "stock replacement" Knucklehead spring sets, which are claimed to be "manufactured to exact O.E.M specifications."

Now it happens that I have measured enough Knuck valves, springs and collars over the years to confidently say that the spring installed height on a Knuckle will be .200" less than the valve stem protrusion measured from the tip to the top of the lip on the guide.  That .200" figure is valid when using stock spring collars and valves with stock keeper groove location.  It is also subject to the slight variation resulting from manufacturing tolerances.  That means if we were to take the 1.370" spring installed height and add .200" to it, we could safely extrapolate (there's that word again) a 1.570" minimum valve stem protrusion.  If we then want to take a stab at a maximum stem protrusion, I would suggest the same .045" spread that the Pans and Shovels use, resulting in a maximum spec of 1.615". 

But remember now, while that may provide a stock stem protrusion spec (depending on whether you buy into the multiple assumptions and extrapolations which I have made or not), this will only get you to the correct valve spring installed height.   One still needs to take into account the discrepancy in thickness of the gaskets under the spring cups if you are really concerned with getting the valve to exactly the same relationship to the head and rocker arms as when it left the factory.  Back here in the real world, though, the effects of the gasket thickness on rocker geometry are minimal.

In fact, I would go back to what I presented in the previous stem protrusion post about how changes in valve lift affect theoretically correct rocker arm geometry. If you are running a stock lift cam, then you are done. As I mentioned, according to the Harley's service manuals, the lift of a Knuckle cam is .343".  If anyone is wondering about this seemingly odd number, just convert that figure into a fraction and you will see it was quite obviously a rounding off of 11/32" - over the years Harley has been very comfortable with the use of fractions in their design parameters.   Incidentally, if you notice that I have been playing fast and loose with the terms cam lift/valve lift here when writing about Knuckles, its because the 1:1 rocker ratio actually makes those figures interchangeable, unlike other OHV Big Twins.

But if you simply read cam manufacturer's literature you might not realize that the stock lift was only .343".  The Andrews "S" grind, which is advertised as a stock replacement for restorations is .355" lift.  Lieneweber's mildest Knuck cam, the "0", is still a bolt-in but has .365" lift.  Back when Sifton was Sifton, their only Knuck grind came in at a whopping .450" lift.  Our friends in Viola seem to be the only manufacturer who makes a true stock replacement grind (even if it is listed as .346" lift). 

Using my "theoretically correct rocker geometry" method of adding 1/2 the increase in valve lift over stock to the minimum and maximum stem protrusion specs, one can see that even the mild bolt in cams add a little wiggle room.  The 110 Sifton on the other hand, coming in at .106" more lift than stock adds a full .053" to the specs.  In other words, if you accept my extrapolation (had to get that word in one more time) your stem protrusion specs would go from 1.570" minimum/1.615" maximum, all the way to 1.623" minimum/1.668" maximum.  That would, of course, create other issues that would need to be addressed, such as spring pressure and installed height, not to mention top collar to rocker arm and cover clearances.  But all of that will need to wait for another post.

One last point.  the figures I present here are my best estimate based on the numbers we do find in various factory service manuals.  I will be happy to print a correction if someone can provide their source material for conflicting numbers, or provide reasoning that improves on my own.  By no means do I mean any sort of insult to those who have presented different figures.  It is entirely possible that the whole concept of minimum and maximum stem protrusion specs was not even on the factory's radar before the printing of the Panhead service manual, and was merely left to the common sense and/or whims of the re-builder.

And in case anyone is not yet sure, the word of the day was, as you probably guessed, "extrapolation."

Valve Stem Protrusion; Knucks, Pans, and Shovels

Harleys are very rebuildable, and I would go so far as to venture that they may be among the most commonly rebuilt (using the term "rebuilt"somewhat loosely) of any engine family in existence. Such a supposition is somewhat bold, given the minuscule number of Harleys compared to the vast oceans of, say, small block Chevys. But face it, which engine is more likely to wind up in a scrap yard when it is in need of major repair?

Given that, along with the often less than spectacular life span of a top end rebuild on Knuckles, Pans, Shovels and Sportsters, many if not most have seen multiple valve jobs over the decades. Naturally with each valve job performed, the valves will seat a little deeper in the head. The method of gauging how much deeper is via the valve stem protrusion specification. Valve stem protrusion is one of those specs that is sometimes overlooked and to some extent misunderstood when dealing with Harley heads.

At issue are a several things. In no particular order; valve spring installed height, shrouding of the valve in the chamber, compression ratio, and finally rocker arm geometry. Having less than the minimum can lead to the devastating result of your valve springs reaching coil bind while your cam is still trying to lift the valves higher. Not a good situation and can usually be summed up as 'broken parts."  On the opposite end of the spectrum is the Panhead that looks as though the pan covers have been bashed out with a ball peen hammer (because they have indeed been bashed out with a ball peen hammer) so that the valve spring collars would not hit them.

Shrouding of the valve in the chamber from the valve being too deep is fairly easily remedied by a judicious modification of the chamber during the process of a valve job, though this too can overdone resulting in issues down the road when new seats are installed.  Along with deep valve seats comes a reduction in compression ratio (aggravated via de-shrouding) by making the chamber larger.  That may or may not be an issue depending on a number of factors.

Valve train geometry is also at issue, but I will attempt to address that later in the post.

To examine this subject I would like to start in the middle and work our way forward in time before going back to the beginning - that beginning being the Knucklehead.

On page 75 of the Harley Davidson Panhead Service Manual - 1948-1957 Rigid, we find what seems to be first official mention of the specification (at least that I can find).

The spec, which the drawing refers to as "Valve Seat Tolerance" is pretty self explanatory. It is the distance from the tip of the valve stem to top surface of the collar of the valve guide. The illustration also shows a gauge which was available for those lacking precise measuring tools or for quick checks. The gauge is simply a cylinder that straddles the guide. The "step" at the top of the gauge indicates minimum and maximum height; if the tip of the stem falls between the top and bottom of the notch, the stem protrusion is within spec.

The 1978-1/2 to 1984 FL/FX 1200/1340 4 Speed Service Manual (note the title may not be growing in length but it certainly is in use of numbers) shows the same illustration (page 3-18) for 1979 and earlier, but it might be worth noting that it offers a different illustration and spec for 1980 and later.

The difference, at least in part, is due to the changeover to valve guide seals. Earlier heads, both Pan and Shovel, only required a machined pad that was at least the diameter of the valve guide collar to locate the guide since the lower spring collar rested on the collar of the guide. The addition of seals made it necessary to rest the lower spring collar directly on the head to provide room for the seal, so the machined portion of the spring pocket was increased to the diameter of the lower spring collar.

Late vs Early

At first glance one might assume that the different spec is due to taking the measurement to a different surface, since it is now from the tip of the valve to the surface that the bottom of the guide collar seats against. And maybe that's the case, however, things don't seem to quite add up. If the collar on the guide is nominally .100" thick, then all is well. Add .100" to the early 1.500" to 1.545" spec and you come up with the '80 and later spec of 1.600 to 1.645". Ignoring the '80-'81 guides that used a .075" snap ring instead of having a guide with an integral collar, there is still the question of the gaskets that were under the guide collar on earlier motors. I had to look pretty close to even find the part number (18196-51) for this gasket in a Harley parts book since it does not appear in any later copies, though I have a small collection of them left over from top end kits. Measuring a random sample of these showed that they ranged in thickness from about .030" to .040". The James Gaskets catalog lists them as .031" thick with the application being 1951 to 1978.

Hmmm,... so with a window of only .045" in minimum and maximum stem protrusion, we find a variance of at least .030" just in whether or not a gasket was installed under the guide when rebuilding. And what about '48 to '50 Pans and '79 Shovels? Won't they show up as nearly at maximum protrusion right from the factory? And what does that mean when considering '80 and up which certainly never used the gasket? Now the .100" difference in stem protrusion spec doesn't add up so neatly because you have an "effective" guide collar thickness of .130" (collar + gasket) for many years.

Add all of this together and I think its safe to conclude that stem protrusion specification is probably not something will "make or break" your valve job unless you wander too far afield. My guess is that the spec was added after the fact as a guideline for mechanics rather than a part of the original design parameters of the Motor Company.

And if all doesn't throw enough margin of error into the equation, then consider this. If the Motor Company's stem protrusion specs theoretically provide correct valve train geometry (and that is a gigantic stretch given shops such as Baisley High Performance have presumably made a fair chunk of money over the years from their service of correcting Harley rocker arm geometry), then that still means that when you increase valve lift via a performance cam, you have also changed the stem protrusion numbers which should theoretically retain correct geometry.

Here is basically how it works. If you were to draw one imaginary line through your pushrod and another through the rocker arm's ball socket to the center of the rocker shaft, when your cam is at one half of its lift, the line should form a 90 degree angle. Likewise, an imaginary line from the center of the rocker shaft to the pad of the arm should also form a 90 degree angle with the centerline of the valve stem at that same half lift point. That way at zero lift the line through your rocker arm should be the same amount below 90 degrees as it is above 90 degrees at full lift. But that means that if you increase the lift of the valve with no other changes, then the angle with the valve closed will remain the same , but the 90 degree relationship between pushrod and rocker will no longer be at 1/2 lift. To get back to the theoretically correct valve train geometry you would need to lengthen the valve by an amount equal to 1/2 the increase in lift. Or, you could get the same effect by sinking the valve that amount. And guess which is easier and more cost effective, sinking the valve or having a custom valve manufactured?

All of that is to say that with a performance cam, the theoretically correct stem protrusion increases at a rate of half the increase in valve lift. In practice this also has the added benefit on a Harley of providing the increased valve to valve clearance during overlap (commonly referred to as Top Dead Center lift) which is needed for those performance cams.

Now, with all that to digest, I'll pause briefly before continuing with the question of valve stem protrusion on a Knucklehead.  Stay tuned.

One Nation

Over the years, when contemplating such things as the Holocaust,  I have often wondered how the German people could stand by while such atrocities were perpetrated. Estimates are that more than 6 million Jews were killed over a 12 year period. Many of these met their fate at concentration camps such as Dachau, or in what may be more accurately called death camps such as Auschwitz or Chelmno.

I have often thought upon the stories of how the Allied forces, when they liberated the camps, forced the local citizens to go out to the camps and view the results of the great evil which they had allowed to take place.  Many of the locals expressed some level of horror, claiming they really didn't know what was taking place under the Nazis.  Still, I could never quite accept that, and would be left feeling that the people should have risen up against their government and come to the aid of their fellow human beings.  I could not help but think that if I had been in that position I would not have stood for it.  I'd have had to do something.  Conscience would have demanded it regardless of consequences.  Just what kind of depraved citizenry could allow such a thing to happen?

Fast forward 70 years.  The Jewish Holocaust only a painful memory.  Yes, there is a whole religion which simultaneously denies the first Jewish Holocaust while it preaches the need for a second, but we have not yet seen its implementation.  However, we are already in the midst of another holocaust involving even greater numbers and just as much evil.  If you can watch the following video and join your fellow countrymen in calmly sitting by and ignoring it, ...well, then it would appear that your conscience is already seared.

In our hearts and minds we cannot help but pass judgment on those citizens of Nazi Germany who turned their backs and ignored the evil which was happening in their midst.  But we should be careful to keep a mirror handy.

" For with what judgment ye judge, ye shall be judged: and with what measure ye mete, it shall be measured to you again." (Matthew 7:2)

Do you believe the German people individually bear some responsibility for their lack of action?  Then we bear some responsibility for our lack of action in our modern abortion holocaust.  Do you believe that the downfall of the Nazi government was a just reward for carrying out the Holocaust?  Then where does that leave our nation?

 

 

 

 

2015 Meltdown Lives Up to the Name

Not exactly what one might call "timely" but I thought a short report on the 2015 Meltdown Drags to be in order.  That it lived up to its name is an understatement.  Hot, humid, and more hot.

As per my plan, I spent a little time before the event putting together a 4 speed transmission for the Knuckledragger, and got it installed with about a day to spare.  The largest obstacle turned out to be the most expensive piece involved in building the transmission, that being a new reproduction ratchet lid.  Ratchet it did not.  Thankfully I caught the problem while "dry shifting" it before even putting it on the trany.  it would have been quite discouraging to get to the track only to be plagued by shifting problems once again.  As it was, all it cost me was a bunch of time to figure out and modify the part so that it would function.

Rather than traveling in style as we did for last year's event, this time around we went for practicality.  That means that in place transporting the Knuckledragger on an open trailer behind our '46 Studebaker, we put the bike in our small enclosed trailer and towed it with our '90 GMC pickup.  I guess one person's modern is  another's vintage.  Even our enclosed trailer took the opportunity to remind us just how old it is by shedding the tread from one its tires near Madison Wisconsin.  That's right, even our "modern" enclosed trailer is so old that the tires I remember buying for it nearly 20 years ago (because we wore out the first pair traveling all over the country to drag races) disintegrated due to age.  The good LORD was looking out for us though; and the tire never even lost air, allowing us to pull off the freeway to install the spare which I had remembered to air up at the last minute the night before.  A short detour to a Farm and Fleet store got us back on the road with a new pair of tires, delaying us just enough to insure we would not have time to make any passes on Friday.

Hard to believe this still held air!

Saturday morning dawned, well... hot.  A first look at the "vintage" three instrument set which I mounted to the back door of our trailer many years ago, revealed over 80 degrees and 75% humidity.  As the day went on, the humidity dropped some, but the temperature kept right on climbing, at one point breaking 100 in the shade of our canopy. But despite the heat it was time to fire up the Knuckledragger  for the first time since the 2014 Meltdown Drags.  So much for my wife's insistence that I absolutely must test the bike before hauling it all the way the Illinois ...

The start up revealed that the bike was running good.  The idle was higher than I remembered, but it was also seemed to be much more consistent, so I decided against messing with it.  The clutch was releasing nicely, and combined with the good idle characteristics, allowed me to take my right hand off the throttle to reach across the tank and put the transmission into gear.  Yes, that's right: a hand shift and a hand clutch, both on the left side.  That drew more than a couple puzzled glances over the weekend.

It starts, it runs, and it will go into gear.  Better make a pass!

As we brought the bike up to the staging lanes late that morning, I had two concerns.  One was the start and the other was the finish.  The 5 inch slick on the back of the Knuckledragger with its modern compound, combined with  extremely sticky track preparation courtesy of the Byron Dragway crew, is a recipe for wheelies.  Add to that the fact that the new transmission has a first and second gear, unlike the third and fourth in the old two speed it replaced, and I was a little concerned with how the bike would launch.  The second concern had to do with the finish.  Last year's lone trip down the 1/4 mile  plagued by shifting problems was not much of a test of the Knuckledragger's 1930s designed brakes.  I really prefer to be able to stop while still on the drag strip!



John Endrizzi was kind enough to help out with getting the bike to the line and all that entails

That first concern was solved rather easily by a combination of staging to the outside of the portion of the track that was heavily prepped.  Since the Byron dragstrip is unusually wide (in the 60s they would race the cars 4 abreast) there was still plenty of room between where I staged and the edge of the track.  As an added precaution I "drove" the bike off the starting line rather than launching it.  Once off the starting line, the bike went straight as I poured the coal to it. 

This and the previous photo were passed on to me by way of Kevin Baas.  Thank you to whoever took the pics and sent them to him.

The shift from first to second was exactly as it was supposed to be, fast and clean ...as was the shift to third and again to fourth!  Finally.  This was the first time in four outings that this bike had shifted properly.  But now my second area of concern was rapidly approaching.  In fact, it seemed to be approaching too rapidly!  About 200 feet from the finish line that concern turned into fear that I would not be able to get the bike stopped within the confines of the shut down area so  I shut the throttle and laid on the brakes.  Of course the rear drum brake coupled with the just barely "better than nothing" springer front brake does not give anything like the sensation of modern brakes, but I did get stopped with some room to spare.  12.228 seconds at 97.03 MPH.  The time slip shows the Knuckledragger was clipping along at over 91 MPH at half track so I have to wonder how fast it was traveling before I hit the brakes.

Something about high temperatures and humidity is not conducive to putting on a helmet and a full set of leathers.  It was apparent that the heat was also limiting the number of cars getting into the staging lanes also.  About mid afternoon I decided that if I did not get up there for another pass, I would be too worn out from the heat to do it at all. 

This time I did not concern myself as much about the starting line, staging a little more into the sticky part of the track (though still far from where I would have if looking for maximum hook up).  That was probably a mistake.  I left just slightly harder than the previous pass, which sent the front wheel reaching for the sky.  Well, at least from my viewpoint it was high, but such things can be deceptive when you are lying down on a bike.  Unfortunately my staff photographer had just finished helping with the whole starting the bike drill and had no time to get in position to record it for posterity, so we may never know just how far the front wheel came up.  In any case, rather than shutting the throttle and slamming the front end down, I eased off enough that it came down with a reasonable amount of gentleness, and then immediately came back up as I got back into the throttle.  The second wheelie was a much more half hearted effort on the Knuckledragger's part though, not requiring me to let off.  Once again, this description is from my perspective.  If ever any video evidence surfaces, it may reveal that I handled the wheelies with far less professionalism than what it felt like from behind the bars.

Despite an abysmal 60 foot time owing to the acrobatics, the shift into second was good, but then at the top of second gear the motor started to break up.  What?  My first thought was valve float, but that had never happened before.  Hitting third gear cleared up the motor and it pulled hard until near time to shift into high.  This time I glanced down as I shifted only to see that as I moved my arm to shift it pulled the sleeve of my leathers out of the front carb into which it had been sucked!  Happy to know that I was not dealing with engine damage but merely rider error, I kept the throttle wide open to the finish line. 

The E.T. suffered greatly from the multiple fiascos on the run (14.12) and the MPH did not fare much better (101.4).  Again the half track MPH is quite revealing.  Apparently having a sleeve in one carb is enough to knock 12 MPH off your speed at the 1/8 mile mark compared to the previous pass.  But you know what?  That turned out to be a good thing.  I had no plans to make another pass due to the temperature.  That would have been just asking for heat stroke.  In fact I remember saying to someone after that second run that it was my last because there was no sense pushing my luck. 

 Remember near the beginning of this post when I mentioned the LORD looking out for us with the trailer tire?  What we found on the Knuckledragger after we returned home made the trailer tire pale in comparison.  The neck on its 1930s era frame is cracked, and not just cracked, but CRACKED!  In fact you can see daylight through the crack it is so cracked.

A little back lighting reveals a major crack.

 

Red arrows point to start and end points.

You often hear, "somebody up there is looking out for me."  Yes, well that is true, but I know who that somebody is and I'm willing to say it.  The LORD God almighty, YHWH is his name.

Parting Them Out

I come to you with a troubling post today. Some may dismiss it as being just too "sentimental" or dismiss me as someone who just needs to lighten up and not take life so seriously. Perhaps many of those who have not spent countless hours on the same old Harley over long periods of time (time measured in decades, not years) will not feel the same. But if you have ever owned, ridden, and lived on/with the same bike for enough time, then you too will likely have formed a bond with it. That bond is often forged while tuning and repairing, repainting and rebuilding the same bike over and over through those many years of ownership; or should we say years of partnership? How often have you heard a fellow enthusiast refer to his motorcycle as his "baby?" Is it any wonder that often the feeling that the machine is more than just the sum of its many mechanical parts is expressed by the bestowal of a name. But even those not predisposed to naming their bikes often wind up feeling that their "old friend" has taken on some type of life of its own, or at least some sort of mystical mechanical soul. I know you guys are out there, because some of you have brought your bike's engine parts to me with the confession that you are VERY careful about to whom they will entrust the internal organs of their pride and joy. Yes, it is plain that many old time bikers would probably, in a moment of sentimentality, wax poetic and confess that there just might be something to the whole idea of old Harleys having a soul.

And that is what makes the subject of this post troubling. I would like to address is what seems to be an increasingly common practice of "parting out" complete and running condition vintage Harleys.

Though it is certain that there have always been back alley operations involved in the dissection of old Harleys, the practice has become more lucrative recently with the popularity of the eBay worldwide marketplace. Given the ever increasing price of vintage Harley parts, I suppose it was bound to happen. It seems that some individuals have found that some old Harleys are worth more in pieces than as a "project" bike, or "basket case" as we used to call them.

This practice of parting out viable Harleys recently came to my attention via the aforementioned eBay. One need not search too deeply under Antique, Vintage, Historic in the Motorcycle Parts category to find one. Often the purveyors will be so blatant as to include an admission in the advertisement to the effect that they are parting out the motorcycle so be sure to check their other auctions for the rest of the parts offered. And we can mourn one more vintage Harley which was once someone's 'baby" that will never again feel the wind of freedom against its headlight. The callousness these butchers display as they calmly admit to their profiteering while offering up the parts to the highest bidder is beyond the pale.

Frankly, I find the practice not just troubling, but a bit disgusting as well. Here is an undercover video that sheds much light on this horrendous practice:



　

Okay, if you took the time to view the video, you have realized that it is not about parting out old Harleys, but about something infinitely more wicked; parting out new babies. If you could read my post leading up to the video and have the slightest feeling of agreement, then how much more should you be totally outraged by the practice of Planned Parenthood in not only murdering babies, but then going the extra mile on the road to hell in profiteering from their now lifeless bodies.


It is true enough that we should be far more outraged by the killing of these precious souls than we are by the ghoulish selling of their body parts, but perhaps we have become too complacent with the evil that has been among us since 1973 when the Supreme Court legalized the murder of these babies. Maybe the new revelations of depravity will temporarily be shocking enough to force this nation to turn back from its wicked course. If you are not a Christian, and you shrug your shoulders at this sale of dead baby parts, then you are heaping coals of fire on your already sin laden head. If you are a Christian but you are too busy to spend a few moments fighting this spiritual wickedness, just how do you plan to explain that before the judgment seat of Christ?  All I ask is that every one of you who are men of conscience take a few minutes to do something, whether it be contacting your elected representative, passing this or similar articles along via social media, sending links to your friends and acquaintances, or praying. We all need to do something to not only denounce, but to stop this barbaric practice of child sacrifice.

Satan Caught on Video

If you don't run in the same circles that I do, then you may have missed this blip on the news.  Indeed, the Devil (or at the very least a high ranking minion) was recently recorded doing, well ...the devil's work, in a hidden camera video.

 

 

Okay, I overstated the case a bit when I called Deborah Nucatola (from the above video) Satan.  I'll stand by the high ranking minion description though.  In a strange turn of events another high ranking minion was also recently caught on video discussing the sale of dead murdered baby parts.

 

 

 

 

 

If you can hold down your lunch long enough to get to the end of this video, you may catch Mary Gatter quipping that she wants a Lamborghini; a clear allusion to the profit she can see in the modern day equivalent of grave robbery.  I have to say, Dr. Frankenstein from the tale by Shelley was a far more sympathetic figure; of course that story does not begin to earn the adjective "horror" when put beside the murderous history of Planned Parenthood.

 

By the way, you may want to go back and watch the beginning of the second video one more time.  Cecile Richards.  If Mary Gatter and Deborah Nucatola only qualify as high ranking minions of Satan, when the question becomes, what about Cecile Richards?  Well, Jesus said this:

 

 Ye are of your father the devil, and the lusts of your father ye will do. He was a murderer from the beginning, and abode not in the truth, because there is no truth in him. When he speaketh a lie, he speaketh of his own: for he is a liar, and the father of it. (John 8:44)

Cecile Richards may not be the devil incarnate, but it is plain whose daughter she is.

BUT, wicked as all of this is, the lesson we might learn from the small amount of outrage generated is how depraved our once great nation has become.  A few people may become upset over the ghoulish sale of dead baby body parts, but have they forgotten the millions of babies murdered in the years since the Supreme Court instituted a constitutional right to commit that murder?  You serious Clark?  What is the greater sin?  The murder or the sale of the corpse?

May God have mercy on us, though we surely deserve none.

 

 



Melting Down in July

But in this case it is a good thing.  On July 17, 18 and 19 Byron Dragway will be the scene of the 6th annual Meltdown Drags.  This event is one that you really need to attend to gain a full appreciation for the concept.  From the grandstands you will think you stepped back in time to a 1966 drag race!

Every year this beautiful dragstrip outside of Byron Illinois (near Rockford) becomes home to a weekend that reminds us why drag racing became such a popular sport during the '50s, '60s and beyond.  What make this particular event such a hit is a combination of things.  For one thing, all the vehicles must be 1966 or older.  Add to that, they need to be period correct as viewed from the stands.  That means no modern wheels or "snorkel" hood scoops.  Another key ingredient might be that the Meltdown Drags Crew has chosen to curb the natural inclination of racers everywhere to go faster and faster (translation: spend more and more money) by making it a "grudge racing" only event.  If you're not familiar with the term "grudge racing" it basically comes down to this: no trophies or even class eliminations -for every pass down the strip each racer is free to pair up with another similar vehicle that will provide for a good race.

This event draws in the neighborhood of 500 competition vehicles which includes everything from front engine dragsters to near stock looking sedans.  And gassers.  Lots and lots of wheel standing gassers.

Of course a 1966 drag race scene would not be complete without motorcycles, and the Meltdown Drags, true to its theme, includes them.  Last year's event included somewhere in the neighborhood of 20 motorcycles in competition.  I suspect that may be near the ratio of cars to bikes that one might have found at a typical mid '60s drag race. 

Rumor has it that this year we can expect to see Glen Kerr with his famous world's first twin engine dragbike, Dubble Trubble.  The boys from the AH Garage will likely be there with vintage Harleys ranging from a Knucklehead to a Shovelhead and pretty much everything in between.  Steve McGregor with his double engine Triumph may be there, not to mention Wayne Skinner and his single engine Triumph dragster as he continues to up the percentage of nitro.  Last I heard, John Endrizzi plans to run his supercharged street Knuckle, and I fully expect Jay from Fear No Evo Racing to show up with his Iron XL gasser.  No doubt there will be other bikes there as well, filling out the program.

As for the Knuckledragger, Lord willing we will put in an appearance with it.  I am finishing up a 4 speed transmission for it (built from mostly used parts) because the 2 speed was not really the hot set up combined with a modern slick without nitro: pretty hard on clutch plates.

July 4th 2015

I have to admit that this 4th of July seems more like a funeral than a birthday celebration.  You know how modern day funerals all seem to want to be called "a celebration of the life of ________" (fill in the blank).  Eventually that may be how many of us look at the 4th of July; as a celebration of the deceased's life. 

Just as when we attend a funeral and look back on the life of a friend, we tend to recall the good they did while holding our tongue about the times they fell short.  If that friend was a God fearing man (in the biblical sense) then there is indeed reason for hope regarding their future state. But what if your friend had spent a good portion of his life professing to love God (despite an ongoing struggle between doing good and doing evil, as we all have) only to totally reject God in his later years; celebrating what the LORD condemns?  Not so much hope left for that friend's future.  ...but that would not completely erase the affection you once had for him.

That sort of sums up how I feel about the 4th of July funeral celebration this year. 

Before our move from a house in the city, we flew Old Glory almost constantly, even going to the trouble of lighting it at night.  On holidays such as the 4th we would add the Gadsden flag or the Culpeper flag below it.  When we moved, I considered installing a flag pole here on our new property, but seeing the handwriting on the wall, I held off.  It seemed that it might only find use in raising those flags from the War of Independence - and of course those flags are in the process of being re-defined as racist, so...

One thing is certain though, if we did have a flagpole, Old Glory would only be ascending half way this 4th of July.  Think of it as paying respect to a fallen hero.

In Memory

 

LORD have Mercy

For more on this topic I heartily recommend these articles from men I respect:
JD Hall
Doug Wilson

God Is Not Mocked

Just a couple things that come to mind regarding the recent decision by the Supreme Court of the United States concerning the newfound institution of gay mirage (no, that's not a misprint).

Be not deceived; God is not mocked: for whatsoever a man soweth, that shall he also reap. Galatians 6:7

Embracing gay mirage is not something for which this nation will be judged; it IS the judgment.

Woe unto them that call evil good, and good evil; that put darkness for light, and light for darkness; that put bitter for sweet, and sweet for bitter!  Isaiah 5:20

Being included in any group of whom the LORD says "Woe unto them" is not a good place to be.

And I saw a great white throne, and him that sat on it, from whose face the earth and the heaven fled away; and there was found no place for them.  And I saw the dead, small and great, stand before God; and the books were opened: and another book was opened, which is the book of life: and the dead were judged out of those things which were written in the books, according to their works.  And the sea gave up the dead which were in it; and death and hell delivered up the dead which were in them: and they were judged every man according to their works. And death and hell were cast into the lake of fire. This is the second death.  And whosoever was not found written in the book of life was cast into the lake of fire.  Revelation 20:11-15

Because in the end, God is not mocked.

Memorial Day 2015

 

On Monday this nation will observe Memorial Day for the 147th time. Originally call Decoration Day, it was officially instituted in 1868 as a day to honor those who died serving their country in the Civil War. After World War I, the event was expanded to honor those who have fallen in battle in all the wars in which this country has been involved. Strictly speaking, Memorial Day is set aside to honor only those who died in war defending our freedoms, which is appropriate given their sacrifice.

So, in case you are wondering if or how I am going to tie the observance of Memorial Day to the Bible and Christianity (which of course I am prone to do), let's consider a passage from II Samuel chapter 23.

These words are recorded after David had taken his rightful place as king over a united Israel.

These be the names of the mighty men whom David had: The Tachmonite that sat in the seat, chief among the captains; the same was Adino the Eznite: he lift up his spear against eight hundred, whom he slew at one time. And after him was Eleazar the son of Dodo the Ahohite, one of the three mighty men with David, when they defied the Philistines that were there gathered together to battle, and the men of Israel were gone away: He arose, and smote the Philistines until his hand was weary, and his hand clave unto the sword: and the LORD wrought a great victory that day; and the people returned after him only to spoil. And after him was Shammah the son of Agee the Hararite. And the Philistines were gathered together into a troop, where was a piece of ground full of lentiles: and the people fled from the Philistines. But he stood in the midst of the ground, and defended it, and slew the Philistines: and the LORD wrought a great victory.

And this is but the first three of David's soldiers who are all mentioned by name here. In the rest of the chapter, David goes on to name another 32 of the mighty men of his army. Thus it would seem that when we honor the fallen soldiers of our own nation, we do have some biblical example for doing so.

Consider this from Matthew Henry's commentary on II Samuel 23:　

Note, Those that in public stations venture themselves, and lay out themselves, to serve the interests of their country, are worthy of double honour, both to be respected by those of their own age and to be remembered by posterity. To excite those that come after to a generous emulation.  To show how much religion contributes to the inspiring of men with true courage. David, both by his psalms and by his offerings for the service of the temple, greatly promoted piety among the grandees of the kingdom (1Chronicles 29:6), and, when they became famous for piety, they became famous for bravery.

Now, one might argue that nothing which Matthew Henry said about the piety of Israel's army applies to the soldiers of our United States because we have a separation of church and state, and so we are not a Christian nation. But I would suggest that the idea that we are not a Christian nation would have been totally foreign to the great majority of those who have died in the service of our county for more than two centuries. It is far more likely that most of them embraced the thought that they were fighting for God and Country.

So this weekend, as we honor those who have died for God and Country, let us remember Jesus words as recorded in John 15:13

Greater love hath no man than this, that a man lay down his life for his friends.

Over the course of our nation's history many have shown this type of love through fighting and dying for their fellow countrymen who they counted as friends. We should honor them for the bravery and the love which they displayed.

Even more important though, is how those words of Jesus apply to himself.

"Greater love hath no man than this, that a man lay down his life for his friends." And the next verse continues, "Ye are my friends, if ye do whatsoever I command you." "  Jesus gave us many commands during his earthly ministry, but they could perhaps best be summed up when he said repent, and believe the gospel. (Mark 1:15)

Jesus did lay down his life to pay the just penalty for our sins so that we might be forgiven and spend eternity with him. Won't you repent and believe this good news?

Vintage Dual Carbs, Part 4

Okay, its high time I finish up this series on vintage dual carbs, or more accurately stated: dual carbs on vintage Harleys. In a previous post, I promised to offer what I see as possibly the best compromise between authenticity, performance and feasibility.

For a Knuckle or a Pan, there are three basic ways to achieve dual carbs. First is the obvious: major modifications to the heads (welding and machining) for one carb with an individual runner on each head. This method is probably the most difficult and/or the most expensive. If you are a good welder, machinist, and have porting experience, then it may just the ticket. If you lack one or more of these talents, well, ...that's where the expensive part comes in. It also suffers from the drawback that, for street use, leg interference is normally a major issue, especially with Linkerts. If using Linkerts or other small bore carbs, this method will also limit maximum air flow.

The second method is to mount two carbs on opposite ends of a common manifold, 'a la the Seely manifold of yesteryear. This is perhaps the simplest method and easiest to build. However, it does suffer from the same leg clearance problems of the first method; again, especially with the relatively long Linkerts carbs. One advantage this method does have over the first is the ability to either keep each intake track separate for true independent runner (IR.) operation, or to use the manifold as a common plenum so that each cylinder can draw from both carbs at once for maximum power potential.

A third option, as I see it, is a custom manifold for two carbs mounted side by side on the pushrod side of the engine. On a Knuckle or a Pan, since the intake spigots are at the far left hand (primary drive) side of the engine, this method has the advantage of providing more room to accommodate carburetor length. This allows the dual carbs to be the least intrusive in respect to legroom. The drawback is that this last method leads to a compromise between the tuning advantage of individual runner and the increased flow capabilities or a plenum manifold which allows each cylinder to draw from both carbs. Keep in mind (as pointed out in part one of this series) that a pure individual runner manifold with carbs on the pushrod side of the engine will necessarily suffer from a "pinched" port cross section. Given the limited amount of real estate between the cylinders/port spigots, I just don't see any good way around this.

That leaves us with one option (in my humble opinion) as the best overall compromise for vintage style dual carbs. That would be a manifold with a runner from each carb, which merges into a common runner before splitting off into each port. A variation of this would be for the carbs to mount on a "plenum" which then feeds into two separate runners which attach to the ports on the heads. In practice, the section of either of these manifolds which attaches to the heads will essentially mimic (if not actually begin life as) a stock "T" manifold (or in the case of Shovelheads "Y" manifold. For the sake of easy identification, let's call the one a "plenum manifold, and the other an X manifold (for a Shovel it would be pretty much X shaped, though for a Pan or Knuck it would look like an X with the top legs folded down).

X Manifold for Knuck

 

 

 

 

 

Plenum Manifold for Shovel

The natural question then becomes, which is better, a plenum type or an "X" manifold. Outside of building one of each, followed by real world testing of each (including dyno testing), I really cannot give a firm answer. Now if any reader out there would care to provide me with a generous research grant along with dyno facilities, I would be glad to find an answer. As you may surmise from the increasingly length of time between blog posts, I have no spare time to donate. However, we can come get some idea of how such manifolds may work out by use of computer simulations.

As engine simulation programs go, there seem to be three levels readily available. There is the very basic type which uses a limited number of inputs. While these can be fun and useful, they definitely have their limitations. The mid-level programs use many more inputs, provide for a higher level of accuracy, and of course cost more. Finally, there is the professional level simulation program with even more inputs and even higher purchase prices. The basic simulators generally can be purchased for $100 or less, the mid level in the $200-$300 range, with the professional versions in the $500 range.

The simulator which I own, Engine Analyzer from Performance Trends, falls into the middle category. To give you an idea of the data that is utilized in this program, here is a partial list: Bore, stroke, rod length, windage, friction losses, compression ratio, combustion chamber shape, valve diameters, flow efficiency, port diameter, port volume, port centerline length, manifold diameter, manifold centerline length, manifold flow efficiency, runner length, carb cfm, ...and that only covers the first three of seven screens of data to be entered. Obviously the more accurate the data entered, the more accurate the results. The real strength in a program such as this is not in the hard numbers it produces, but rather is revealed in the company name itself:  Performance Trends. While the actual horsepower and torque numbers produced by the program may not match real world results exactly, by changing input data one step at a time, one will see a "trend" in the results.

So, ...to the simulator! The logical first step was to enter everything in as accurately as possible to match a stock 74 cubic inch Knucklehead. Well, almost stock. I used the flow figures for an unmodified FHP/S&S Knuckle head along with an Andrews "N" Knucklehead cam. The N cam is what Andrews calls its "stock replacement" and though its specs don't quite match my own measurements for an OEM cam, or the S&S stock replacement Knuck cam, I already had the specs loaded into the program and deemed it suitable for these tests.

As I stated earlier, the actual numbers that the program predicts are of much less consequence than the "trends" that it reveals, though I might mention that the numbers generated looked reasonable, remembering that rear wheel HP recorded on a chassis dyno will be 10-15% lower Here was the first thing of note: changing from the stock Knuckle M35 carb to the slightly larger M74 resulted in a gain in average torque (across the tested band of 1500 to 6000 RPM) of 4-1/2 foot pounds, along with along with gain in average horsepower of 4. Peak torque went up by nearly 7 ft pounds and the horsepower peak went up by 5, but also peaked at 500 RPM higher than with the M35 (5000 RPM vs 4500).

M35 vs M74

Next up was to input the added runner length of the dual carb "X" manifold without the additional flow capability of a second carb. This model shows an increase in both torque and horsepower across the entire RPM range, which suggests that added overall intake tract length for the dual carb manifold is a performance enhancement all by itself.

But we really aren't going to the trouble of building a dual carb "X" manifold just for the length, are we? Inserting the flow from an M74 combined with an M35 results in even more impressive gains. Peak torque is up nearly 9 foot pounds compared to the M74 on a stock manifold, while peak horsepower increases by almost 13. Average torque across the tested RPM range is up by 8 with average horsepower up by 7. Perhaps just as important is that the dual carb model show the torque as higher than the stock carb and manifold at all RPMs, even compared to the single M35. That would suggest that we are not going to give up any lower RPM performance in the search for top end power with the dual carb manifold.

M74 on stock manifold vs dual carbs on X manifold

Perusing all of the data, it appears that the M35 on a stock manifold is limiting the peak torque to 3000 RPM and the peak HP to 4500. The simple change to an M74 raises the torque peak to 3500 and the HP peak to 5000, indicating the restriction of the M35. The addition of the dual carb manifold with two carbs leaves the RPM for peak torque at 3500, but raises peak HP to 5500.

At no point in the torque curve did the M74 produce less than the M35. In fact, subsequent "runs" with even much larger carbs still showed a horsepower peak at 5500 RPM (the peak number increased, but not the RPM at which it was reached). That indicates to me that the M35 was limiting the RPM of peak HP, whereas with an M74 there is some other factor that is limiting it (in fact increasing the cylinder head air flow in the test did result in the RPM for peak HP increasing).

Plenum vs X manifold shows which is clearly the better street choice

 

Of course these tests don't tell us much about throttle response and overall driveability, but that's where a little personal experience weighs in. While I have not had the opportunity to field test an "X" manifold, I do have some personal experience with a "Seely" style manifold with no divider which allows each cylinder to draw from both carbs. When I built such a manifold about 25 years ago, it seemed logical to set it up in much the same way as an automotive 4 barrel carb. If you consider a typical 4 barrel, you will notice a couple things. One is that the "primary" throttle plates are normally smaller than the secondary's. The second is that the linkage provides for the primary throttle plates to open part way before the secondary plates begin to open: this is commonly called progressive linkage.

Now think about what that means for a moment. The smaller primary plates will naturally result in better fuel mileage and throttle response when you don't "have your foot in it." The larger secondary plates will allow maximum air flow for WOT (wide open throttle) situations. That should make for a pretty good all around compromise between driveability, mileage, and power. And such proved to be the case. I fabricated throttle linkage (shown below) which allowed the M35 that I used as the primary carb to reach 1/2 throttle before the M74 secondary carb began to open, but which also caused both carbs to reach wide open at the same time. As an added airflow enhancement, I only ran a choke plate on the primary carb (though the choke shaft remained in place on the M74 to keep the low speed needle adjustment mechanism).

Throttle closed

Right carb at 1/2 throttle, Left about to start opening

Both carbs at full throttle

Starting was as easy as stock, and as I recall required abut the same procedure as with one carb. Throttle response was as good as stock. WOT performance was very good, and in fact when I would "roll on" the throttle, I could feel when the second carb started to open, much like you can feel the secondary's of a 4 barrel carb on your V-8 kick in. (Come on, ...at least some of you had to have ridden in an antiquated car with a 4 barrel carburetor.)

Of course this setup was not on a completely stock Knucklehead, which has the potential for skewing some of the results. The engine remained 74 inches, but it used two right side flywheels allowing quicker revving. It also had ported heads with larger valves, along with a 110 Sifton cam; you know... typical Knuck hop up stuff of days gone by.

Full disclosure; the one glitch that I never did quite work out entirely to my satisfaction (at least from a curiosity standpoint) was the idle speed. With the circuit breaker at full advance the idle speed would remain too high despite my attempts to disable the idle circuit of the secondary carb. I think it was due to my use of typically worn out Linkert carbs (with excess wear to the bodies at the throttle plates) allowing too much air to sneak through. Since I did not have any better carbs to try, I "solved" the problem by installing a late '60s auto advance circuit breaker which I did happen to have in my parts stash.  Problem  not solved, but symptoms masked.  Whether I was correct that the source of the high idle was worn out carbs, or if I simply did not do a good job of disabling the idle circuit remains to be seen, and any input from someone with similar experience is welcomed.

So, there you have it, an "X" shaped dual carb manifold; ...my best compromise solution for dual carbs on a vintage Big Twin. No need to do extensive and expensive modifications to your heads. By avoiding the short runner length of a plenum type manifold, RPMs for toque and horsepower peaks stay at a street friendly level. And perhaps one of the biggest advantages is that it sticks out less than 3 inches further than the stock set up, or about an inch more than an S&S E.

Ignore the linkage shown here - pic was taken early in the mock up process