Bearing "race" puller, final drive bevel

Did you measure and alter the shim stack?

or just go back with what was there?

I re measured the tolerance of the main bearing when fitted and it was identical to the old one so I left it alone, I know there is some theories that they where not shimmed properly out of the factory but honestly the last setup lasted over 40k miles I see little reason why the rebuilt drive will not do the same and that is fine with me. Plus I do not know of anyone in the UK doing a FD re shim exchange program as Bruno does in the US..
 
If I'm reading this correctly Triniriderz you had play at the rear wheel but the big bearing looked sound. That may be because the unit was under shimmed allowing some movement in the taper roller which is substantially magnified at the wheel rim. I believe a lot left the factory over shimmed which puts far too much lateral load on the ball race which is what causes failure.

I'm no engineer but I can't imagine why the designers put a ball race on the opposite side of a shaft to a taper roller. The one needs some lateral preload to function correctly, the other doesn't like lateral loads. Looks like a bodge.
 
The taper bearing controls the float of the that end of the shaft, holding it on the centerline of the shaft.
The ball bearing just holds the shaft in place and provides a bearing service for it to rotate on.
The shim stack controls the mesh of the large gear and the taper bearing limits the depth of the mesh opposite to the shim stack.

Two taper bearings could have been used I suppose

Just my thoughts, am sure some one will chime in with other opinion and ideas
 
Just ordered two sets via Paypal for these bushings. People are giving good responses for these alternative materials.
Anybody interested in a set in the north west, let me know.


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Well a chance meeting on Sat with a guy at High Beech had my bike round his place yesterday with a setup to measure the play in the newly rebuild final drive..


Whilst I was fitting a new set of Venhill Braided Front lines and a Mitas E10 rear tyre we got the final drive removed and he went to work..

It was actually very easy to measure and had I of known of this procedure I could have done it myself.

The play in the newly rebuild FD is 0.08mm and I think he said the upper limit was 0.10mm, that puts it within spec, unless BM was wrong again with this value??.. I even contacted the previous owner who was a old acquaintance and he confirmed the FD had never been touched in the previous 34000 miles prior to my purchase.

I am doing a trial run to Russia early/mid 2017 before the big trip, I will keep a eye on it and go from there.. If I need to do the rebuild every 40k then so be it, the bike is used for a lot of off roading and greenlaining so higher wear on parts is to be expected. The bike owes me peanuts in the grand scheme of things I can live with that.

Regards
 


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