I’ve been chasing a deceleration whine on my 04 vstar 1100. My rear mid shaft nut looks good and is staked. My final drive fluid was low with 6oz that came out after an overnight drain. I am at a loss trying to find this whine. Might have to pull the rear wheel and degrease everything and see if their is any issues going on. I just want to ride this bike.
Dsmooth12
- Reaction score
- 523
I think it's one of the two sets of right angle, spiral bevel gears.
You won't catch me calling the rear set of gears and their housing in the wheel hub, a "differential" though. That name means something very specific, which is based on "difference". With only one drive wheel, don't need a difference, and shouldn't call it a differential, cause it isn't.
You won't catch me calling the rear set of gears and their housing in the wheel hub, a "differential" though. That name means something very specific, which is based on "difference". With only one drive wheel, don't need a difference, and shouldn't call it a differential, cause it isn't.
- Reaction score
- 523
If that's your bike in the video, sure sounds like gear whine to me.
The whine you hear from a spiral bevel gear set is the sound of the teeth engaging and disengaging, and the frequency will be proportional to the rpms, and generally much higher than the frequency coming from a drive shaft issue.
Spiral bevel gears will whine because:
- there is too much axial clearance,
- bearings are worn
- gears are worn
- lubrication is inadequate
Besides properly filling the rear drive housing with the correct lubricant, if you have any reason to think that the gearsets have been disassembled since they left the factory, they may have been reassembled incorrectly. Individual sets of gears are matched using different thickness shims. Here's the diagram for the rear angle gears: You can see that various different thicknesses of shims are available.
![Image]()
If, some mechanic was to rebuild a gearset using a one replacement gear, for example, the original shims would no longer be appropriate. Similarly, if there were two shims present, but one got left off in a reassembly, the clearance would be excessive. Gears want to be held in precise alignment, with some, but minimal axial clearance for each gear in the set. Same goes for the front set.
I'd want to be sure which end the whine was coming from, so as to not be needlessly "spinning my gears". This is where not having a pillion seat for an extra set of ears, is a big drawback. Maybe you can rig up a microphone?
The lubricant is far easier, so I'd start there.
The whine you hear from a spiral bevel gear set is the sound of the teeth engaging and disengaging, and the frequency will be proportional to the rpms, and generally much higher than the frequency coming from a drive shaft issue.
Spiral bevel gears will whine because:
- there is too much axial clearance,
- bearings are worn
- gears are worn
- lubrication is inadequate
Besides properly filling the rear drive housing with the correct lubricant, if you have any reason to think that the gearsets have been disassembled since they left the factory, they may have been reassembled incorrectly. Individual sets of gears are matched using different thickness shims. Here's the diagram for the rear angle gears: You can see that various different thicknesses of shims are available.
If, some mechanic was to rebuild a gearset using a one replacement gear, for example, the original shims would no longer be appropriate. Similarly, if there were two shims present, but one got left off in a reassembly, the clearance would be excessive. Gears want to be held in precise alignment, with some, but minimal axial clearance for each gear in the set. Same goes for the front set.
I'd want to be sure which end the whine was coming from, so as to not be needlessly "spinning my gears". This is where not having a pillion seat for an extra set of ears, is a big drawback. Maybe you can rig up a microphone?
The lubricant is far easier, so I'd start there.
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
