Wednesday, March 11, 2015

Rumors of my Demise...

Well, I am not aware that there are actually any such rumors circulating yet, though it has been so long since I have posted you may have wondered.  The truth is I have just been so busy trying to keep my head above water in the shop that I have, to my shame, not been able to finish the final installment of Vintage Dual Carbs

One small part of the hold up is that I would like to make part 4 a little more than just a commentary on my past experience, however given the difficulty finding time to write, its unlikely I will find time to do actual real world testing any time soon.  That's where computer simulations come into play.  I would like to take the time to run some simulations on my Engine Analyzer software to re-enforce my thoughts for a good compromise for dual carbs on a vintage Harley.  Nothing takes the place of actual testing, but I fully expect that with some careful measurements and time with the program some valuable information will be revealed.

So stay tuned...

Tuesday, December 23, 2014

One King, One Kingdom

In one of my recent posts, I ventured to state that I had found the answer to a minor point of curiosity on my part dealing with the presence of two similar terms used in the Bible, those terms being "kingdom of heaven" and "kingdom of God". My answer, based on two verses in the Gospel of Matthew was that they are the same.  A reader was quick to point out to me that there is indeed a distinct difference between them in that the kingdom of heaven is a literal physical kingdom that the Jews will inherit while the kingdom of God is a spiritual kingdom that the Church will inherit. In this post I would like to attempt to imitate those of Berea and search the scripture to see if this is so.

As we look at the occurrences of the two terms, it becomes evident that if they are not two names describing the same kingdom, then at the very least both kingdoms share a number of striking similarities.

For instance, from Matthew 13:10-11 and Mark 4:10-11, we can see that truths about both the kingdom of heaven and the kingdom of God were revealed by Jesus in parables so that only those who were chosen to understand, would understand. In fact from these verses we also must conclude that the same parable of the soils can be used to reveal the same mystery regarding each kingdom.

Matthew 13:31-32 coupled with Mark 4:30-32 inform us that both the kingdom of heaven and the kingdom of God are like a grain of mustard seed.

Mark 10:14 and Matthew 19:14 together inform us that both kingdoms are made of those who share the characteristics of little children.

From Matthew 11:11 and Luke 7:28 we may glean that he who is least in the kingdom of heaven is greater than John the baptist, ...and that so is he that is least in the kingdom of God.

Now, the fact that the kingdom of heaven and the kingdom of God share these four characteristics does not by itself prove that they are one in the same, but it should at the very least make one take it into consideration.

If one were to take the position that the kingdom of heaven is to be the inheritance of the Old testament Jews and the kingdom of God will be made up of New Testament saints, then one must consider that Jesus, as recorded in Mark 1:14-15, preached repentance and that the kingdom of God was "at hand." But John the baptist, in Matthew 3:2 preached "repent" for the kingdom of heaven is "at hand." This poses a bit more of a problem for the two kingdom view. It is easy to see a spiritual kingdom as being at hand (or "drawn near", as some translations put it), but how would one apply being "at hand" to a literal physical kingdom for the Jews. If anything concerning such a kingdom was at hand, it was its destruction by Titus in 70 A.D. The absence of anything resembling a Jewish kingdom for nearly 1900 years can hardly be something easily reconciled with "at hand." Was John mistaken or could both he and Jesus have been describing the same kingdom with different words?

Perhaps just as puzzling would be the conversation between Jesus and Niccodemus as recorded in John chapter 3. In verse 3 Jesus says "Except a man be born again, he cannot see the kingdom of God." Okay, if there are two kingdoms, that tells us that the spiritual kingdom occupied by the New Testament believers can only be seen by those who are born again. That is all well and good, but a few verses later Jesus expresses surprise saying "Art thou a master (teacher) of Israel, and knowest not these things?" Well, least I guess you could read that as surprise. I personally don’t believe that Jesus was ever surprised; I see that statement as more of a chastisement. But either way, why should a teacher in Israel be expected to know about a new kingdom that was just coming into existence? Odd.

Another piece of scripture that does not quite seem to fit in with a two kingdom view can be found in Matthew 16:19 where Jesus announces that he will give the keys to the kingdom of heaven to the disciples. Now this verse has often been used (and too often abused) to assert power given to the church. But was Jesus real purpose to teach that the church will have power over the physical kingdom occupied by Old Testament saints?

In my original post on this subject, the scripture that I presented in support of my understanding of the kingdom of heaven and the kingdom of God being one in the same was Matthew 19:23-24. Here is what my argument consisted of: In verse 23 Jesus exclaims how hard it is for a rich man to enter the kingdom of heaven, and then in verse 24 he goes on to say "And again I say unto you, It is easier for a camel to go through the eye of a needle, than for a rich man to enter into the kingdom of God." (Emphasis mine). I postulated that by using the term "again" Jesus made the terms interchangeable, else he would have used the world "also." Of course this argument rests on the reliability of the translation of the Greek word "palin" which it appears could in some cases be translated as "furthermore" instead of "again." However, I am not aware of any translation which uses any word except "again" in this verse. I am pretty sure the translators are smarter than I am and very likely got it right.

The objection I received to my use of this verse to support my case was that one should not build a doctrine on a single verse. I agree completely; thus the study that went into this post. I do have one more argument to offer though, and I believe it to be the strongest one, when taken in conjunction with what I have already presented here. That argument comes from Matthew 8:11 "And I say unto you, That many shall come from the east and west, and shall sit down with Abraham, and Isaac, and Jacob, in the kingdom of heaven." Now consider Luke 13:28 which says: " There shall be weeping and gnashing of teeth, when ye shall see Abraham, and Isaac, and Jacob, and all the prophets, in the kingdom of God, and you yourselves thrust out."

The fact that Abraham, Isaac, and Jacob are said to be in the kingdom of heaven and in the kingdom of God, taken alongside everything else I have presented here, leads me to the inevitable conclusion that those kingdoms are one in the same. One King, One Kingdom.

I am thankful for the "nudging" which I received to search the scriptures for a proper understanding, but I must add that much more than that, I rejoice that I will someday be able to sit down with Abraham, Isaac, and Jacob in the kingdom of heaven.

Thursday, December 18, 2014

Vintage Dual Carbs, Part 3

In part three of this treatise on dual carb Harleys, I would like to put the venerable Linkert under the proverbial microscope. First stop will be an unlikely source for an avowed Knucklehead fanatic such as myself, that being the ’48 to ’57 Panhead Service Manual. The last page of the carburetor section has a handy-dandy chart listing most (all?) of the carbs used from 1936 to 1957. Along with applications, throttle disc angles and even transfer port dimensions, we find venturi sizes listed. Hats off to those technical writers of yesteryear; if only their modern day counterpart would follow their lead.

For our purposes here though, the venturi sizes are indeed what is most useful. The first one we might note is the 3 bolt M-5/ M-55 of early 61" Knucklehead fame. They featured a venturi bore of 1-1/16". OK, so what, you might say. Well, let me put that in terms of modern carbs: 27mm (rounded off). That friends, is not a lot of area to get much air through. But as we go down the list, the venturi sizes do increase, but not much. While we do find the M-25/ M-75 with its whopping 1-5/16 venturi on 1940 Knuckles and as an option on ‘41-’48 models, most Knuckles left the factory with the 1-1/8" M-35. Finally, with the 74" Panheads a 1-5/16" venturi became the standard bearer for brass bodied Linkerts on Harleys, being the largest Linkert offered. Again let’s put those sizes into terminology which will make it easier to compare with modern carbs. The 1-1/8" venturi M-35 series carbs were only 28.6mm (again, rounded off). The big kid on the block M-74 comes in at a whopping 33.3mm (do I really need to point out that this figure too is rounded off?). As a point of reference, when Harley switched to Bendix carbs in the mid 1970s, they put a 36mm version on the XL models, which just happen to come in at very near the same cubic inch displacement as the 61" Knuckle, and a 38mm on 74" Shovelheads.

Super E on left, M35 Linkert on right

As a further point of reference, let’s mention a couple modern performance carbs. S and S (why does it bother me so much that blogger’s html will not allow the use of the ampersand?) designates their carbs by the diameter at the manifold surface rather than the venturi size. An S and S Super "E" carb which is called 1-7/8" is actually 40mm at the venturi, while the "G" model’s 2-1/8" bore is 44.7mm at the venturi. Right in between these two carbs is the flat slide Mikuni HSR42. Keep in mind though, none of these three performance carbs relies on a choke plate as a starting aid. All of the Linkert carbs employ such a plate, which further limits their air flow beyond what the already smaller venturi does. And the measured airflow through these carbs bears this out. An S and S "E" carb flows a whopping 73% more than an M74 despite the venturi bore being only 20% larger.

Knuckledragger Carbs
Right about now you may be thinking, "What about all those old pictures I’ve seen of vintage drag bikes with a pair of Linkerts fitted?" In fact, those paying close attention may even wonder why my own vintage drag bike, "The Knuckledragger" breathes through a pair of them. Speaking for my own situation, I had two reasons to use Linkerts. Nostalgia and pragmatism. The nostalgia portion is self evident. The pragmatic stems from the simple reason that the heads I had in my possession for the project were already set up with Linkert 4 bolt flanges. Had it been a more serious performance effort, I would have reworked the heads.  As it is, I still cut the choke assemblies off, added radius inlets and swapped to the somewhat larger 1-5/16" venturi's on the M35 carbs to maximize air flow.

Granddaddy Joe Smith still ran Linkerts on his Knuckle just before switching to a Shovelhead
The reason you see Linkert in old pictures of early drag bikes is also pretty straight forward, though maybe not so self evident. Many of the drag bikes you see outfitted with a pair of Linkert carbs were run on nitro methane fuel . "Nitro" as it is commonly called among racers, is quite different than gasoline in that it has oxygen in its chemical makeup. That means that rather than relying on airflow to get enough oxygen into the combustion chamber, with nitro a goodly portion of that oxygen is supplied by way of fuel flow. Remember back in part 3 when I wrote this? "The problem is very seldom getting enough gas into the engine for high performance, the challenge is in getting enough air in." Perhaps I should have more specifically used the word oxygen rather than air and fuel rather than gas, but I think you get the picture.

 That is not to say that the addition of nitro turns the Linkert into killer performance carb with no other changes. Nitro requires a much, much, much richer fuel to air ratio. For a given amount of airflow, nitro will need about 7-1/2 times as much fuel as the same engine running gasoline. This requires some substantial modifications to the fuel delivery system all the way from the petcock to the float system to the jets. The potential results however, are nothing short of awe inspiring. A switch from gasoline to nitro methane comes with a potential of just over double the horsepower. Do I need to mention that the bike and the rest of the motor needs to be strong enough to survive double the power?

Now it looks like this series will drag out into yet another post. God willing, I plan to wrap it up in a post encompassing my thoughts on what makes a viable street application for vintage style dual carbs.

Tuesday, November 25, 2014

Thanksgiving: What, When and How

this is the second half of the post started here...
We should give thanks for other Christians and churches.  1Thessalonians 1:2   We give thanks to God always for you all, making mention of you in our prayers;

We should thank the LORD for deliverance from the world.  1Chronicles 16:35  And say ye, Save us, O God of our salvation, and gather us together, and deliver us from the heathen, that we may give thanks to thy holy name, and glory in thy praise.

We should give thanks for salvation and sanctification.  2Thessalonians 2:13  But we are bound to give thanks alway to God for you, brethren beloved of the Lord, because God hath from the beginning chosen you to salvation through sanctification of the Spirit and belief of the truth:

We should give thanks to the LORD that he has made us fit to share in the inheritance of the saints.  Colossians 1:12    Giving thanks unto the Father, which hath made us meet to be partakers of the inheritance of the saints in light:  

We should give thanks to the LORD when it is not convenient.  Psalm 119:62   At midnight I will rise to give thanks unto thee because of thy righteous judgments.

We should give thanks to God when we pray.  Philippians 4:6   Be careful for nothing; but in every thing by prayer and supplication with thanksgiving let your requests be made known unto God.

We should give thanks to God continually.  Hebrews 13:15  By him therefore let us offer the sacrifice of praise to God continually, that is, the fruit of our lips giving thanks to his name.

We should give thanks the God at all times.  Ephesians 5:20   Giving thanks always for all things unto God and the Father in the name of our Lord Jesus Christ;

We should give thanks to the LORD into eternity.  Psalm 30:12   To the end that my glory may sing praise to thee, and not be silent. O LORD my God, I will give thanks unto thee for ever.

We should give thanks to God when we come together with other Christians to worship.  Psalm 35:18   I will give thee thanks in the great congregation: I will praise thee among much people.

We should give thanks to the LORD when we are among non-Christians.  2Samuel 22:50 & echoed in Psalm 18:49   Therefore I will give thanks unto thee, O LORD, among the heathen, and I will sing praises unto thy name.

We should give thanks to God when we are with the younger generation.  Psalm 79:13   So we thy people and sheep of thy pasture will give thee thanks for ever: we will shew forth thy praise to all generations. 
We should give thanks to the LORD by singing songs dedicated to him. Psalm 95:2   Let us come before his presence with thanksgiving, and make a joyful noise unto him with psalms.

We should give thanks to God by praising him and blessing his name.  Psalm 100:4   Enter into his gates with thanksgiving, and into his courts with praise: be thankful unto him, and bless his name.

We should give thanks to God by joyfully declaring what he has done.  Psalm 107:22   And let them sacrifice the sacrifices of thanksgiving, and declare his works with rejoicing.

We should give thanks to the God by calling on his name.   Psalm 116:17   I will offer to thee the sacrifice of thanksgiving, and will call upon the name of the LORD.

We should give thanks to the LORD by doing everything in his name.  Colossians 3:17  And whatsoever ye do in word or deed, do all in the name of the Lord Jesus, giving thanks to God and the Father by him. 

These are just some of the thing that scripture tells us about the thanks giving.  If I were to summarize, I would say that the biggest reasons why we should give thanks to God are who he is and what he has done.  The when and where are that we should give thanks to God wherever we are and constantly.  How we should give thanks to our Lord is by praising his name and living for him.  And what we should give thanks for are all things, but especially for salvation.  God provided a means by which sinners like you and me could be saved from both the bondage of sin and the penalty of our sin.
That salvation is found in the sinless life of the Son of God, Jesus Christ, who paid the price for all of our sins, past present and future, on the cross at Calvary.  He suffered and died in our place, then rose again from the dead on the third day, that we might be declared righteous before God and live a life of thanksgiving to him.

Thursday, November 20, 2014

Thanksgiving: Why?

One week from today is the day which our nation sets aside every year as a day of Thanksgiving.  For the Christian, this is a day set aside to give thanks to our great God and Savior, the creator and sustainer of heaven and earth.

The Bible has a lot to say about giving thanks.  I have selected a number of verses and grouped them into five categories.  Those categories are: Why we should give thanks, What we should give thanks for, When we should give thanks, Where we should give thanks, and How we should give thanks.  Today I would like to look at the WHY.

We should give thanks to God because of who he is.  First of all we should give thanks to him because he is holy.  Psalm 30:4 Sing unto the LORD, O ye saints of his, and give thanks at the remembrance of his holiness

We should give thanks to the LORD because he is sovereign over all things.  Revelation  11:17  Saying, We give thee thanks, O Lord God Almighty, which art, and wast, and art to come; because thou hast taken to thee thy great power, and hast reigned.

We should give thanks to the LORD because it is a good thing to do and because he is the most High God.  Psalm 92:1   It is a good thing to give thanks unto the LORD, and to sing praises unto thy name, O most High:

We should give thanks to God because he is good and because of his great mercy.   Psalms 106, 107, 118, and 136 all begin with these same words which we also find in 1 Chronicles 16:34.  1Chronicles 16:34   O give thanks unto the LORD; for he is good; for his mercy endureth for ever

We should give thanks because the great things he has done have revealed him to us. Psalm 75:1   Unto thee, O God, do we give thanks, unto thee do we give thanks: for that thy name is near thy wondrous works declare.

We should also give thanks to the LORD because his judgment is always right and just.  Psalm 119:62   At midnight I will rise to give thanks unto thee because of thy righteous judgments.

And not only should we give thanks because of Gods righteousness, we should give thanks because through his marvelous gift of salvation we may also be called righteous and be counted among them spoken of here in Psalm 140:13  Surely the righteous shall give thanks unto thy name: the upright shall dwell in thy presence.

We should give thanks to God because he is the one who provides salvation.  Jonah 2:9   But I will sacrifice unto thee with the voice of thanksgiving; I will pay that that I have vowed. Salvation is of the LORD.

We should give thanks to God because it leads to our being able to live in peace.  1Timothy 2: 1-2   I exhort therefore, that, first of all, supplications, prayers, intercessions, and giving of thanks, be made for all men;   For kings, and for all that are in authority; that we may lead a quiet and peaceable life in all godliness and honesty.

We should give thanks to God because it is his will that we do so.  1Thessalonians 5:18   In every thing give thanks: for this is the will of God in Christ Jesus concerning you.

We should give thanks to God because it magnifies him.  Psalm 69:30   I will praise the name of God with a song, and will magnify him with thanksgiving.

We should give thanks to LORD because it brings glory to him.  2Corinthians 4:15   For all things are for your sakes, that the abundant grace might through the thanksgiving of many redound to the glory of God.

Wednesday, November 12, 2014

...a brief intermission...

This will be short.  No sooner did I mention that I did not recall ever seeing a pair of SU carbs used on a dual carb Knuckle than I received the pictures below from Glenn in Australia.  It seems that his friend Billy campaigns a Knuck with just such a setup.

The 79" Knuckle motor is reported to put 96 HP to the rear wheel on methanol.  Everything else about it is a secret.

What is there to say but WOW!

Friday, October 31, 2014

Vintage Dual Carbs, Part 2

Airflow.  That's what its all about, at least for the performance enthusiast.  More air (carrying the proper mix of fuel of course) = more power.  Even what is often the first modification, open exhaust, falls into this category as evidenced by the fact that a less restrictive exhaust will require richer jetting to go along with the increase in air intake.  Obviously the same goes for the air cleaner.  So what's next after that? 

Bigger carbs, bigger valves, and porting are all the radar screen for those in search of horsepower, and that's not a new development. If I am not mistaken both Chet Herbert in the late '40s and George Smith Sr. in the '50s ran Riley carbs on their famous dual carb Knuckle drag bikes.  The Riley carbs were originally a racing part for Model A Ford engines.  I can only speculate at this late date that the reason for their existence was for increased air flow. 

 So perhaps this is the appropriate point to mention a few fallacies.  One is that when running one carb one each head (aka individual runner), you need to use smaller carbs than when using one carb to supply both heads.  Think about this for a moment.  On a V twin engine, both intake valves are NOT open at the same time.  Ignoring for a moment any tuned length/ram effect, that means a carb that is too small to be a performance carb with a conventional intake manifold will also be too small to be a performance carb when used on a one carb per cylinder set up.  As a matter of fact it seems that the experts, i.e. anyone I regard as smarter than me (a long list to be sure), suggest that on a individual runner set up, the carb actually needs to be larger than for conventional set up due to the lack of a "plenum effect".  If I follow the reasoning correctly, it is because a plenum will actually help to dampen the large fluctuations in pressure in the intake tract from the valve opening and closing.  This effect would be smaller on a two cylinder than 4, 6 and 8 cylinder engines, but present none the less.

On the other extreme I have had someone with a dual carb set of heads, upon hearing my opinion that the carbs were too small, state that, "Yeah, but hopefully I can jet them up enough to work."  Well, sure you can jet them "up" to work.  All that takes is the right jet to maintain the correct fuel/air ratio.  The problem is very seldom getting enough gas into the engine for  high performance, the challenge is in getting enough air in.  That's what makes a carb too small for a performance application; lack of air flow, not lack of fuel flow.  But more on that later.

So, what was the hot set up for dual carbs "back in the day?"  Well, I suppose that would depend a lot on your exact definition of "back in the day."  Forty years ago (back in the mid '70s) a large round slide Mikuni was a common performance upgrade to replace the aging Linkert, as were SU carbs adapted from British automobile applications.  The Mikuni was a natural for dual carbs, though the popularity of said dual carb builds was on the wane primarily due to the more flow friendly intake tract of Shovelheads and Sportsters. I can't say I remember ever seeing a dual carb Harley with SU carbs, though the constant velocity design would seem to be nearly ideal for the job.

Going back a little further in time, it seems that Italian made Dellorto carbs may have been one of the most popular for use on dual carb heads.  Their SSI series slide type carbs were available in sizes up to 42mm making them a good choice.

highly modified Knuckle from the mid '60s sporting Dellorto carbs

Ron's vintage Knuck also features early Dellortos - more on this bike here

"Famous" Doug Gall used a pair of later Dellorto carbs

Now, cool as the Riley and Dellorto carbs may be, due to their scarcity one will probably not find many of them being used on modern "period correct" builds.  What you will generally find is Linkerts.  Yes, they seem to be constantly rising in cost, but compared to a Riley carb they are still dirt cheap. 

pair of modified Linkerts on The Knuckledragger

So, how does the Linkert stack up as a performance carb, you ask?  We'll look into that in part 3.