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Blown Belt


I took 3 flat washers and sanded one edge flat so they would fit under the helix. I then put them on the surface grinder and took them all down to 0.06 so they were identical. They are placed on the 3 posts underneath the holes in the helix. You have to make sure the flat spot stays to the inside when tightening the helix so they fit properly under the helix. I also used some blue loctite on the post threads. With the shims it's really close getting a thread to protrude through the nylon portion of the flange nuts.
 
I have pictures of my washers from my Viper I will try downsize to post later
 
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Not sure I follow. I thought the 8dn was a softer belt compared to 8jp? The 8dn wears into primary sheaves? First Yamaha and learning
Yes 8dn wears into sheaves. Always been that way but these 3's with no gear reduction are worse because of stupid clutch rpm. Even back in 98 I did not run 8dn on SRX mostly for that reason.
 
Sounds like some progress is happening which is good. My question is where is Yamaha in all this? You can't tell me they haven't heard about the belt breaking/blowing issue. Do we now leave it all up to the speed shops?

Another thing I find ironic.... In the beginning when everyone finally saw the preview of these machines the question was.....do I get the T-Cat or do I get the Sidewinder? I saw countless people say the SW because of Yamaha's quality of their clutches. Too many Cat's with belt blowing issues.

Talk about a slap in the face! :o|
 
Sounds like some progress is happening which is good. My question is where is Yamaha in all this? You can't tell me they haven't heard about the belt breaking/blowing issue. Do we now leave it all up to the speed shops?

Another thing I find ironic.... In the beginning when everyone finally saw the preview of these machines the question was.....do I get the T-Cat or do I get the Sidewinder? I saw countless people say the SW because of Yamaha's quality of their clutches. Too many Cat's with belt blowing issues.

Talk about a slap in the face! :o|


Yamaha won't do anything unless a lot of people are breaking/blowing belts and the dealers are notified. Since this site is not a dealership....it doesn't go directly to Yamaha and Yamaha will probably not know about the belt issue. Secondly is that Yamaha will not call clutches back if you can't do 110mph....

This is why we are all here.... to help one another out.
 
Yes 8dn wears into sheaves. Always been that way but these 3's with no gear reduction are worse because of stupid clutch rpm. Even back in 98 I did not run 8dn on SRX mostly for that reason.

Are you talking above 9,000 rpm's?

I ran the 8DN on my 2002 2 stroke Viper for 9,400 miles and had little or no wear. That was a stock motor and exhaust taching around 8600. Now on the current 2007 Attak GT that I bought used from Pat's the sled already had 12,000 miles on it. The original owner was an easy rider that drove around 50 mph. This clutch was grooved right around the 50 mph mark on the primary. I had the faces re-machined to get rid of it before I clutched it. My tach runs 10,800 with my setup but obviously this is gear reduced to the clutch.
 
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