I have been reading about the benefits of using an assembly bearing on the pinion to ease the gear setup process. Most people have either used an old bearing or bought a new one and honed it out a few thousandths of an inch so that is slides on/off the pinion without having to use a press each time.

If the assembly bearing is replaced with a normal, pressed-on bearing during the final assembly, won't the difference in the tolerances of the 2 bearings cause the gears to mesh differently? Obviously very minute changes to the thickness of the pinion shims can affect the gear pattern so isn't using a different bearing in the final assembly bearing likely to do the same?

Thanks in advance,
Matt

 

Yes, you are exactly right. That is why I don't use them. Many people don't have a press, so it helps them get close by using one of these bearings, but you always must check the pattern again after the real bearing has been installed and make any final adjustments to the shim thickness. I would never recommend using a used bearing for this.

 

I have done it quite a few times, never a problem. I always used the same bearing manuf. and used a honed out new bearing. the tolerances between them are pretty tight, I've never had the pattern go off to require new shimming to get it right again. If you want to use the final bearing and have to pull it off again you kneed a bering puller with as thin a "knife" as possible or you'll run the rist of warping the cage, which imo is a worse option than using a set up gear.