Clutch HELP needed!

abumpa

abumpa

New member
Joined
Nov 14, 2008
Messages
95
Age
70
Location
Jackson Michigan
Having an over rev problem with a 2002 SXR 600.

Late last year on the last day of the last trip I noticed it was running up to 9000 to 9200 rpm. I knew this was to much so I took it to a local guy who I believe knows about clutches. He removed the primary and inspected it and said he could find nothing wrong with it. He said he would ride it first snow this year and try to determine what it is doing.

Well snow aint here in the lower part of MI yet, and I got a UP trip planned for Xmas so I put a new belt on it and went up to Cadillac and tried it out. Now she revs almost to 10,000!!!! Called the guy again and he wanted the secondary to look at and just today said that looked OK also, so we decided to rebuild the primary cause it appears the belt is riding low looking at the witness marks on the clutch.

Went to the local dealer to get a rebuild kit for the primary. They told me there are no rebuild kits available and ordering the individual parts would be over $300.00 A new complete clutch is about the same.

Anyway, I was wondering if the brain trust here could attempt to help me out with advice on what the problem could be, and where I can get reasonably priced replacement parts.

Below is a photo of the primary. It looks to me that the belt is riding low in the clutch as demonstrated by the heavier black rings perhaps caused by the new belt.

Thanks in advance….


DSC000033.JPG
 
I highly doubt that your clutches need to be rebuilt,my sled has nearly 9000 miles on the clutches and I've replaced one bushing in the secondary.These triples are very easy on clutches being so smooth.You need more weight in your primary clutch weights to get your rpm's down, thats the correct way to tune for rpm's in the primary.You need 4.5 a gram rivet put in your flyweights which would be heavier to bring rpm's down, but I'm not sure which hole, do a search if nobody chimes in.Also clean your clutch faces with some scotchbrite and then some hot soap and water also check your belt and clean if necessary.Sometimes there heavy mold release on those belts which is kinda greasy and can contribute to slippage which would make your rpm's even higher as you mentioned.
 
I should also mention that this is a stock setup. Last year as I recall the sled ran close to 100 MPH on a hard packed road. I do not recall what the rpms were.

Yesterday it only ran about 70mph at close to 10,000 rpm, but I didn't keep it there long. At 50 mph it was turning 7000 rpms.

Do you really think this is belt slippage? I am honestly asking as I have no idea.


While I got you guys here does anyone know the thread size for the outer hole on the clutch? Not the bolt that goes into the crank, but the outer threads that a clutch puller uses.
 
Last edited:
Your belt slipping is a small piece of the big picture.The biggest thing is adding heavier rivets in your primary clutch flyweights to get the rpm's down to 8500 rpm's.Overevving so severely is hard on things and I would'nt run it that way to long.When you get that right it will be faster and have better mileage too.
 
I was told by the original owner the sled was completely stock. He is an old guy like me and I believe that to be true.

Yes the belt in the photo is a new Yamaha belt.

Also when I first rode the sled last year it did not over rev like it does now, but I do not recall what the top rpms were.

My guy is working double shifts at his real job and has loaned out his clutch puller so today I an going to try to find a bolt to make one. I don't know how to answer the question about what is my set up...sorry.
 
Last edited:
abumpa said:
Late last year on the last day of the last trip I noticed it was running up to 9000 to 9200 rpm.
Click to expand...
Ok did it do this when you first got the sled???,was anything done to the primary??
 
Nothing was done to the primary since I have owned it.

On the last day of my 2nd trip last year I noticed the high RPMs and had the clutch looked at when I got back.

As dumb as it sounds I do not recall the RPMs the sled ran at up until then, but obviously it did not cause me concern.
 
Last edited:
Ok try this... put in 4.5 rivet inner & a 3.6 rivet outer in your stock weights with a 51/43 helix. should help that over rev. and giver a good performance gain.
 
You must log in or register to reply here.


Back
Top