Can a 500 rpm overrev up top be caused by a worn belt???

[RSVECTORFREAK]

My vector with ulmer clutch kit has developed an overrev up top. When i installed the kit it was hitting right around 8600 up top and after 2000 miles it now is climbing to 9100+. A friend mentioned maybe the belt was getting worn after 2000 miles since I put a new one on with the kit. I compared it to my spare belt as far as thickness and wearing but they were basically identical. Not sure if my spare was a new belt or not! I am toying with the idea of adding a gram of weight to the tip of my supertips or trying a new belt any suggestions???? The belt is riding slightly above the secondary as per spec and the primary when marked with a marker seems to be in spec also. Clutch springs were also new at install of kit and buttons looked good in the secondary. I am running 21/38 gearing with an 80 degree twist on the helix.

 

[baggs66]

Yes I would try a new belt first if it was OK before make sure you clean the belt and clutchs and check for binding of the bushings and it should come back. That or you started to make lot more power lol

 

[dubla92]

Replace the belt! 2000 miles on a belt on a vector or nytro is time to replace the belt. Clean the clutches and replace the belt. They get hard and slip like crazy after 1500 miles. I replace the belt on my nytro every 2000kms to keep the RPM in check. Not to mention that the slipping of the belt is very hard on the sheaves.

 

[dan wilson]

I can only get 1300-1500 mile's on stock belt's on our 06 vector and 06 nytro,we blow them up(cap come's off)they are stock yamaha belt's,I just buy four new one's every year,just bought at nelson's all four for 190.00 with tax.

 

[kinger]

This is the yamaha OEM 8DN belts? Jeepers they have the reputation of lasting forever. I got over 4000 miles on mine with a supercharged 250hp apex!

 

[Riceburner]

This is the yamaha OEM 8DN belts? Jeepers they have the reputation of lasting forever. I got over 4000 miles on mine with a supercharged 250hp apex!

X 2.

3600 miles on my Stocker still very good.

6800 miles on my former 200 HP SC Apex GT before she blew. [ Mostly before it was Supercharged.]

Mind you it wasn't pretty. The belt blew at well over 110 MPH while I was testing it for a buddy who bought the sled from me. He should have changed it sooner I guess.

 

[natedawgedog]

How many miles on the snowmachine itself? is it possible that your engine is finaly broken in and is making more power, I know when I got above 2000 miles on my nytro xtx it was making a lil' bit more power. I dont use the 8dn belts (to hard imo) but I switched out a new belt and had no change in performance, so I added a gram of weight to the tip of my supertip weights and that brought them back down to the sweet spot.

 

[Irv]

Is there not a newer updated belt to the 8DN? Is it now now a 8DN-01 or something like that?

I have yet to purchase a new belt but plan on it this year.
Fwiw, they are about $120+ for a new belt up here!

P.S. Have you washed your belt and lightly scuffed your sheaves lately, plus cleaned your clutch?

 

[thor452]

wow I get mine $49.00 USD at the snow show each year

 

[thor452]

the only update im aware of is the one a few years back for the phazer w/reverse. all others are the same yamaha belt.