Alternator dampers GSF/GSX etc

[fbody_mike]

Hopefully someone here has messed with the external alternators on Bandits, Katanas, GSXRs so on. I got a knocking noise at low rpms when cold and dragging the clutch. I replaced the chain and sprockets with a small change in the noise, when the noise is heard and you put your hand on the alternator you can feel the vibration in synch with the noise. Its not loud, just annoying, especially because I run a stock exhaust. Check out the video below and see if this amount of play in the gear is normal.

https://www.youtube.com/watch?v=-ukC9qM877I&feature=youtu.be

[fastbysuzuki]

Not sure about the play, I had a car sometime ago that had an annoying chink/ noise at tick over it turned out to be two gears that ran together catching up on each other,fix was raising the tick over speed a little.

[tom203]

I got one of this style alternator....I just checked, no play. The nut that holds the gear on is staked to shaft...maybe yours came loose and is letting the bevel gear wander.

[fbody_mike]

I checked the nut and it is tight and staked still. I actually ordered replacement dampers already, but I did not want to disturb the factory staking if that play was normal. Thanks for checking.

[hjfisk]

I am no sure but I believe Suzuki knew this was a problem , because the later year bikes were set up different, the did not have that big gear , they splined into a smaller gear that was about the size of a wheel bearing. The slides were mounted in rubber. I know this because my 98 GSXR 1100 tore one up one year when I went to Fla. for bike week. Happened the first day there. I had to overnight the part in from Suzuki

[fbody_mike]

Actually if it is the alternator, it was probably caused by the "lean sneeze" backfire through the intake this bike suffered with until I retuned it. Digging up what I could about this noise and the alternator I found many times where the nut actually backed off completely on some older bandits but the clutch kept the gear from coming off the shaft.

[fbody_mike]

Replaced the dampers in the alternator and the noise is gone. The old rubbers were worn and starting to crack. Aft I installed the new ones there was no play in the drive gear anymore. Job done.

[fbody_mike]

Well the noise I was fighting came back last week. The alternator is quieter now, no more rattling noise, but the main noise I was after was more of a rod knock noise. So it got bad enough this weekend that it did it when warm too and I got a chance to chase it with my mechanics stethoscope. Turns out it is the petcock. The thing has a slow vacuum leak and when at low rpm (below idle) it knocks like a loose wrist pin. I set it to prime and blocked the vacuum line, noise is gone. Who would of thunk it ??

[Grimly]

Well the noise I was fighting came back last week. The alternator is quieter now, no more rattling noise, but the main noise I was after was more of a rod knock noise. So it got bad enough this weekend that it did it when warm too and I got a chance to chase it with my mechanics stethoscope. Turns out it is the petcock. The thing has a slow vacuum leak and when at low rpm (below idle) it knocks like a loose wrist pin. I set it to prime and blocked the vacuum line, noise is gone. Who would of thunk it ??

That's an oddball one, indeed.

[steve murdoch]

Well the noise I was fighting came back last week. The alternator is quieter now, no more rattling noise, but the main noise I was after was more of a rod knock noise. So it got bad enough this weekend that it did it when warm too and I got a chance to chase it with my mechanics stethoscope. Turns out it is the petcock. The thing has a slow vacuum leak and when at low rpm (below idle) it knocks like a loose wrist pin. I set it to prime and blocked the vacuum line, noise is gone. Who would of thunk it ??

Excellent detective work!
Certainly a new one for me as well.