Jackshaft heavy duty freewheel breakdown

Discussion in 'Transmission / Drivetrain' started by Frankenstein, Dec 22, 2016.

  1. gary55

    gary55 Well-Known Member

    15 bucks at stake here.:cool:

  2. Frankenstein

    Frankenstein Well-Known Member

    Was only 10, and it was a good bet, as you see
    And a bit more fitting..
    Last edited: Dec 28, 2016
    gary55 likes this.
  3. Frankenstein

    Frankenstein Well-Known Member

    While doing a closer inspection and tear down of my replacement bearing I ended up losing a single ball bearing... Kinda frustrating, they are only an 1/8th inch (3.17mm) in diameter, I was looking towards replacing the entire rack of balls with ceramic anyway. I think this with the stainless steel races will create a very resilient bearing once the races break in (the outer race is intentionally a couple thousandths of an inch larger, the now very thin race actually compresses to a slightly smaller and snug fit when assembled in the freewheel)

    I could just buy a regular proper fitting bearing but the challenge is more worth the experience than just getting a pretty standard bearing..

    I will need to make the bearing profile smaller now. It's currently 6.5 mm thick but I have to cut down to 5. This means I will have to loose a rubber seal seat so the bearing will be unprotected on one side. Ceramic Ball bearings and a set of non-rusting stainless steel races will obviously take a serious beating before failure. If anything harder than the extremely surface hardened stainless steel gets in the bearing the balls will pulverize it and make it part of the bearing race. If something like diamonds get in my bearing then I might get screwed but what's the chances of that actually happening.

    The freewheel still uses a 3rd bearing seal (which I should probably correct one of my earlier posts, seems that a 6808 bearing seal is what's used on one of the outer sides of of freewheel as a design feature. Not bad actually.) and has a rubber o ring that uses the lock ring as a sealing surface.

    So far only 10 bucks for the bearing, and my time to heavily modify it. It also uses a nicer nylon or semi-ridged plastic bearing retainer. This is higher speed and lighter weight. Only temperature could destroy it with ease but it's not a hot running part.

    The ceramic balls would run just under 9 bucks with free shipping. As far as I can see that's 19 bucks for a bearing that otherwise would have to be purchased for 25. It's also going to be much more durable than its original. A bearing like that could cost upwards of 50-70 bucks for the same basic thing.

    I would trust it to ride on for a long time. What's nice is the snug fit when freshly rebuilt will only get loosened as far as it will actually need to be. After a certain time the forces will balance out for the happy medium without worrying about my bearing exploding.