Eton Viper 90R HELP !

[TC440EX]

Purchased a Viper 90R for my 8 year old. A friend of mine builds pipes for many manufacturers and used this as a mockup because of the reverse. The pipe is awesome as always and very easy to install. However the problem is we cannot seem to get the clutch correct. The guys at Eastside have tried to help but it is hard to do so far away. For some reason the bike will run good on hard pack but will not pull my 72lb son in the sand. We have tried jetting, filter, diff rollers , springs. Any help will be appreciated.

[LT80]

I need more info..
What's the pipe designed for? High rpm or low?
Have you tached the motor to see what rpm's it's running?
What rollers and springs have been tried and what difference did they make?
Torque spring also?

[TC440EX]

Pipe is built for mid to top. 5.0 , 5.4 and stock rollers. Red and green clutch springs. And Red large clutch spring. 95 and 105 jet. K& N filter. Every possible combination was used with negative results. Once it got going it did have better top end. Just will not move in the sand. It does fine stock.

[LT80]

OK,
If I'm getting this correct, the trouble is taking off.
Did you or could you try:: 4-4.5 rollers,red shoe springs, and the red torque spring.
Getting the roller weight light enough in the front is my guess.
lemme know.

[TC440EX]

Thanks. I will try this and let you know.

[Samson]

I'd try changing sprockets, if the rollers don't work. Cylinder kit helps bottom end a LOT or at the very least you might try a high compression head for a little extra power.

[mikeminyard]

So whatever happened with this?

[Kool Kidz]

LT 80's on the right track. Eliminate one problem at a time. Set the clutch right. Sounds as through your running a stock carb.?

1. The pipe has to be a question mark, not sure if your buddy got it right, maybe he did.

2. Stock carb could be giving you problems.

3. Set the clutch. It should, even with a stock cylinder be able to run this: Red or yellow rear torsion spring, red stall springs and 5.0 gram weights. Then leave it be.

4. Jetting, this is a question because I don't know what carb your using. If stock: You need a much larger jet for a main (typically for top end) but stock may just be too small. Raising the needle may help.

5. If pipes developing power in wrong power curve, head work may help a little.

Think we need more info on what mods you have done and if there are any other symtoms for this sick child.

[qwadfather]

Call me at (866)805-6330. It's toll free and It accepts messages 24/7. I'll get back with you and help you stop chaisin' your tail, lol! In the meantime ride safe, Ed and crew.

P.S, don't get mad if I try to sell ya Lucky 7 pipe built especially for the application. I'll yust be doin' my yob, man, lol!