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Re: clutch graunch

Posted: Tue May 29, 2012 11:00 pm
by DaveBBR
I had a VW that did something like that after a rollover. There was gravel in the clutch housing.

Hi everybody. Its nice to be back.

Dave

Re: clutch graunch

Posted: Tue May 29, 2012 11:07 pm
by Chuey
Duane Ausherman wrote:Pulling the clutch lever is unrelated to the splines. You are grabbing at straws on this one. Did you check the input shaft end play before installing the box?

Always do that, as it is easy and may save a swap later on.
The input shaft is the shaft that sticks out of the transmission and has the spines that the clutch disc rides on, right? How much play is it supposed to have? No. I have never checked that. The transmission came from a bike that had 34,000 miles on it.

I think I understand you to be saying that the clutch doesn't move in and out on the splines but is free to float on them when the clutch is disengaged. Right?

Chuey.......trying for a better understanding of this.

Re: clutch graunch

Posted: Tue May 29, 2012 11:09 pm
by Chuey
This is such a problem for me because I have the motorcycle lift disguised as a frame jig at this time. In other words, I can't use it for up fixing my bikes and maintaining them. Those stands spoil the heck out of you. Otherwise, I'd have parked that puppy on the stand and the tranny would be sitting on the ground by now.

Chuey

Re: Graunch

Posted: Wed May 30, 2012 12:19 am
by Major Softie
Steve in Golden wrote:
Kurt in S.A. wrote:Can someone define "graunch"?
I wondered about that too.

1. Graunch

To damage something by using excessive force, often with the use of an incongruous implement

"I can't seem to close this lid, it looks like someone's tried to graunch the fucker open"

http://www.urbandictionary.com/define.php?term=graunch

I think I like "incongruous implement" even better than "graunch."

Re: clutch graunch

Posted: Wed May 30, 2012 4:56 am
by chasbmw
I had lots of shifting problems on my 82, they were resolved by

1: replacing the clutch pushrod and all associated bits. Richard Difazio was of the view that it was possible that over the years culmalative wear had built up.

2: adjusting the clutch very carefully using the 201mm method.

I think that these bikes are really sensitive to clutch adjustment....... Simple and cheap.

Re: clutch graunch

Posted: Mon Jun 04, 2012 12:59 pm
by Chuey
I was out looking at the bike and grabbed the clutch lever and squeezed it. It is smooth as silk.

It occurred to me that it is only when the bike is hot that the clutch engagement gets rough. I should make it clear that it is not the actual engaging of the clutch but the release of the clutch that is rough. In other words, when the clutch engages, it is smooth and positive on the flywheel, as it were. It is within the "throw out bearing" part of the bike that the problem lies.

What part of that system, (rod and bearing) could get rough when it is warm?

Chuey

Re: clutch graunch

Posted: Mon Jun 04, 2012 1:08 pm
by Deleted User 62
Chuey, you can pull the throwout bearing and associated bits for inspection and cleaning without removing the transmission. It could be the bearing just needs some grease, or a bit of grit got past the rubber boot.

Re: clutch graunch

Posted: Mon Jun 04, 2012 5:32 pm
by Duane Ausherman
The usual symptom when hot is that it will grab, no matter how careful you are with the lever. You have never mentioned anything like that, so it is something else.

The diaphragm plate can pack up with dirt and not release. One can clean it and get the dust out.

Re: clutch graunch

Posted: Mon Jun 04, 2012 8:28 pm
by Chuey
Duane Ausherman wrote:The usual symptom when hot is that it will grab, no matter how careful you are with the lever. You have never mentioned anything like that, so it is something else.

The diaphragm plate can pack up with dirt and not release. One can clean it and get the dust out.
I can tell it is not in the clutch engagement between the pressure plate, friction disc, and clutch carrier. I have isolated it to the points between the clutch release lever and the rod/bearing which act as a throwout bearing. They were replaced at the time of installation and work just great when cold. Since rebuilding the bike, it has about five hundred miles on it so it is not dirt.

I think I'll take out the parts and see if there's anything visible. That is, the parts suggested by Timo.

Chuey

Re: clutch graunch

Posted: Wed Jun 06, 2012 4:52 am
by chasbmw
Cheuy,

You have the later throw out bearing with the plastic outer?

This can swell with heat and cause problems, solution is to reduce the diameter a bit, using sandpaper.