hi i have a stock sprockets on my atv .
how do you find what rotio you need to get more increases maximum horsepower and torque?
would this work 14/42 or 14/40 or13/42??

I have a dmc pipe .

 

1 in front is egual to 3 in back

 

Speedy is correct, but changing sprockets doesn't increase horsepower. It makes your quad accelerate faster but you loose topend if you were geared at 13/42, 14/42 would be about the same as stock, and 14/40 would mean more top end, less acceleration.

Truthfully tho, 14/40 you may like. I heard you can barely tell a difference in accel, but you will find more top end. I'm sure you will loose some acceleration, but you won't feel much. 13/42 would be like overkill and 1st gear would be entirely useless.