back shift prob on nytro turbo

[Menace1]

dont think i have any rubbing i will look again

I am actually wondering what that might mean if the cogs are rubbing off a bit, my understanding is its from when the track is turning (say coming down a hill) without the primary engaged but still spinning, the belt rubs a bit on the shaft and its nothing to worry about. Any thoughts?

 

[Mcx Nytro]

Not sure what this means!

On the stock helix on the inside the hole near the center should be flush, they(yamaha leave about 1/4".

 

[Mcx Nytro]

One other thing to look at is how old is your track?? I had a viper and the lugs would fold over making the clutch shift up but I would have to let off to get it to backshift. Tis would happen no matter how tight I wound the secondary spring It would just drop rpm's if I didn't.

 

[zebiraross]

Val machines the shockwave AND one of the sheves of the secondary as well.

 

[BigFish BC]

One other thing to look at is how old is your track?? I had a viper and the lugs would fold over making the clutch shift up but I would have to let off to get it to backshift. Tis would happen no matter how tight I wound the secondary spring It would just drop rpm's if I didn't.

track has about a 1000km camo extreme 162 2.5 99% sure its the clutch sticking open & not back shifting. like i said it olny does it when wide open throttle ,then right off the throttle, then wide open,it will just hit the limiter like i have no drive at all get on & off again then away it goes. only time i have had a clutch do this befor, it was the slides on the primary that had gone but it felt differnt than this,this feels like the secondary.

 

[SPOOLED]

did you actually take the sec apart? i have had a cat green that was broken, it was snapped off about an inch before the lock tab. kinda hard to see for it still looked together.

 

[JSCC]

track has about a 1000km camo extreme 162 2.5 99% sure its the clutch sticking open & not back shifting. like i said it olny does it when wide open throttle ,then right off the throttle, then wide open,it will just hit the limiter like i have no drive at all get on & off again then away it goes. only time i have had a clutch do this befor, it was the slides on the primary that had gone but it felt differnt than this,this feels like the secondary.

So is there any drive when you get back on it, or is it coasting and revving up?
It dont make sense. We know that for what you are explaining to happen the belt is not grabbing either the primary or secondary. And if it were the primary, you would not loose drive when you back off it, it would bog from the lack of throttle. So it has to be secondary............
How much boost are you pushing?

 

[BigFish BC]

So is there any drive when you get back on it, or is it coasting and revving up?
It dont make sense. We know that for what you are explaining to happen the belt is not grabbing either the primary or secondary. And if it were the primary, you would not loose drive when you back off it, it would bog from the lack of throttle. So it has to be secondary............
How much boost are you pushing?

had it all apart today everything looks fine spring is fine buttons are fine it is the seconday thats slipping black marks right at the bottom of the clutch.it did it at 12lbs & now at 18lbs.there is no drive at all just reving it left o couple small marks on the clutch.

 

[Duke]

Geared too high?

 

[M5-]

Stupid question but how about a brand new belt?

M5

 

[JSCC]

had it all apart today everything looks fine spring is fine buttons are fine it is the seconday thats slipping black marks right at the bottom of the clutch.it did it at 12lbs & now at 18lbs.there is no drive at all just reving it left o couple small marks on the clutch.

Then I return to my previous guess. You either have a sacked spring or need a stiffer one....

 

[BigFish BC]

Stupid question but how about a brand new belt?

M5

ha ha yah have one in now but it wont quit raining here so i can try it out

 

[BigFish BC]

Then I return to my previous guess. You either have a sacked spring or need a stiffer one....

i will try a new one & see thanks guys.

 

[dexter]

make sure u wind it tighter this time i'm sure thats your problem

 

[NM]

make sure u wind it tighter this time i'm sure thats your problem

I think that would help. It almost sounds like alignment might be off a bit too. Make sure there are no small shims behind the clutch, just the one spacer. Maybe try just two small shims on the outside of the clutch. This is the same setup as we use and no problems. Also make sure you have the splines greased up so it can move around. I would also try pulling one of those slugs out and going to 86 gr weights for deep pow. The most we run on the Nytro's is 86 gr. 91 is more like a 20 lb boost drag race setup or spring snow setup. The Nytro's seem more sensitive to clutch weight than the Apex does. We are thinking Stewart next weekend...you in???????? I hear 4-5 ft of fresh this week and more coming.