Interesting sound from the tranny

[chris in va]

This could be bad, could be nothing.

200 miles ago I started getting this dry 'hissing' sound from the transmission whenever I give it positive load.  Let off the gas, noise goes away.  Speed of engine doesn't seem to give it a different pitch, nor does bike speed.  Clutch doesn't slip any, acts pretty much normal.

On a side note the clutch lever has really gotten harder to pull, or I'm just getting weaker...?

I may be selling the bike soon so need to be sure this isn't something bad.  It has 10,500 miles on it.

[ajgs500]

take the gag out.....  i bet u could understand shim better

[starwalt]

...200 miles ago I started getting this dry 'hissing' sound from the transmission...

Inspite of aj...(Bad! Bad!  )

I assume your oil level is OK, so are you certain this isn't a vacuum hiss?

If it were though, I doubt your engine would run well and you don't seem to be saying anything along the lines of "My engine runs rough when..."

It still seems to me to be a vacuum leak issue. Can you isolate the location positively as the transmission? Any particular gear or all gears?

When you say the clutch lever is harder to pull in...it could be that the cable needs lubrication/cleaning. If this bike spends nights outside, it only takes a little moisture to start the corrosion process. We also don't know the year and history of this GS.

[DerekNC]

I read on the older GS model forum that it's the clutch causing that  noise. I'm pretty sure my bike is doing what you describe as well, kind of like a "metal brushing" noise. Mine only does it intermittently.   

[chris in va]

When I say 'hissing', it's not a vacuum leak but a dry sound similar to it, only when I get on the gas. 

Garage kept, 94 with 10,200 miles.  I'm the second owner having put 1000 miles on it in 3 months.  Previous owner rode it as a commuter bike into DC and really didn't take very good care of it.  Oil level is good, fresh change last week.

I could definitely see it being some sort of bushing, that's why I'm concerned.

PS...AJ, I have no idea what you're talking about.

[Gisser]

PS...AJ, I have no idea what you're talking about.

  Sometimes it helps to know the author's posting history.  Replace tranny with transexual in your subject line then enjoy the wit that went into setting you up in the punchline.    ....if you haven't already.

Shim!  You learn something new everyday.    This also ties in to both trannies (mechanical & human) but a touch too clever to be intentional?

I could definitely see it being some sort of bushing, that's why I'm concerned.

Hard to diagnose over the Internet.  More isolation needed:  Does it hiss in neutral on the throttle?  With the clutch in?  

[ajgs500]

PS...AJ, I have no idea what you're talking about.

  Sometimes it helps to know the author's posting history.  Replace tranny with transexual in your subject line then enjoy the wit that went into setting you up in the punchline.    ....if you haven't already.

Shim!  You learn something new everyday.    This also ties in to both trannies (mechanical & human) but a touch too clever to be intentional?

Ha ha nope that was definately intentional!!!!!

[chris in va]

No, the sound is only when I give it gas in gear, putting load on the chain.  I'd take it in to the stealership but they're booked for over a week.

[starwalt]

Could it be something like a dragging brake pad?

That would be a dry hissing sound. Have you checked to see if the rear brake pads are nearly evenly worn?

Have you ever checked them? I've seen TWO sets of rear pads totally worn through, metal plates sandwiching the rotor, that were on bikes being ridden!

The fact you mentioned the previous owner didn't take proper care would fit right into the pad theory. Also, new riders tend to use the rear brake way too much. I guess it is a hold-over from the bicycle days.

You can always put her up on the center stand, put it in neutral, take the load off the rear wheel (sand bags, friend, etc. on the handle bar/front wheel) and determine if the rear spins fairly freely. Minor pad drag is normal, but you should be able to rotate the tire/rim assembly while in neutral.

[chris in va]

Update.

I decided to check my chain's condition, taking off the sprocket cover.  Holy cow.  O-rings everywhere!  Dozens of them, packed in dirt and grease probably for a long time.  Half the chain's rings were GONE.

So I changed the chain, no more noise.  Plus I have a 15t sprocket on order which should help with the low end grunt. 

Thanks for all the advice, glad it wasn't something serious.  The previous owner was a real idiot.

[Gisser]

Update.
I decided to check my chain's condition, taking off the sprocket cover.  Holy cow.  O-rings everywhere!  Dozens of them, packed in dirt and grease probably for a long time.  Half the chain's rings were GONE.

Sticky chain-lube has been known to cause chains to throw o-rings.  Something to consider when choosing lube.