How to make self-aligning pillow block bearing (for jackshaft) non-self aligning?

[fishyfish777]

After successfully getting the chains down to the right length and getting the 99cc bike up and running, I decided to give it a little test run. However, a few feet walking down the road and my right-side drive chain popped off.


When I looked down, the pillow block had "self-aligned" and adjusted the angle of the jackshaft to around ten degrees, throwing off the chain. I hadn't even considered the possibility, but now that I think of it there IS a little space between the bearing and the housing that I can see a little nub through.


So my question is this: Will filling this with JB-Weld stand up to the twisting force of a 99cc engine? If not, will the bearing hold straight if I just get someone to weld it or would it likely warp under the heat of welding? (It's a big cast iron 5/8" pillow block bearing)

One of these. You can see the gap I'm talking about in the black space to the lower right hand corner between the bearing and the housing.

 

[Erich_870]

We need a picture of your bike and how your bearings are set up.

A self aligning pillow block bearing is usually designed to allow the bearing to swivel inside the block housing, but it should not have room to rock or slide front to back.

This kind of bearing is for situations where the block can't mount perfectly square to the shaft. If you didn't mount your pillow blocks directly across from each other, the shaft will still slip into both bearings, BUT your sprocket will not be aligned with your chain.

Post a close up of your bike and then we can figure out the problem.

Erich

 

[wayne z]

That bearing is supposed to swivel in the pillow block. It'll prolly br kinda stiff and hard to move with your bare hands. The slots in the housing are for removing the bearing by swiveling it complety sideways. Don't pack any JB in there.

 

[wayne z]

Do you have two pillowblocks on the shaft? Only one won't work.

 

[Erich_870]

Do you have two pillowblocks on the shaft? Only one won't work.

x1,000,000

You should have two pillow blocks...

Erich

 

[scotto-]

Two pillow blocks even this close together works just fine. When spread further apart works even better. A single pillow block without another support of some kind will cause problems.