Sunday, December 30, 2012
"We spent Sat and much of Sunday preparing The Goose for tech. After passing tech Sunday afternoon we had a freak thunderstorm, which left 2 inches of standing water on the Salt. Racing resumed Tuesday morning! We made our first pass that day after waiting in the starting queue for over 4 hours. By the time Terry set off from the starting line a very brisk crosswind had come up. He found the bike being blown from one side of the course almost hitting a marker flag on the opposite side. This was in the measured mile. He backed off the throttle. Later, he said that he was at 1/2 throttle and accelerating when the gust of wind hit him. The result was 115.929 mph. This was enough to break the Sid Biberman Vincent’s standing record of 109.079. By the time that we got the bike back to the pit, the wind speed had not died at all. It was decided not to make the return pass, which would be needed to post a new record. The next morning it was another long wait for our turn to run. Terry got off the line in good fashion and the bike sounded good thru 1-3rd gears. At the top of third, a little change in the motors rhythm was heard. While on the way down the return road, we heard the announcer say that our bike had run 59 MPH! Once back at the pit we found the rear cylinder had a holed piston. That was end of racing for The Goose!"
And, indeed that was the end of racing for the Grey Goose ...for 2012. The motor is back in my shop, apart and waiting for new pistons. If you read the previous posts on this engine build, then right about now you are no doubt saying to yourself, "So, welding the pistons turned out to be a bad idea after all!" Or maybe even, "What kind of moron would weld on pistons anyway?"
I must admit, those were my first two reactions also. After discussions with various sources ranging from fuel manufacturers to legendary engine builders, it seems not to be so cut and dried. (And a big thank you to John for taking the initiative to seek out those conversations!).
First off, a few clues. The front piston survived its excursion to the Salt Flats with absolutely no sign of any problem. The team had not yet even started to lean out the jetting from its Minnesota baseline. That in itself makes the possibility of a lean condition being the culprit very improbable. The rear piston not only had a hole through the flat of the intake valve relief, it had also started to "sag" on the flat of the exhaust valve relief. Drilling a small hole through the center of the "sag" allowed me to get an accurate measurement of the thickness at that point. It was approximately .200" thick, which was just about the figure I was shooting for when I modified them. The "sag" along with the appearance of the hole itself lead me to think that it was a heat problem rather than a detonation problem.
But all of that really left me none the wiser as to what had actually gone wrong. Obviously new pistons that would not require the drastic modifications I performed on the last set were in order. And I may have left it there, trusting that the hole in the piston was due to my overzealous welding in pursuit of compression, but for one dissenting opinion. One of the experts who John contacted in search of answers was Minnesota's own Mike Roland. Mike did not think that the welding was to blame. In fact, were it not for the fact that I personally believe that Mike is one of the brightest people to ever get involved in the Harley performance arena, I would have dismissed his idea without giving it any thought. But when Mike speaks, I tend to listen; and closely at that!
When John contacted Mike for his thoughts, he immediately asked if it was the rear piston, and if it was a dual fire ignition. Yes, and yes. Well, it seems that at Bonneville, it is very common for Harley's to hole (using "hole" as a verb) the rear piston when using a stock style dual fire ignition. I did not know that. The team members for the Grey Goose did not know that. Judging from other Bonneville stories I have since heard which feature "holed pistons", many others did not know that.
John's conversation with Mike Roland suggested a cure for the holed piston phenomenon (single fire), and even a reason for it (dual fire), but not an explanation. That is not to say Mike did not have an explanation ready; just that John did not ask for one. This left me with several options. I could dismiss the dual fire scenario as the cause of the hole in the piston ...but I have too much respect for Mike's reasoning skills to make that mistake. I could just go with Mike's advice and tell the team they need to switch ignitions. That would be the simplest solution, but hardly gratifying intellectually. I could give Mike a call and ask for his explanation. That would certainly be the quickest, but where is the satisfaction in that? Sort of like turning the page over to get the answers to a crossword puzzle rather than fully exercising you brain to get them. That bring us to the last option, and the one I ultimately went with: I could sit down and spend the time to figure out why a dual fire ignition could cause the problem.
My conclusions will be the subject of another post in the very near future, Lord willing. In the mean time, readers are encouraged to submit their ideas in the comments section. I already have my own explanation worked out and I promise not to borrow from anyone else without giving proper credit.
Wednesday, December 19, 2012
Now, I no more expect that the world is going to end on December 21, 2012 than I believed in Camping's nonsense (or Al Gore's nonsense for that matter) and the date may have slipped by without notice had it not been for my lovely wife. You see, my better half works in an office that attracts far more than its share of new age wackos. One of them recently asked her if she was frightened by the prospect of the upcoming world's end. Talk about a wide open witnessing opportunity! ....but my wife is an employee, so stealing her boss's time, even for a such noble purpose, is just not in the cards. But that doesn't mean I can't get in on the action, so here goes.
Are you frightened about the end of the world?
Actually not such a bad question. The Bible tells us this in the book of Hebrews: And as it is appointed unto men once to die, but after this the judgment: That ought to cause all but the most hardened to pause for thought. Suppose the world did end this Friday. What then? Well, the implication of the "world ending" is that we would all die. But the truth of the matter is this: its much more likely that YOU will die this Friday. No, I don't have some inside information about you personally, in fact chances are very good I have never met you. But look at the statistics on death. A whole lot of people die every day. Do you think you will never be one of those statistics?
While you contemplate your own mortality, though, don't forget the second part of that verse from Hebrews: but after this the judgment. So just when you have started to come to terms with the fact that you could die at any time, I go and throw the concept of judgment into the mix. Fine ...you can pretend that there is no God, and/or that there is no judgment ...that the Bible is not the Word of God, or it has mistakes, or whatever other little dodge you use to soothe your conscience ...doesn't change a thing!
The answer of course can be found in the line after the one quoted above: So Christ was once offered to bear the sins of many; and unto them that look for him shall he appear the second time without sin unto salvation.
There is only one thing that save you from things going very badly in that judgment, whether said judgment happens years from now, on Friday when the Mayan Calender expires, or later tonight. That is the blood of Jesus Christ. Unless you have already put your trust in the Lord Jesus and his sacrifice for your sins, there really needs to be a sense of urgency, end of the world or not.
Wednesday, December 5, 2012
The Old Testament book of Kings tells the tale of the vicious cycle of God's chosen people backsliding, and eventually repenting, only to backslide again. Through all of those cycles, more often than not, the national tone was set by the King who was in power at the time. Both Judah and Israel had kings who followed the LORD, and those who did not, at various times in their history, though it seems that Israel always had more than their share of wicked kings. When you consider the wicked kings, most would agree that Ahab was the worst of the worst. His bad reputation is perhaps only exceeded by that of his wife Jezebel.
That is the backdrop for 1 Kings 18. Ahab and his wife Jezebel reigned over the nation of Israel. They had caused the people to worship a false god named Baal, and had even broken down the alters of the one true God.
And it came to pass, when Ahab saw Elijah, that Ahab said unto him, Art thou he that troubleth Israel? And he answered, I have not troubled Israel; but thou, and thy father's house, in that ye have forsaken the commandments of the LORD, and thou hast followed Baalim.
Now therefore send, and gather to me all Israel unto mount Carmel, and the prophets of Baal four hundred and fifty, and the prophets of the groves four hundred, which eat at Jezebel's table. So Ahab sent unto all the children of Israel, and gathered the prophets together unto mount Carmel. 1 Kings 18:17-20
Here we have the Biblical version of the showdown at the OK corral, or as my title suggests, showdown at mount Carmel.
And Elijah came unto all the people, and said, How long halt ye between two opinions? if the LORD be God, follow him: but if Baal, then follow him. And the people answered him not a word. 1 Kings 18:21
Why do you suppose that the people did not answer him? The answer is right here in the verse. They didn't answer because their opinion was divided. On one hand they were the children of Israel, God's chosen people, and they remembered that. But they also had been led away into idolatry, mixing worship of the God of Abraham with worship of the gods of other nations; in this case the Phoenician deity Baal.
Then said Elijah unto the people, I, even I only, remain a prophet of the LORD; but Baal's prophets are four hundred and fifty men. Let them therefore give us two bullocks; and let them choose one bullock for themselves, and cut it in pieces, and lay it on wood, and put no fire under: and I will dress the other bullock, and lay it on wood, and put no fire under: And call ye on the name of your gods, and I will call on the name of the LORD: and the God that answereth by fire, let him be God. And all the people answered and said, It is well spoken. And Elijah said unto the prophets of Baal, Choose you one bullock for yourselves, and dress it first; for ye are many; and call on the name of your gods, but put no fire under. And they took the bullock which was given them, and they dressed it, and called on the name of Baal from morning even until noon, saying, O Baal, hear us. But there was no voice, nor any that answered. And they leaped upon the altar which was made. And it came to pass at noon, that Elijah mocked them, and said, Cry aloud: for he is a god; either he is talking, or he is pursuing, or he is in a journey, or peradventure he sleepeth, and must be awaked. 1Kings 18:22-27
Now, who says a Christian should never use sarcasm? Should never mock false gods? It seems that Elijah thought it was proper!
And they cried aloud, and cut themselves after their manner with knives and lancets, till the blood gushed out upon them. And it came to pass, when midday was past, and they prophesied until the time of the offering of the evening sacrifice, that there was neither voice, nor any to answer, nor any that regarded. And Elijah said unto all the people, Come near unto me. And all the people came near unto him. And he repaired the altar of the LORD that was broken down. And Elijah took twelve stones, according to the number of the tribes of the sons of Jacob, unto whom the word of the LORD came, saying, Israel shall be thy name: And with the stones he built an altar in the name of the LORD: and he made a trench about the altar, as great as would contain two measures of seed. And he put the wood in order, and cut the bullock in pieces, and laid him on the wood, and said, Fill four barrels with water, and pour it on the burnt sacrifice, and on the wood. 1 Kings 18:28-33
Elijah did not want there to be any doubt about what was about to happen. No one would be able explain it away as some natural phenomenon. This was to be unmistakably the hand of God at work. We just saw Elijah command them to pour 4 barrels of water onto the wood, next verse he says this:
And he said, Do it the second time. And they did it the second time. And he said, Do it the third time. And they did it the third time. And the water ran round about the altar; and he filled the trench also with water. 1 Kings 18: 34-35
At this point one might be tempted to think Elijah is just showing off, but certainly there is more to it than that. We already heard that Elijah took 12 stones to build this alter, which represented the 12 tribes of Israel, who were chosen by God to be his people. Here we see that three times, four barrels of water were poured over the sacrifice - in other words a total of 12 barrels. Now if those 12 stones represented Israel and the worship they should have given God, then I think the 12 barrels of water may just represent Israel's resistance to that worship.
And it came to pass at the time of the offering of the evening sacrifice, that Elijah the prophet came near, and said, LORD God of Abraham, Isaac, and of Israel, let it be known this day that thou art God in Israel, and that I am thy servant, and that I have done all these things at thy word. Hear me, O LORD, hear me, that this people may know that thou art the LORD God, and that thou hast turned their heart back again. Then the fire of the LORD fell, and consumed the burnt sacrifice, and the wood, and the stones, and the dust, and licked up the water that was in the trench. And when all the people saw it, they fell on their faces: and they said, The LORD, he is the God; the LORD, he is the God. 1 Kings 18: 36-39
Just a couple of observations and applications. The LORD our God is a jealous God who is worthy of worship. When we elevate some one or some thing to a place of more importance, or even equal importance to God, we are guilty of idolatry just as the nation of Israel was here in our story.
There is judgment coming. Just before Elijah called down the fire God, he prayed that Israel's heart would be turned back to the LORD. But the prophets of Baal were given no such option. You see, the people were guilty of backsliding and involved in idolatry, but they were still God's people. In the following verse, which tells of how the Prophets of Baal fared after the sacrifice was burnt, we see this:
And Elijah said unto them, Take the prophets of Baal; let not one of them escape. And they took them: and Elijah brought them down to the brook Kishon, and slew them there. 1 Kings 18: 40
The prophets of Baal were not just Israelites who had veered off course and mixed idol worship in with worship of the one true God, they completely rejected the LORD. They were enemies of God.
The big question is, which side are you on? Now, unless you are a prophet of Baal, or have otherwise set your heart solidly in opposition to God never to be changed, then it is not too late. If you will turn from your sin and trust in the Lord Jesus as your Saviour, believing that he paid for your sins on the cross and arose from the dead, then you too will become one of God's people. The miracle that the LORD will work in your heart will be just as dramatic as when Elijah called fire down from heaven!
Saturday, November 24, 2012
Introduced in 1953 to replace the ill fated Panhead "hydraulic in the top of the pushrod", certainly the 17920-53A was an big improvement since in 30+ years of wrenching I have yet to see its predecessor in working condition. I did actually meet a man once who claimed that he had a working set in his motor, but I could not verify that he was not either deaf or a liar. But I digress...
So, what is the first thing to do when you find yourself with noisy hydraulic lifters? Adjust them of course. And if that doesn't work, you adjust them again ....and yet again. After one finally realizes that further adjustment is little more than wishful thinking bordering on the vain repetition of the prayers of the heathen, then what?
Now, we have all seen Shovelhead hydraulic lifters that function flawlessly; quiet and trouble free. Common sense would tell us that for the most part this would be the norm, after all, the factory used them for over 30 years. Somehow, though, it is the ones that are noisy that stick in our memory. To be fair, a number of those that seem to be problematic are not to blame themselves, but take on the role of scape goat for other engine parts.
Low oil pressure is the first logical root cause to examine before condemning the hydraulic unit. Most who have been around Shovelheads for any time know to keep an eye on the tappet screen, since all the oil to the lifters must pass through it (hence its name). Debris plugging this small screen can definitely make for some noisy hydraulics, though the type of debris and the amount of time it took to accumulate may also indicate larger problems. Remember, the tappet screen is downstream from the gauge or sender, so you could have a good oil pressure reading, but still not enough pressure at the lifter.
The oil pump itself could also be the culprit, but there again, excess wear could itself be a symptom of worn out parts serving up a metallic oil soup. And then there are the bushings.... Oil pressure will seek the easiest path to relieve itself. Fortunately there are only a few bushings in a Shovelhead motor that are subject to pressure, those being the pinion bushing and the rocker bushings. Now lifter noise in later Shovels with the multi stage oil pumps should not be affected much by loose clearance between the pinion shaft and bushing, since the pump is designed such that it must build pressure against the top end (hydraulic lifters and rocker arms) before the pressure relief valve opens enough to supply oil to the bottom end via the pinion bushing. However, badly worn rocker bushings could still bleed off enough pressure to effectively disable the hydraulic lifters.
But what if you have good oil pressure, the rest of your engine is in good shape, and you still have noisy hydraulics? Well, maybe it's time to revisit that adjustment one last time.
First of all, I prefer to bring the engine to TDC on the compression stroke for one cylinder, and adjust both lifters for that cylinder at that point. I'll assume you can find that place in your engine's rotation. At that point the '59 to '69 FL/FLH-1200 Service Manual tells us to loosen (shorten) the pushrod until we have noticeable shake, and then extend it again until the shake is just taken up (just before it starts to compress the hydraulic unit). From that point we are to extend the pushrod 4 full turns. Fine. I have use that adjustment many, many times with good results.
Now lets look at the '70 to Early '78 FL/FLH/FX/FXE/FXS-1200 Manual. Here we find two methods. One, called the "wet" method is identical to the one we just described from the '59-'69 Manual. The other, called the "dry" method involves removing the hydraulics from the lifter, pulling the two halves apart, and cleaning out the oil (best accomplished with some spray brake parts cleaner or the equivalent). With the hydraulics cleaned of oil, we are instructed to extend the pushrod past the point where the shake is removed and all the way until the hydraulic unit is bottomed out. At this point, extending the pushrod length any further would begin to lift the valve. Here we are instructed to shorten the pushrod by exactly 1-3/4 turns. Again, I have used that adjustment many, many times with good results.
On to the '78-1/2 to '84 1200/1340cc 4 Speed Manual. Here we find the old tried and true "wet" method to be missing in action. And if that is not enough, the dry method has changed just enough to be barely noticeable (I just noticed it this summer after 30 years of valve adjustments). Now we are to follow the same procedure as the "dry" method from the '70-'78 Manual, but instead of 1-3/4 turns up from the hydraulic being bottomed out, now it calls out 1-1/2 turns. Hmm. Do I need to say it? Certainly I have used this adjustment many, many times (depending on which manual I grabbed) with good results.
But here is the interesting thing: for years I assumed that 4 turns down on a wet lifter would result in the exact same adjustment as 1-1/2 (or 1-3/4) turns up on a dry lifter. It does not! In fact, if it were not the for the 1-1/2 vs 1-3/4 discrepancy, I may have never realized this. As it turns out, it takes about 8 full turns to collapse a Shovel hydraulic from its "wet" starting point to its "dry" starting point. That means that using the "wet' adjustment method results in a hydraulic that is 4 turns up from bottomed out rather than the 1-1/2 or 1-3/4 turn up from the dry method.
Obviously the wet method is much less time consuming if you have no other reason to completely remove the hydraulic units from the engine, but it looks as though extending the pushrods 8-1/4 to 8-1/2 might be in order (assuming the factory had good reason to go to a tighter adjustment in later years). But it also becomes obvious that precise adjustment is not critical if all else is as it should be. So next time you adjust your lifters don't sweat it if your wrench slips and you think you may have gotten a half turn off. If its still noisy, better to spend your time investigating whether it is an engine problem or just bad lifters.
Monday, November 5, 2012
For those who pay attention to such things, we are in the midst of the political season, if indeed that season can be said to have a beginning or end anymore. Nevertheless, it cannot help but to wear on the mind, and as often as not, leave one in despair over the future of our nation. The rhetoric only promises to increase in volume and pitch until at least November.
That is why I found myself somewhat chastised, yet at the same time encouraged, by my discovery of a letter written somewhere between 130 and 200 A.D. by one identifying himself as Mathetes to a person named Diognetus. Of course I did not stumble on it as though it were a root across my path as I explored the jungle that is the Internet, but rather I found it quoted on one of my regular stops which is a Christian blog that goes by the clever name of Pyromaniacs.
It has often been my thought that if one could go back to the very early Christian Church, it would be possible to see the right way to live. That those who were taught directly by the Apostles, or perhaps only a generation or two removed from them, would have had to have gotten everything right. Of course, in truth, that is to a large extent a fallacy. Even as the Apostles were still penning the letters of the New Testament, false prophets were making their way into the Church. (2 Cor. 11:13) Still, those early followers of Christ can certainly, by their example, point us toward scripture that we should remember to take heed of.
The following is a small section of the letter from Mathetes. You can find the rest of it here. I used the translation by J. B. Lightfoot.
"For Christians are not distinguished from the rest of mankind either in locality or in speech or in customs. For they dwell not somewhere in cities of their own, neither do they use some different language, nor practise an extraordinary kind of life. Nor again do they possess any invention discovered by any intelligence or study of ingenious men, nor are they masters of any human dogma as some are. But while they dwell in cities of Greeks and barbarians as the lot of each is cast, and follow the native customs in dress and food and the other arrangements of life, yet the constitution of their own citizenship, which they set forth, is marvellous,and confessedly contradicts expectation. They dwell in their own countries, but only as sojourners; they bear their share in all things as citizens, and they endure all hardships as strangers. Every foreign country is a fatherland to them, and every fatherland is foreign. They marry like all other men and they beget children; but they do not cast away their offspring. They have their meals in common, but not their wives. They find themselves in the flesh, and yet they live not after the flesh. Their existence is on earth, but their citizenship is in heaven. They obey the established laws, and they surpass the laws in their own lives. They love all men, and they are persecuted by all. They are ignored, and yet they are condemned. They are put to death, and yet they are endued with life. They are in beggary, and yet they make many rich. They are in want of all things, and yet they abound in all things. They are dishonoured, and yet they are glorified in their dishonour. They are evil spoken of, and yet they are vindicated. They are reviled, and they bless; they are insulted, and they respect. Doing good they are punished as evil-doers; being punished they rejoice, as if they were thereby quickened by life. War is waged against them as aliens by the Jews, and persecution is carried on against them by the Greeks, and yet those that hate them cannot tell the reason of their hostility."
That's right - as a Christian, our real citizenship is in heaven! And though we find ourselves in the flesh, we are not to live after the flesh! It seems that Mathetes' description of the lifestyle of the Christians of his time should make us ponder whether we fit that mold or not. And most of all, it reminds us that there is no "salvation" to be found in any government or secular leader, but that our only hope is in the Lord Jesus Christ!
I feel better now.
Sunday, October 21, 2012
A call from team member John Endrizzi to Pat Lehmann of Rochester Harley saved the day. Pat graciously agreed to come in on his day off to establish the baseline jetting using their SuperFlow Dyno.
The following video documents some of the dyno testing. A couple notes about the video; the first thing that you may notice is the ingenious starter system that Joe Taylor came up with. It consists of a snow blower with a go cart wheel attached in place of the rotor. Also noteworthy is that when you see Pat with the welding gloves on, it is because the plug wires kept coming loose from the magneto at RPM. Eventually he was forced to hold them in place during the dyno run. Finding this one issue alone, before making the trip all the way to the salt, was priceless.
So, what was the horsepower? I guess we just don't know. I knew going in that the dyno would probably not pick up a usable trigger from the magneto. The lack of a tachometer on the bike was also an issue. After some initial warm up runs and jet changes, Pat broke out an optical pickup which he set up to run off the engine pulley, but since he had never had occasion to use it before, there was some question as to the readings it produced. The actual readings showed over 120 horsepower at around 4800 RPM - obviously that was incorrect (at no time during the dyno session did the engine reach maximum RPMs). The RPM readings from the optical pickup seemed to be right though.
Tuesday, October 16, 2012
Joe Lieske, aboard his V-Rod based gas dragster came home with the AMRA's V-Mod National Championship. Joe sealed the deal with a big win at the National Finals in Bowling Green. I am a little embarrassed to admit I have lost count of the National event wins he stacked up for the season, but I do know that Joe came home with 4 National Records along the way. In late March and early April he set the 1/8 mile ET record at 5.564 seconds, as well as both ends of the 1/4 mile record: 8.917 ET and 144.55 MPH. In late April Joe lowered the ET record to 8.875 seconds. Congratulations Joe!
On another front, Bill Hofmeister celebrated his first full year of retirement from riding flat track by, you guessed it, adding another couple wins to his long, long list. This time he rode his 900 Iron Head XR to victory at the long running Flying Dutchmen's New Ulm Short Track; not without incident however. During a heat race, problems with the rear brake forced Bill to completely remove the caliper and mount for the Open Twin Main, and since the bike sports no front brake, ...well, let's just say it is pretty plain that old age hasn't dimmed his competitive spirit much.
As for the part about Bill hanging up his racing leathers, some of us were not really surprised...
Sunday, September 23, 2012
Balance the flywheels. Simple enough. In fact if you are familiar with the process you know its normally only about a two hour process. The key word here being normally. Really nothing normal about this motor though. Turning a 1939 engine of any type into a Bonneville racer is not a simple task, but add to the antiquated design, we are also dealing with a small (by Harley standards) displacement which needs to stay that way to remain in the chosen class. In this case, what I am trying to do is make up for displacement with RPMs, and RPMs call for strong and light parts.
Well, we already had some strong parts in the S and S 3-1/2 inch stroke flywheels, and while these flywheels start out considerably lighter than their OEM counterparts at 26-1/2 pounds for the pair of bare wheels, they still needed to be put on a serious diet for this special application. So... to the lathe!
I lightened the shiny new flywheels - a lot! In fact, as sometimes happens, I got a little carried away. Knowing that I was dealing with these tiny little 3-5/16" bore pistons, I "mis-underestimated" how much of the counterweight I could remove. Oops. Well, I had planned to make the pistons as light as possible anyway, so....
First thing was to track down a pair of .080" wall tool steel wrist pins. It seems that I obtained the last set on the planet from Axtell by way of Zippers. Of course they were for a Evo so I had to shorten them as well as hone the pistons for the .001" larger diameter pins. Weight savings on the pins alone was nearly 50 grams. The pistons also went on an extreme diet, with enough material removed from the insides to make any piston manufacturer cringe. I was careful to try to leave at least .180" thickness in the dome though.
I went with 55% for the flywheel balance factor, chosen because that is what the factory used for the XR750. Small motor, short stroke, and high revving - those were the characteristics I hoped EL Bonnie would share with an XR. To get there, not only did the pistons go on a diet, but even such small things as the crankpin nuts were cut down, not to mention adding an internal bevel to the ends of the pin. Before all was said and done, the finished crankshaft assembly (with rods and shafts, ready to run) weighed but 20 Lbs 5 Oz. obviously this motor borders on anorexic.
Before final assemble and true, the flywheels received the same oil shedding, heat dispersing coating as the interior of the crankcases. The underside of the pistons also received the same coating (the idea is to keep the oil moving off the inside of the piston to aid in cooling it. The domes got a ceramic coating as well as an oil retaining skirt coating.
Oil pumps on these old motors are becoming a little problematic. Back in the good old days, it seemed that a guy could always sort through a drawer full of spare oil pump gears to find pairs that would give acceptable protrusion from the body. As time goes on though, the pickings are getting pretty slim. The solution actually results in a better pump than what one might come up with if the drawer of spares was still well stocked. By surface grinding the oil pump gears so that the pairs are of matched thickness, and then surface grinding the pump body, the protrusion of the gears from the body can be "blueprinted" while compensating for the thickness of reproduction gaskets. Bear in mind that we are talking about doing this on a precision surface grinder, not a belt sander. EL Bonnie's pump was in medium poor shape, but the surface grinding treatment brought it back - that and some welding and re-machining on the cover.
That pretty well wraps up the story on the bottom end. The heads had been re-worked by Ron Adamson before the motor came to me, so I'll just comment on the rocker arms. They too received the lightening treatment; or maybe we should call it the "lightning" treatment, since we are dealing with an early Knuck. Once lightened and spec'd for shaft clearance, all that was left was to resurface the pads and treat them with the same oil shedding coating as the bottom end parts.
After all the trials and tribulations which accompanied prepping the engine parts, final assembly was somewhat anticlimactic - in other words it went smoothly. And all finished with nearly a week left for the team to install the engine in the bike and dyno it before leaving for Bonneville!
Thursday, September 6, 2012
The book of Daniel was written in the 6th century B.C., that is; between 500 and 600 years before the birth of Christ. Soon after Jerusalem was conquered by Babylon and its king Nebuchadnezzar, four young men were taken from the tribe of Judah to Babylon. Here they were to be raised in the Babylonian culture so that they would be useful in dealing with the Jewish captives who were also brought there. In today's terminology we might say that they were to be brainwashed. But this brainwashing did not really seem to work as planned. While the four young men did grow up in Babylon and were promoted to positions of authority, they never forsook the God of Israel.
The four young men were named Daniel, Hananiah, Mishael, and Azariah, but they were given Babylonian names. Daniel became Belteshazzar, Hananiah became Shadrach, Mishael became Meshach, and Azariah was renamed Abednego. These last three; Shadrach, Meshach and Abednego, are the focus of our story.
Daniel chapter 3 begins with a description of a 90 foot tall golden image that king Nebuchadnezzar made. The king commanded that at the dedication of the image, when they heard the music play, everyone must fall down and worship the golden image or else be thrown into a fiery furnace. That is where we pick up the story in verse 12:
There are certain Jews whom thou hast set over the affairs of the province of Babylon, Shadrach, Meshach, and Abednego; these men, O king, have not regarded thee: they serve not thy gods, nor worship the golden image which thou hast set up. Then Nebuchadnezzar in his rage and fury commanded to bring Shadrach, Meshach, and Abednego. Then they brought these men before the king. Nebuchadnezzar spake and said unto them, Is it true, O Shadrach, Meshach, and Abednego, do not ye serve my gods, nor worship the golden image which I have set up? Now if ye be ready that at what time ye hear the sound of the cornet, flute, harp, sackbut, psaltery, and dulcimer, and all kinds of musick, ye fall down and worship the image which I have made; well: but if ye worship not, ye shall be cast the same hour into the midst of a burning fiery furnace; and who is that God that shall deliver you out of my hands? Shadrach, Meshach, and Abednego, answered and said to the king, O Nebuchadnezzar, we are not careful to answer thee in this matter. If it be so, our God whom we serve is able to deliver us from the burning fiery furnace, and he will deliver us out of thine hand, O king. But if not, be it known unto thee, O king, that we will not serve thy gods, nor worship the golden image which thou hast set up. Then was Nebuchadnezzar full of fury, and the form of his visage was changed against Shadrach, Meshach, and Abednego: therefore he spake, and commanded that they should heat the furnace one seven times more than it was wont to be heated. And he commanded the most mighty men that were in his army to bind Shadrach, Meshach, and Abednego, and to cast them into the burning fiery furnace. Then these men were bound in their coats, their hosen, and their hats, and their other garments, and were cast into the midst of the burning fiery furnace. Therefore because the king's commandment was urgent, and the furnace exceeding hot, the flames of the fire slew those men that took up Shadrach, Meshach, and Abednego. And these three men, Shadrach, Meshach, and Abednego, fell down bound into the midst of the burning fiery furnace. Then Nebuchadnezzar the king was astonied, and rose up in haste, and spake, and said unto his counsellors, Did not we cast three men bound into the midst of the fire? They answered and said unto the king, True, O king. He answered and said, Lo, I see four men loose, walking in the midst of the fire, and they have no hurt; and the form of the fourth is like the Son of God. Then Nebuchadnezzar came near to the mouth of the burning fiery furnace, and spake, and said, Shadrach, Meshach, and Abednego, ye servants of the most high God, come forth, and come hither. Then Shadrach, Meshach, and Abednego, came forth of the midst of the fire. And the princes, governors, and captains, and the king's counsellors, being gathered together, saw these men, upon whose bodies the fire had no power, nor was an hair of their head singed, neither were their coats changed, nor the smell of fire had passed on them. Then Nebuchadnezzar spake, and said, Blessed be the God of Shadrach, Meshach, and Abednego, who hath sent his angel, and delivered his servants that trusted in him, and have changed the king's word, and yielded their bodies, that they might not serve nor worship any god, except their own God.
There are a lot of thing we might learn from this story, but I'll only touch on a couple. The first thing I would like to point out is that Shadrach, Meshach and Abednego found themselves in this predicament because of their obedience to Almighty God. The 2nd Commandment, as found in Exodus 20 says: Thou shalt not make unto thee any graven image, or any likeness of any thing that is in heaven above, or that is in the earth beneath, or that is in the water under the earth. Thou shalt not bow down thyself to them, nor serve them: for I the LORD thy God am a jealous God...
In fact, these three obviously were not trouble makers; verse 12 tells us they had been put in a position of authority over the affairs of the province of Babylon. It seems that they grasped the principles laid out clearly in the New Testament, that they were to subject themselves to government ...right up until the point where government demands disobedience to God. Then, as Peter states in the book of Acts: We ought to obey God rather than men.
These three displayed their faith in the face of almost certain destruction. In verses 17&18 they say this: ...our God whom we serve is able to deliver us from the burning fiery furnace, and he will deliver us out of thine hand, O king. But if not, be it known unto thee, O king, that we will not serve thy gods, nor worship the golden image which thou hast set up.
In other words, Shadrach, Meshach and Abednego had faith that God could deliver them if he chose to, but even if God did not chose to deliver them from the furnace, they would not bow down and worship the image that Nebuchadnezzar had set up.
One other thing I would like to point out is that in verse 25, when Nebuchadnezzar notices that there were four men walking in the furnace, rather than the three they threw in, he states that the form of the fourth is like the Son of God. I would like to suggest to you that the fourth was not only like the Son of God, but that he was the Son of God.
Because Shadrach, Meshach and Abednego had faith in God they had this promise from Deuteronomy 31:6 Be strong and of a good courage, fear not, nor be afraid of them: for the LORD thy God, he it is that doth go with thee; he will not fail thee, nor forsake thee. In the New Testament this same verse is quoted in Hebrews like this: I will never leave thee, nor forsake thee.
I think it is interesting that Shadrach, Meshach and Abednego faced the penalty of being cast into a fiery furnace here on earth because they refused to sin. We face the penalty of an eternal fiery furnace because we choose to sin.
Rev. 20:11-15 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.
These three men from our story, Shadrach, Meshach and Abednego, had the Son of God with them in the great trial of their obedience and their faith. They had a promise that he would never leave them or forsake them. But do you know what the good news is? If you are a Christian, then you have that same promise. God will never leave you or forsake you.
Just as the Son of God kept these three men from being harmed by Nebuchadnezzar's fiery furnace, he will keep you from the lake of fire. Why? Because your name is written in the book of life; that is, your name is written in the book of life if you will turn from your sins and believe on the Lord Jesus Christ, trusting that he made the payment for your sins by dying on the cross. Then you too will have God's promise of never leaving nor forsaking!
Thursday, August 23, 2012
Wednesday, August 15, 2012
With the mocked up crank assembly in the cases, next up was to get the degree wheel mounted and accurately indicating TDC. If you have never done this, there is slightly more to it than just bringing the piston to the top of the cylinder and lining up the TDC mark of the degree wheel to a pointer. That gets you in the ballpark, but certainly not close enough to base any timing events from. Since there was no head installed, here is an easy way to get the degree wheel "degreed in:
- With the piston at the top, mount a dial indicator and zero the needle
- Install the degree wheel on the sprocket shaft and align a pointer with the TDC mark
- Pick an arbitrary number on the dial indicator (example - .050)
- Rotate the crank counterclockwise until the needle on the dial indicator matches the number you have chosen. Note the exact reading on the degree wheel at that point (example - 9-1/2 degrees after TDC)
- Rotate the crank the opposite direction, past TDC until you reach the same dial indicator reading you chose in step 3 above, and again note the reading on the degree wheel
- If the two reading from steps 4 & 5 match exactly (unlikely), you are done. If they don't match, then loosen the degree wheel and move it to split the difference. For example if your reading from step 4 was 9-1/2 degrees after TDC and the reading from step 5 was 10-1/2 degrees before TDC, then move the degree wheel so that its pointer is on 10 degrees.
- Repeat steps 4 & 5 until both give exactly the same number of degrees before and after TDC
Once the degree wheel was properly installed, the opening and closing specs for the breather gear was checked, looking through the lifter block holes. Rather than go through the process here, I suggest you download the excellent instructions available from S & S Cycle here.
Since a degree wheel was installed, it only made sense to check out the cams, especially given the discrepancy found in cam opening and closing specs due to mis-machined lifter blocks. The lifter blocks seemed to be OK, but the exercise did pretty well make the cam choice for me. The KN420 cam from S & S checked out good. The old Sifton, not so much. One intake lobe showed a 12 degree discrepancy on the opening, 5 degrees on the closing (for a total of 17 degrees less duration) and .020" less lift than it should have, all despite showing no sign that it had ever been run.
Of course since the motor was mocked up as far as it was, it also made sense to clay the pistons to get a sense of how much valve to piston clearance there was. The answer to that question was a lot. In fact, more than a lot; make it a huge amount. That was a bit worrisome, given the fact that I was already apprehensive about the compression ratio the engine would wind up with. The custom built pistons claimed a 10:1 compression ratio but the large diameter intake valves were sure to need a little more radial clearance in the valve pockets. Given my "druthers" I'd have liked to see 12:1 for a starting point.
Time to check the piston dome volume, another fairly straight forward procedure which involves putting some grease on the rings, installing the piston into the cylinder to a measured depth, capping the cylinder with a Plexiglas plate and a burret to measure the amount of oil it takes to fill the void. Then by mathematically calculating the number of cc's that would be in the cylinder without the piston dome (using piston depth and bore) and subtracting the measured cc's with the piston dome in the cylinder, the actual dome volume is revealed.
Entering all the figures into my Engine Analyzer program, which takes into account head volume, piston deck height, head gasket thickness, head gasket bore and adjusting for fire ring and fire ring volume, I came up with a very disappointing 8.25:1 compression ratio. Worse yet, there was no room to shave the heads due to the proximity of the 2.060" intake valve to the fire ring. Now what? I was really beginning to worry that this little 61" motor would be badly over-cammed at this compression ratio.
I decided to call Jim Leineweber of the cam company that bears his name. While he was not wild about the low compression ratio, he said he currently had nothing on the shelf that would work any better. Jim did boost my confidence by affirming the clearances that I planned for the various engine parts, but then I always have been one of those who do well on tests. And it really did seem much like an exam, as he asked what each clearance I planned to use, and then gave each of my answers a "OK- that's good - a lot of guys set that too tight." One key piece of information that I was not sure of, Jim provided. Set the ignition timing to 42 degrees BTDC as a starting point. That tidbit probably made the whole conversation worthwhile; though any conversation with a living legend goes down as worthwhile in my book.
But, memorable conversation or not, it really did not solve my compression ratio problem. In fact it really narrowed it down to the "too deep" valve pockets on the pistons...
Now we come to the "don't try this at home" part of the title of this post. It was far too late to consider having another set of custom pistons built, even if funds had been available for such a thing. But out of the recesses of my mind, I managed to dredge up something that might be of value. Some years ago Mike Roland mentioned to me that he had once welded up the domes on a set of pistons for a drag racer who was on a tight budget. Hmmm. Seemed that a consultation with the best welder I know might be in order. John from PMFR informed me that as long as the pistons were not alloyed with silicone, I should be able to weld on them with no problem. He further reassured me that I would be able to tell the moment I struck an arc - a silicone alloy piston would immediately result in massive amounts of black soot.
Still, what would be worse? Going to Bonneville with a motor down on compression, or missing another year because I screwed up the pistons? It was about this time that I spent a Sunday afternoon watching "The World's Fastest Indian" again; just for a little inspiration. The more I pondered old Burt Munro casting his own pistons in the little shack he lived and worked in, the more I knew I had to give it a shot. Besides, the ceramic coatings I planned to use on the piston domes should give a little extra protection.
That's not to say I wasn't still plenty nervous about it. What if I managed to distort the ring lands? What if I screwed up in some other unforeseen manner? And what might that unforeseen screw up be? Obviously no point in pursuing that line of thought. If I could come up with a possible screw up, it would not be unforeseen.
To make a long story short, the pistons welded very nicely. In fact a steadier hand on my part would have resulted in a nice looking job. But, despite the lack of beauty in my welding, I was confident that it was structurally sound - well...at least as structurally sound as one can be when welding a piece that normal people would not consider mistreating in such a way. So, back to the mill to re-cut the valve pockets to a minimum depth, and then mock up with clay once again. With only a minimum of frustration I achieved valve to piston clearances of an acceptable distance.
Back to the same old drill of cc'ing the newly larger piston domes and entering the results into the computer. To be honest, by that point in time I would have been happy to see 9:1, so I was quite pleased to find we were up to 9.8:1! Next up: balancing the flywheels.
Thursday, July 26, 2012
Did I mention that this motor is being done on a budget? It has much in common with something I would build for myself in that respect; a lot of "spare parts" coming together, in some cases those parts finding their way to the build based on availability and price rather than on fitness.
Before assembling the case halves for the mock up, I put the cam into the gearcase with the cam cover to ascertain how much it bound up in the bushings- the answer being plenty! Still thinking I could get this done quickly, I chose to line ream the cover bushing an extra couple thousands (the particular reamer I use for this operation is adjustable) since that would surely alleviate the bind and keep things moving. Wrong again! Apparently even the additional clearance was not enough to compensate for the mis-alignment between the case and cover. Time to re- think this.
After an appropriate bit of soul searching (to make the decision sound infinitely more dramatic than it actually was) it appeared to be the perfect opportunity to follow the old adage; when life gives you lemons, make lemonade!
The cam choices available are a (new) old Sifton 110 or an S&S FHP 420. Both of them happen to be set up for a Torrington needle bearing in the crankcase rather than a bushing (the shaft for a Torrington will be approximately .0007" larger O.D. than one for a bushing). That means that either the crankcase cam bushing would need to be reamed oversize (the original cam bushing had enough wear that it already fit) or the case would need to be bored for the larger outer diameter of the Torrington. The bearing would have the added benefit of slightly less friction, so it seemed that the logical thing to do would be to use a Torrington on both ends of the cam.
Now, machining to install a bearing in the crankcase is pretty straight forward: indicate in the existing hole and bore it to size. The cover is an entirely different matter though, especially in this case, given there is good reason to suspect it was manufactured with the hole in the wrong place. I decided to create a template. I already had a 3/8" thick aluminum plate with the two dowel pin holes correctly located. By installing the plate on the crankcase half and mounting it on the mill, I was able to indicate in the cam bushing hole, and then going through the bushing hole, bore the aluminum plate.
Once the new hole was bored and a bearings installed in both cover and case, another test fit with right case, cam and cover gave the results I was looking for: a totally free spinning cam! Since I was in cam cover mode, I also tackled the pinion bushing. I chose to go ahead and try installing a new bushing and line ream it, rather than going to extreme measures. Kind of a "why go looking for trouble" approach, and in this case it paid off. Another test fit with the cam cover bolted on the right case and the new S&S pinion shaft with bearings in place resulted in a very pleasant surprise. Absolutely no binding even with only .0007" shaft to bushing clearance! It appears that the cover manufacturer managed to get half of the bushing holes in the correct place.
Saturday, July 14, 2012
As soon as Joe dropped off the engine, it became apparent that they committed no sacrilege by turning it into a racer. Nearly every square inch of the '39 cases showed evidence of welding repairs. If they could talk, these cases would probably have quite a story to tell. With Joe's permission, I decided it would be worthwhile to do some reinforcement modifications. I added a gusset to the left side of the left front motor mount (which showed evidence of at least one previous repair). Early Knuckle cases are also known to be weak on the left side in the cylinder spigot area. My solution was to weld 3/8" plate to that area, windowed just enough to leave the serial number pad intact.
Moving on to the the inside of the cases, windage is always a concern - at least to my mind. The "pocket" in the right side case quite obviously performs no function other than to save a bit of aluminum during the casting process, and I have always pondered what to do with it. What, if any, effect on windage this pocket has is any one's guess. On the other hand, when it comes to racing, I am a firm believer that the difference can often come down to a matter of adding together all the details. I've heard it before: "Do you really think that will make a difference?" My answer is usually, "We'll see." But the more honest answer is no ....but hopefully when it is added to the other dozen things that are too small to make a difference by themselves, it will!
A couple of thin aluminum plates cut to fit and welded into place smooth out the interior of the right case half. The next step toward minimizing windage was to polish the interior of the cases, including the gearcase. One of the final steps before final assembly on the case will be to treat them with TLTD, a oil shedding thermal dispersant coating.
Now you see it ...
Now you don't
So, if all the previous repairs had not distorted the cases, it was a good bet that with the welding I did, there was reason for concern! Besides, one of the keys to making this motor fast will be to keep the friction losses as low as possible. The first step to ensuring that was to mount the left case to the mill and indicate in the pinion shaft race hole (races removed). Once the indicator showed that it was centered in the hole, I gently installed the right case, torquing all the case bolts. Taking a reading from the indicator in the right side case race hole, I was far from shocked to find .012" runout. A +.025 race in the right case was the cure.
Next, with the cases still bolted together, I decked the bottoms of the motor mounts enough to insure they are true, and then did the same with the cylinder mounting surfaces. Before giving the mill the rest of the day off, I also machined the breather gear bore for the +.030 S&S gear, removing 70 years worth of damage in the process. Installation of the new crankcase races, and line lapping them to size pretty well brings us up to the present. Next is a mock up to blueprint the breather opening in the case and see what kind of piston deck height we are dealing with. To be continued ...
Sunday, July 1, 2012
As shown at the end of the above passage, marriage is a symbol or picture of Christ and his relationship with the church. That would seem to help explain why there are so many dead set on destroying that symbol today. This passage in Ephesians is given to help us understand Christ's relationship to the church by holding up a biblical marriage as an example. Sadly, in the wicked world in which we live, the average marriage bears little resemblance to what scripture tells us it should look like. Still much truth about the nature of the church can be found here, such as Christ is the head and the church is subject to him. Christ loves the church and gave himself for it. He uses the word of God to clean and sanctify the church to make it holy, and even that there is an intimacy between Christ and the church that will be found only in that relationship.
If you are a Christian, this should lead you to a couple of conclusions. One is that your own marriage should reflect the values presented in Ephesians 5 so that it does not present a distorted image of Christ and the church to the world. The second conclusion a Christian should draw is that the church they belong to also should reflect the values presented in Ephesians 5 in it's relationship to Christ, so that it does not present a distorted image of marriage to the world.
Friday, June 8, 2012
A trip to the mill took care of that, but the exhaust valves were another matter entirely. Not only did they not have enough valve to piston clearance, they actually touched the piston preventing a full revolution. This is a pretty unusual situation, and as such, it was unforeseen by me. And since it was unforeseen, I had already taken material from the inside of the piston domes to lighten them. Not knowing how much material would need to be removed from the valve pockets, but knowing I did not have much to work with, I chose to sink the exhaust valves deeper instead. I started by going .080" deeper to see if that gave at least some clearance (and it did), and then went back and cut the seats again to give a finished clearance of .100". A new pair of custom exhaust valves with shorter overall length have been ordered to put the stem protrusion back into a rocker geometry friendly state. Incidentally, the exhaust pockets also needed a little more radial clearance than they came with, despite the fact that I did not increase the exhaust valve size.
As I hinted at in my last post, the flywheels were cut down a fairly radical amount, making the balance trickier than usual. Normally when balancing flywheels, the counterweight section of the flywheel is the heavy spot, and one simply drills holes at the heavy spot to bring it into balance. When the flywheels start to get very narrow, the "counterweight" shrinks. With big bore pistons it is easy to come up with a situation where the "heavy" spot in balancing is on the crankpin side - not the place you want to weaken by drilling balance holes. After I had lightened the pistons as much as I felt was safe, that was still the situation I was faced with. Rather than creating a "swiss cheese" effect in the crankpin area of the flywheels, however, I used an end mill to "skim" the required weight. After multiple trips between the mill and the balance table, the flywheels came into balance with no holes drilled whatsoever. Sorry, but I neglected to take pictures.
As for the rest of the motor, the inside of the crankcases (including gearcase) were treated to an oil shedding coating, as were the flywheels once the balancing was complete. Again, I neglected to take pictures.
Once trued, the flywheels were installed in cases and the oil pump and gearcase assembled. As I await delivery on the custom exhaust valves, final porting work is the next order of business. The intake ports, as mentioned in a previous post, have had the floors welded up. Due to the large valve size (2.125" vs. the 2.0" the heads came with) a larger port opening size was in order. The port diameter that I chose was 1.900" (89% of the valve diameter). This of course required major modifications to the intake manifold, which included relocating the flange bolts. I will try to include some pictures when the heads are nearer completion.
Fortunately the owner gave me a bit of a reprieve on finishing up this motor, which has been a real blessing since I have a boatload of other work that needs to be finished up soon, not the least of which is a motor that is headed for the great salt flats dyno in Utah. Now, with that "teaser" I had better abandon the keyboard for more productive endeavors.