1941 Front Fork Upper Bearings

[41Chief]

Hello,

I am redoing my 1941 Chief. It has a leaf spring front end. I removed the front fork to blast the frame and repaint it. That came out OK. After repainting the front fork, I am not trying to put it back on.

The lower fork bearing is a tapered bearing. The upper bearing has 21 1/4 ball bearings which I replaced. The lower bearing is OK. At the moment, I am having a very difficult time trying to get the fork put back on as the 21 ball bearings at the top keep getting miss-aligned as I try to tighten the nut that holds the fork to the frame. I put the fork into the frame and tied it up so that it did not slide out. There is like a half a race that goes into the top part of the frame that the center bolt of the triple tree slides into. The nut that holds the fork on has the other half of the bearing race. I tried it with the bearings sitting on the bottom half race as well as the top half race with bad results both ways.

Is there some sort of secret way that the fork goes on without too much hassle, or even an easy to install conversion to a caged bearing for the upper part.

Thanks for any tips.

41Chief

[1950Panhead]

The original design is poor, kiwi has a better bearing, machine upper race off.

[pisten-bully]

Have you tried layering some grease onto the race to hold the balls in place?

[tfburke3]

I like your setup with the tapered lower.I would also use original neck race and nut if they are like new,and the kiwi setup if upper parts worn.It helps if the nut spins down the stem freely by hand.Wipeexcess grease.should not be that hard.Good luck
Tom

[41Chief]

Thanks for all the replies.

I have reached out to Greer and Kiwi regarding their upper bearing upgrade and not heard back. Both of their websites say that 'some' machining is required. I would assume that they are both selling the same bearing kit.

Does anyone know how much machining is actually required and what type of machining it might be? I do not want to have to yank the powerplant back out to take the bare frame to some machine shop if I can avoid it.

[tfburke3]

I never used the upper kiwi set up but I had planned to once.The machining is only on the nut race,facing it off flat.I tried with my small table top lathe and it was to hard for my tooling.Probably need to be ground off.I really dont understand why if your parts you have been attempting to assemble are in good condition you dont proceed.In my opinion the original setup is just as good but replacements arent available so kit allows the use of your original nut and a new bearing.
Postion the fork centerd,place balls in grease and screw on nut.
Have fun
Tom

[41Chief]

My parts look OK to me. On my bike, the upper race has about 1/8" +- gap between itself and the triple tree. And the race does not prevent the ball bearings to move inward towards the triple tree. So, when I tighten the cap nut and it presses against the ball bearings, they have a tendency to move inward out of the race. I cannot find a good picture of what the race is supposed to look like, perhaps mine is worn out or defective. I have used LOTS of heavy grease and made sure that the triple tree is centered on the frame as I tighten the cap nut, but it as not achieved success. It just seems like going with a modern, sealed bearings will solve the problem.

I do appreciate you clarifying what machining is required. I figured it might involve the cap instead of the frame. For the $15 that the sealed bearing costs, I am going to try that. I think my milling machine will handle it and if not, then I can just use a grinder.

Thanks.

[tfburke3]

something sounds off.When the balls are in the race when the nut comes down to contact there is no room for the balls to move inward.
Maybe post some pics or good luck with the modification.
Tom

[pisten-bully]

something sounds off.When the balls are in the race when the nut comes down to contact there is no room for the balls to move inward.

I was thinking the same thing, the “tube” that comes up through the neck shouldn’t have that 1/8” space between it and the race, should it?

[41Chief]

Tom,

I agree with what you are saying. It should go on no problem. It was on before with the existing parts until I took it down to the bare frame to blast it and repaint it. The parts all look good and the ball bearings are brand spanking new, although there did not seem to be any problems with the ones that were there before.

I took some measurements with my el-cheapo harbor freight digital caliber. The stem is 1.125 (1 1/8") in diameter. The inside diameter of the race is 1.133 so there is some gap between the inside of the race and the stem. The entire front end (leaf spring) is on the bike, less the fender and the wheel, so, it is quite heavy. With the fork up as far as it can go, it is most definitely not centered in the race, but I can move it to get it centered. However, with only 2 hands, it has been a challenge to keep it centered while I screw the stem nut in. I think what is happening, is because it is not perfectly centered, the race on the stem nut is causing the ball bearings to get skewed and move towards the stem.

It is after dark here at the moment and my shop is not lighted all that well. So, I am going to rig up some straps in the morning to get the stem as centered as possible and give it another go. If I decide to give up, I am going to order the bearing tomorrow. I hope it comes with directions so I know how much shave off the stem nut.

I am wondering, if perhaps I should not raise the front end up all the way at first, but get the stem nut and lower bearing on correctly and then use the stem nut to raise the front end up to get the lower bearing seated properly.

Clint
===

[tfburke3]

pics dont look bad.lower race maybe worn but hard to tell.If you want put the assebmby together,balls ,nut and race and see how they feel.
Tom

[41Chief]

Thanks for all the advice. With another set of hands I was able to get the triple tree aligned properly and screw the cap nut on and it seems to have done the trick. The tolerance for alignment must be very tight.

If I was restoring a complete basket case I would probably go with the aftermarket sealed bearing.

[exeric]

Getting the fork in, and the top nut threaded into place by yourself is a sure way to pulled muscles, or a trip to a chiropractor. Good thing you had help. With good bearings, and the proper pre-load, the leaf spring Chief becomes a joy to ride. Glad you got it all sorted out.

[Rubone]

Any fork, Indian, H-D, or any other, must be installed with no weight on it. A common mistake is letting a chassis rest on the wheels before the top nuts are installed. Bad idea, the weight of even a few components will tweak it out of line. The rule is "no load" no matter what.
Glad you got it sorted.