Wednesday, December 31, 2008
Sunday, December 21, 2008
- Starting at the back of the assembly, a 5 stud clutch hub is a worthwhile upgrade for performance use. Whether you upgrade your existing hub, or buy a new one may come down to a money issue. If you can change the studs yourself it may be cheaper to do that, but if you have to pay someone to change the studs, it may be just as cost effective to buy a new 5 stud unit.
- Replace the "clutch hub fiber disc" with the "Nylatron" unit. In normal use, this fiber disc works as another clutch plate. That means that it is susceptible to making the clutch drag if there is insufficient release between it and the back of the clutch basket. Since this plate is behind the clutch hub bearing, it is also inordinately susceptible to grease from that bearing, further enhancing the probability it will drag. Whether the Nylatron disc was designed this way or not, what I like to do is treat it like a bearing rather than a clutch plate. I grease up the Nylatron disc on both sides to make it unlikely to give any drag. An added bonus to the Nylatron is that it is "full floating", so you don't have to worry about riveting it in like the stock disc.
- Next, in place of the stock clutch hub bearing retainer, install a "Ram Jett Retainer". I believe this little item is named after its originator, but is now being sold generically by all the major parts wholesalers. This little item is a rigid plastic/nylon disc that goes on after the basket is installed on the hub. It is installed with snap rings in place of the stock "spring clips". Depending on the indexing of the disc, it will give more or less end play to the clutch basket. Remember what I said about the Nylatron disc being used to make the assembly like a bearing rather than another clutch plate? The Ram Jett Retainer forms the other end of this "bearing assembly" and controls the end play. Controlling the end play eliminates the basket from "walking out" and causing clutch drag
- Clutch plates. Besides making sure that the plates are in good shape (not oil soaked or glazed) the other consideration is what use the clutch will be put to. For even hard street use, I would still recommend cheap replacement fiber discs. I remember (from back in the old days) one particularly successful street class racer used a particular brand of cheap aftermarket fibers with great success. Due to having a high horsepower motor along with a street tire, he slipped his clutch while launching the bike, managing a near perfect blend of RPM and traction. Sort of like a slipper clutch, only with the rider's clutch hand providing the magic. After every pass, he would swap the clutch plates out, allowing the most recently run ones to cool. I wish I could remember what brand plates he said he ran, because he did say not all of them worked equally well.
- Working our way out, an aluminum pressure plate will almost always work better than the original stamped steel one. They don't flex. They are also surprisingly affordable.
- The -41 clutch springs will give more pressure than the later hand clutch versions. Keep in mind that this will make your lever pull a little heavier though (that is why they changed them when they eliminated the mousetrap; also known as a hand clutch booster)
- The clutch spring retainer is the steel disc at the outer end of the clutch that the 5 nuts (now that you upgraded from a 3 stud hub) tighten. It will have 5 "nubs" that the special nuts index on. You're going to want to grind those nubs off. Discard the special nuts and use nylock nuts in their place. Now you will be able to get a fine adjustment on the pressure plate rather than in 1/2 turn increments as the special nuts provide.
- Now if your bike is going to be used mostly on the street, and you have no clutch drag, you are all done. If, however, this clutch is going to see some major drag racing use, you might want to keep reading. Most clutch problems on the drag strip are related to dragging, not slipping. Even a clutch with perfect street manners will tend to drag when your bike is staged and at 4000 RPM or more. Remember, all the clutch needs to do is "pull" your bike an inch or two and you have red lighted. Besides, it is pretty much impossible to cut a good light when distracted by a dragging clutch. The solution (if you have addressed all of the items here and in the first post) is to add more release travel. As I mentioned in part 1, you can remove the hand grip to allow the clutch lever to move farther. A layer of electrical tape will make the bar a little less slippery without a grip. One last trick. You can also add a little more travel to the clutch release by shortening the release arm (the lever that comes off the top of the kicker cover). You should be able to take about an inch out of the center of this arm without adding too much misalignment to the cable. Remember, this will also make for a heavier lever pull.
There you have it! All the tricks and tips that I know for the 4 speed clutch... well, at least all of them I remember. Will this solve all of your clutch problems on the street? I think so. On the strip? To a point. Even with a more modern clutch, I found that a 6000+ RPM launch required a line lock on the front brake to avoid being pulled through the lights. But for a 60 year old clutch design, I think you'd have to agree it was a good one.
Wednesday, December 17, 2008
It seems that a commenter by the name of Steve has some real issues with Christians opposing "gay marriage". In fact the long and short of his various comments come down to this. It is hypocritical for Christians to spend more time opposing "gay marriage" than they do in opposing the liberalization of divorce laws since both of these things weaken the institution of marriage. The exchanges in the comments section have been numerous and heated.
I have a lot of thoughts and opinions on these subjects, but to narrow this post down to a manageable size I want to comment on only one aspect. To the cry of "Hypocrite! Hypocrite!", I answer; Guilty! Guilty!
You see, that is what real Christianity is all about. Being a hypocrite. Despite God's work of giving us a new spirit, redeeming us by his blood, and making us free from the penalty for our sins, we are still stuck with this flesh. And as long as we are stuck with this flesh we will continue to sin.
Paul touches on this in Romans 7:18-24 where he says: "For I know that in me (that is, in my flesh,) dwelleth no good thing: for to will is present with me; but how to perform that which is good I find not. For the good that I would I do not: but the evil which I would not, that I do. Now if I do that I would not, it is no more I that do it, but sin that dwelleth in me. I find then a law, that, when I would do good, evil is present with me. For I delight in the law of God after the inward man: But I see another law in my members, warring against the law of my mind, and bringing me into captivity to the law of sin which is in my members. O wretched man that I am! who shall deliver me from the body of this death?"
So, if your complaint is that Christians are hypocrites, then you are right indeed. But being a hypocrite does not relieve a Christian of his duty to proclaim God's word; all of it, even when it is not convenient. This is a Christian's duty, even when he will be called a hypocrite and unloving for doing it. Yes, a Christian is to proclaim God's word in as loving a manner as he can, but what could be more unloving than not proclaiming it at all.
I, for one, am longing for the day when I no longer have this sinful flesh to deal with.
Saturday, December 13, 2008
As I alluded to in an earlier post, I plan to build a Knuckle using a set of dual Linkert heads that I already have. The first thing I did after committing to building this bike was to order a set of new STD replica Knuckle crankcases. I know, I know.... I've already ruined it for some of you! Sorry, but there is just no way I can justify the cost of a set of original cases, not to mention the inherent weakness in an aluminum casting that has seen at least 60 years of abuse. I hope that you purists will find it in your heart to forgive me.
Another major piece has been donated by my good friend Watso. After reading my blog he called me to offer a replica Panhead frame. Needless to say, that is a major step forward in the project, and Watso's generosity makes the whole thing much more financially feasible for me.
Sorting through my stash of used parts I came up with these to be added to list of parts I plan to use:
- a set of XA (pre '74) rods which I will have shot peened and rebuild
- breather and circuit breaker drive gears
- a pre 1940 oil pump (customarily used for drag racing because of their lower volume)
- 3 out of 4 rocker arms and all 4 shafts
- a front rocker box
- a front lifter block
- 16" spokes and rim for the rear
- a few Linkert carb bodies to experiment with
- the complete vintage drag racing 2 speed transmission from Don Jone's 1950 drag bike, "The Gorilla". I will need to freshen it up, but it will be the real "centerpiece" of the bike.
- a clutch hub and basket
- a new reproduction Panhead rear cylinder
- damaged inner and outer primary covers to be modified into a primary chain guard
I have new Rowe exhaust valves and guides. On the intake side I have a set of Screamin' Eagle 2.080" valves (selected because of their shallow tulip and being the correct size for the existing "choke" in the heads). The 5/16" stem diameter of these valves necessitate fabrication of custom valve guides, for which I have already obtained the blanks from Rowe. I have also ordered a set of flywheels from Truett & Osborn .
That still leaves me searching eBay for a few items:
- a rear exhaust rocker arm
- a rear rocker box
- a rear lifter block
- a cam cover
- a magneto (though for the price they seem to go for it may make more sense to buy a new one from Joe Hunt rather than buying used and then sending it out for a rebuild)
At this point in time, my plans are to buy a reproduction springer, which will help to give the bike that real vintage look. I will also likely buy a pair of reproduction star hubs, since it seems like you always have to take five used ones apart to find one good one. Rear fender will likely be a cut down reproduction. Cam? Leineweber without a doubt. The only question is whether it will be the #3 or the #5 grind. I plan to get a little further with the heads before making that decision.
One thing I am still up in the air on, is what fuel tank I should use. I toyed with using a Hummer tank, but seeing what they bring on eBay may have ruled that out. Thoughts?
By the way, this bike has found a nickname before it has even had its first two parts permanently bolted together. Vinnie.... short for vintage drag bike.
Tuesday, December 2, 2008
But not for the last week and a half!
The laptop is in for major repairs, and not due back until the 8th. The silver lining is that I had purchased an extended warranty on it (something I would not normally do). I guess having the warranty put off the day when I switch over to a Mac. Microsoft has become something of a dirty word around our house, with the untold hours lost due to programs that don't work correctly. And then there are the viruses.
I have to admit to a little nagging suspicion in the back of my mind wondering whether it is the people at Mac who spend their evenings producing viruses that attack PCs. Nah....couldn't be....
Anyway, that is why I haven't posted for a while. Hopefully that will change soon.