cush drive bushings

discussions specific to the 907IE
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jim

cush drive bushings

Post by jim »

Hello everyone,
This is my first post here, and I hope someone more knowledgable than me can help me out.
I have some excessive play between my sprocket carrier studs and the cush bushings on my '91-907. Neither look particularly worn, but there is noticeable movement between the two, and I am getting some snatchiness when I shift up and accelerate briskly. My chain and sprocket (two teeth larger)are almost new, and the stud nuts are tight. Would it more likely be the cush bushings that are worn, or the carrier studs? If it is the cush bushings where is the best place to get new ones? Any help is greatly appreciated.
Thanks,
James
User avatar
jomo
Posts: 127
Joined: Sun Jul 18, 2004 12:00 am
model: 906 Paso
year: 1989
Location: Australia

Post by jomo »

jim,

How many K's on the bike?

Are you sure your chain isn't too tight?

Put it on the centre stand and rotate the wheel forward a few turns, if it looks irregular, get back to us. Run it backwards, if it looks irregular, get back to us.

If you had twin carbs, I may have suggested something like carby balance....but I suppose that isn't going to happen with fuel injection!?
Brake late & brake hard,
jomo

Paso 906 Blue
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jim

Post by jim »

Thanks for the reply, jomo.

My bike's got 28K miles on it. No, the chain is almost new, properly adjusted and not too tight. The front and rear sprockets are almost new, also, being replaced at the same time as the chain. Nothing seems out of the ordinary other than the play between wheel and sprocket carrier, and the snatchiness definitely seems to be coming from the driveline.

Jim
Apex

Post by Apex »

If you have play between the drive hub and wheel, it is not worn cush drive bushings. That would result in the sprocket rotating slightly forward and back when the wheel is still--very unlikely given the thin rubber and its stiffness. When your rear wheel was last mounted were the spacers assembled properly? That is what I would check.

Jeff
jim

Post by jim »

Thanks Apex,
The play that I have between sprocket and wheel is not lateral, but linear. In other words, the sprocket does rotate slightly when the wheel is still. This is why I suspect either worn cush bushings or worn sprocket carrier studs, but as i said, the cush bushings nor the studs look particularly worn to me. I suppose, however, that it must be one or the other unless I'm overlooking something. What do you think?

Jim
Apex

Post by Apex »

Jim--

I will check my 907 to see if there is any play. I also have a spare wheel and sprocket assy off the bike so I can check it too. I don't know how many miles are on the spare but if it is tight we will know you have a wear issue.

Jeff
Apex

Post by Apex »

Well I finally checked both my bike and my spare wheel/sprocket and there is no play. The bike has 21,000 miles on it and the mileage on the spare is unknown, although it came off a well-worn bike. From the design of the cush drive, it's hard to see how you could get much play, but anything is possible. Did you check how well the sprocket is affixed to the carrier--I am sure you did but I thought I'd ask.

Jeff
krakan

Post by krakan »

Hi jim. My bike had the same problem with a slight slack between the sprocket carrier studs and the cush bushings. The
rubber didn´t look worn either. I first noticed the problem
when I was out riding last fall. I lokated a small slack (can one
call it that?? sorry not so familiar in written english. Must write more posts I think.) and I removed the rubber bushings then covered
them with hot glue from my glue gun and reinstalled them, I
wasn´t sure if it worked. I didn´t get a chance to ride again
until this spring but to my surprise no more slack!!! I read
about this fix in an old ex. of Motorcyklist and the dude had
the same problem on a zx kwak. It worked fine. Krakan
jim

Post by jim »

Thanks Apex for checking, and Krakan for your tip. I suppose my next step will be to take off the wheel and inspect things further. Should I need to remove the cush rubbers is there some trick to that? As I recall they looked like they were in there pretty snug with no obvious way to get them out. Does it require something like a bearing puller?
Thanks again for all the assistance.
Jim
Apex

Post by Apex »

Sorry Jim--I can't give you advise as to how to get them out, although I would like to know too. I am planning on having my rear wheel refinished and will need to get the rubbers out. I though of taking a cotter pin puller and cutting the point down so it fits down the hole and gives me something to use to pull, but I would also like to hear of the proper method.

Jeff
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