1981 GS450 gear whine

[jagmandan]

Hi all,

I'm pretty sure I was hearing this gear whine last summer, but after taking the bike out after winter storage it's sounding quite loud. It's speed dependent, pulling the clutch does not really change it. Link to the video basically shows it all.

Is a noise like this indicative of a particular type of failure? Any advice on how to proceed greatly appreciated!

[Redman]

Seems speed related, not rpm related.
speedo seems smooth, but maybe try disconnecting the Speedo cable at the front wheel.

[Rich82GS750TZ]

Yes, as per Redman above, but if you do that, go ahead and remove the inner actual steel wound cable from the outer sheath or it’s likely to fall out on your test ride. If the noise goes away, take the speedo off and pot a few drops of 3 in 1 or sewing machine oil (something thin) into the spindle inlet. If you have a square bit (Robertson’s # 1 might be close to the same size, I don’t remember) put it in a drill and spin the speed with drill in reverse (this is important). Lube the inner cable before you re-insert it and fasten everything back together.

Same thing happen with the tach.

[Gorminrider]

That is noisy ! Does it do it coasting in neutral?

never had it myself but the speedo or tach as a source comes up a lot...you might want to see if anything reassembled under the engine/clutch/sprocket/spark advance covers is touching



You could also try spinning speedo with the cable connected by using a screw driver bit at the wheel end of the cable

for just the speedo, you can also use the sharp point of a nail to spin the speedo.. The point is square-cut. ....Likely need to cut the head off the nail and even improve it a little with a file before putting it in a drill to spin the disconnected speedo.

[jagmandan]

Thanks all for responses! I spun the speedo cable with my drill in reverse from the wheel end. Confirmed same noise, so I'll pull it and investigate/lube as suggested.

Very glad I asked. My thoughts went straight to issues in the engine case, hopefully this should be significantly easier. Sound was not at all clear in a helmet with engine noise mixed in. Now I know!

[jagmandan]

Hey all! Embarrassed to say it took this long (10 months!) but I finally pulled the speedo and lubed the inlet with some air tool oil. Did the tach as well. All quiet now. Many thanks!

[Grimly]

No problem. Thanks for letting us know, as it will help others.