SOTrident 900 drive noise

My 1993 Trident 900 has done about 36,000 miles (that's right, it's not
been heavily used in its 14 years...)

I notice a certain amount of drivetrain noise, especially in top gear, but
I'm not sure what part of the drivetrain is making this noise. It's a
gentle but slightly graunchy-under-load whining sound, usually I would
have thought indicative of worn gears, but wondered if it might be wheel
bearings. The noise lessens if I de-clutch and coast, but it does
markedly increase if I apply throttle under load. The noise is evident in
4th and 5th gear too, but less easy to make out in lower gears because the
engine noise drowns other sounds out. All of this is why I'm not sure
if it's wheel bearings or a worn gearbox.

Any thoughts, gentlemen? (I use the term loosely

Ta.

 

chain drive, ain't they...

does the 'box share the engine oil or have its own?

 

Sprocket carrier bearing?

JB

 

Nylons in the gearbox.

Arfur.

 

Thus spake Austin Shackles () unto the assembled multitudes:

Shares it.

 

Thus spake JB () unto the assembled multitudes:

I did wonder whether it might be the gearbox sprocket.

I did run it with a higher-ratio sprocket set for a few years (two extra
teeth on rear sprocket I think). I wonder if the increased load might not
have been so good for the 'box.

 

That's putting less load on the gearbox sprocket. You won't kill a box loke
that, unless you overtighten the chain to extremes.
No point guessing. Have the wheel out and check all 3 bearings. Then work
your way forward form there.


JB