82 GS1100G question....

[Guest]

And this may be a trait of all the shafties, but this is the first i've owned so i dunno.

In between 3000-4000 RPM or so, in 3rd and 4th gear, throttle relaxed but not closed (maybe 1/8th to 1/4 throttle...cruising possition) I get a hum. Its very audiable, even with my helmet on, and wind. Its a whine, but not a HIGH pitched whine, and not a low pitched whine/rumble. There seems to be no vibration in the bars associated with it, but it seems to sound, as best as i can tell by leaning my head close to the motor (keep in mind im in motion listening for this) as if its coming from either the tranny, OR the secondary gears. I obviously cant really tell from where exactly cos i cant get my head close enough. It doesnt really do it in the other gears, maybe a lil in fifth but generally in fifth im above this RPM range most of the time, and going fast enough the wind roar may drown it out a bit. Again, it doesnt seem as if its causing the bike to run foul in anyway...YET, and i wasnt sure if this is a pretty common sound on these bikes. Also, the rubber blocks that go between the vertical head fins are gone/dried out, so I was thinking maybe it was resonation causing them to hum. Dunno...Anyone else ever hear/notice this? Is it gear lash off, causing the whine? Should I be overly concearned about it???


EDIT: Oh also I will add that when increasing throttle input, it seems to make it go away....odd...

[bwringer]

Resonance from the engine fins would be a high-pitched ringing, so don't worry about that. Pick the hardened remains of those little rubber blocks out without fear -- I've never bothered to replace these or worry about them in the least, and I've never heard any odd noises either.


Back to the mysterious whine...

There's approximately a 99% chance this is nothing to fuss about at all. Maybe your ear plugs lost their loft?


To eliminate that last 1% of doubt, there are a few things you can check:

1) Drain/replace the bevel gear (meaning the bevel gears at the rear of the engine) oil and make sure there aren't any gobs of metal shavings in there.

2) Peel the u-joint boot back and wiggle the stuff you find in there to see if there's any excess play in the bevel gears or bearings. Problems here are rare, but not unknown, and any sloppiness should be pretty obvious.

3) Check the gears in the rear hub in much the same manner -- drain and examine the oil, and hold the u-joint stationary with a screwdriver or something and wiggle the rear wheel back and forth. Problems here are very rare.

Someone else will likely have a few more ideas...

[TheCafeKid]

Resonance from the engine fins would be a high-pitched ringing, so don't worry about that. Pick the hardened remains of those little rubber blocks out without fear -- I've never bothered to replace these or worry about them in the least, and I've never heard any odd noises either.


Back to the mysterious whine...

There's approximately a 99% chance this is nothing to fuss about at all. Maybe your ear plugs lost their loft?


To eliminate that last 1% of doubt, there are a few things you can check:

1) Drain/replace the bevel gear (meaning the bevel gears at the rear of the engine) oil and make sure there aren't any gobs of metal shavings in there.

2) Peel the u-joint boot back and wiggle the stuff you find in there to see if there's any excess play in the bevel gears or bearings. Problems here are rare, but not unknown, and any sloppiness should be pretty obvious.

3) Check the gears in the rear hub in much the same manner -- drain and examine the oil, and hold the u-joint stationary with a screwdriver or something and wiggle the rear wheel back and forth. Problems here are very rare.

Someone else will likely have a few more ideas...

Thanks Brian, I will give those things a poke and a prodding, and see what i find. I do THINK that i need perhaps to check my Ujoint anyway, as occasionally i feel it snap/clunk when you let the clutch out quick. Mayhaps this would follow along with the sound, but ive no real idea. So no real chance that it would tranny issues either? I dont think so, as I said i have yet to associate the sound with running, shifting issues.

[bwringer]

Have you replaced the driven spline in the rear wheel yet?

This will sometimes start to give you some slop and clunking right before it goes kerblooey. And yours WILL go kablooey if it's still original.

[TheCafeKid]

Actually, the rear spline is inside an 81 rear wheel, which is on the bike now thanks to Steve loaning it to me when the stocker DID go kablooey. Took the wheel with it unfortunately. Nadda wrong with the pumpkin tho thankfully. And the hub gear in the 81 wheel is purty, and coated in Honda Molly60 now, so it should be okey dokey.

[bwringer]

Excellent.

It's also very rare (I've never heard of it happening at all, actually) for the U-joint in a GS driveshaft to get sloppy or wear out. But if the flange it's bolted to moves around in an unseemly manner, then there's a problem in the bevel gear and/or their bearings.

[TheCafeKid]

Well i lucked into an NOS still sealed in the box from Zook Bevel gear set, (fleabay, got it for 10 bucks! one of those just in case things i picked up) and I REALLY REALLY hope i dont find slop back there, cos the thought of having to take it down for the summer, and on top of that having to split the cases is more than i can bare. I think i would flip my lid if i had to shut it down

[bwringer]

If it comes to that, you don't have to split the cases to replace the bevel gears.

You do have to loosen the case bolts in the general area.

And you'll also want to put new o-rings on them, and make sure you pay careful attention to the "TOP" markings.

[nathan12]

my 1100 does that and it is because the rubber spacers between the frame and gas tank have worn away. actually it USED to do that, fixed it the other day...just an idea.