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Please see the attached technical bulletin. It may be helpful to some in understading the technical challenges with these arrangements. There is plenty of this stuff available on www, just trawl through to find the article most pertinant to your issue. 1 thing though, it is not possible to replace any components in a bevel gear arrangement without being able to measure and verify things such as backlash and preload. Both these require jigs in most cases, so without the tools, don't attempt the work as a positive result will be purely by chance. If you drive fails, and you suspect it to be the over shimming issue, then simply replacing a bearing will not solve the problem, and guessing the shim reduction will also not gaurantee a positive result. These are highly technical gear arrangements that require accurate set-up techniques. Once correct, the service life will be there. Curtis (Charlie VT) and some others have spent a lot of time (and $$$ I'm sure) understanding this problem and tooling up to help improve the reliability of this troublesome issue which, put into perspective, still only manifests itself in about 4% of the LT population.
 

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Thanks for posting this link.

Fortunately, there is rarely a need to adjust the pinion/bevel gear setup in the K1200LT final drive; it is not a problem area.

Very often, when the "classic" crownwheel bearing fails, the rider stops riding soon after feeling roughness and the tapered rollerbearing isn't damaged.

When replacement of the tapered roller bearing is reqired, it is complicated a little by the fact that the shim that adjusts the gear lash is underneath that bearing, so when replacing the tapered rollerbearing the gear lash should be checked. In my experience, due to the consistency of bearings, I haven't had to change the gear lash shim.

Rebuilding the input pinion assembly requires rechecking the pinion/bevel gear tooth contact pattern. Fortunately, again, this hasn't required reshimming, even when replacing input pinion shaft bearings.

The variables that affect the shims that set tooth contact pattern and gear lash seem to be related to variations in machining of the housing, and not variations between bearings.
 
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