is there any sort of adjustment/shim for the drive shaft gearing

96 st1100, abs/trc
haven't torn into it but wondering if there is any sort of maintinence/adjustment related to the final pinion and ring gear at the end of the drive shaft. the manuals don't seem to speak to this. only the oiling of this area. is there some amount of lash in this setup?

demaris said:

...any sort of maintinence/adjustment related to the final pinion and ring gear...

Click to expand...

Not unless you'd taken it apart or it suffered some sort of failure...
Adjustment procedures (i.e. after a rebuild) are covered in the Common Workshop Manual; the ST manual/s only focus on model specific topics/items.

Worn rubber/aluminum inserts can cause a bit of 'lash'... when was the last time you checked them?

haven't checked yet. new purchase. bike is in great condition but there is a bit of what would be a "loose chain" effect when lightly going throttle on to idle and reverse. i suspect that i am over thinking but just wondered if there was adjustment. may be normal, maybe the u-joint. just curious on anybody's take.

st1100y, thanks for the tip. i had only looked at the haynes manual. i see that the official shop manual has all the info.

shaft drives have a bit of loose backlash that is normal, all your old rear wheel drive cars always had some noise from drive to reverse. Shaft drive has some issues that are outweighed by the minor (little to none) maint factor

My 1991 has no appreciable lash, but it only has 19000 miles. With the bike on the center stand and in first gear, rock the rear wheel back and forth. I'm not sure what the normal play is but listen for clunks or clanks.
Likely causes have mostly been mentioned above...rubber cush drive units are a likely suspect. Check out the condition of the drive splines that fit into the rear wheel hub. If a PO wasn't careful about lubing these at every tire change with moly grease, they can wear. Could be the spline in front of the final drive that connects it with the final drive shaft...lack of grease can result in wear and play/clunking. If a clunk is coming from the right side of the swing arm, close to the engine, could be the upper upper splines or the universal joint have play. Just some things to consider. When I brought my 1991 home last August, I pulled all this apart, checked, cleaned, and re-greased everything...it had been sitting for most of the previous 20 years and I was concerned about the effects of time.
If you ever need, there IS a Youtube video showing how to shim the bevel gears in the final drive. Not likely that you would need to do that.

demaris said:

...there is a bit of what would be a "loose chain" effect when lightly going throttle on to idle and reverse...

Click to expand...

likely worn cush rubbers/aluminium inserts, and check condition of drive splines as others already suggested.

As long as nothing inside broke (like a thrust-washer cracking apart so bits got meshed through the gears), the final drive rarely requires rebuild...

How many miles on your bike ?? Besides the cush rubbers, maybe your u-joint has some slop.

+1 for worn cushy drive rubbers, I've not long replaced them at 68,000 miles, they practically fell out, made a big difference to the back lash on the rear wheel.
Chris.