i have an 04 400ex.i am sending it to the shop to have a stage2 hot cam and stage2 moose jets with moose ignition.i have, but not put on yet 13t and 16t front sprocket.i need to know what rear sprocket i need that will be best to go with the atv? i want alot of torq and top end.

 

You aren't going to get more bottomend AND more topend from changing sprockets. You can only have one or the other no matter what combination of sprockets you are playing with.

 

i understand that you cant have both.i do know that i can have a fast bike with alot of power.i need to know what gears i should run with the 13t and the 16t. thanks

 

I run the 13/38 combo. I have plenty of bottom end and can still get to 61 in top gear going by GPS. I'm not sure about the 16t sprocket though. You can always just change the front and use the same rear. With the 16t your going loose some bottom end and gain a little top end. It won't pull hard on the top, but it'll go faster. The only way to gain torque and top speed would be to go into the engine and do a over bore, high compression, port/polish on the head. A stage 2 cam on stock engine is not going to give you what you're looking for.

 

so if i went with a 39t or 40t on the rear it isnt going to help me none

 

Going up 1 or 2 teeth on the rear is the same as dropping 1 on the front. It'll give some bottom end, but take away from the top end. The rule is one down on the front = two up in the rear. One up in the front = 2 down in the rear. What front/rear sprocket do you have now?

 

i am running 14t and stock 38t

 

Exactly how fast do you want to go on the top end? Your speed is limited first by gearing. If you have enough gear then you hit the rev limiter.

 

Try 13/37 This gears you lower for more bottom but also brings it back up a little for top end with the 37 tooth rear.
That's what I run on my 480

 

If you drop 1 on the front and 1 on the rear I don't think your stock chain will work without taking a link or 2 out.