my friend has a 99 mxzx 440 and it doesnt seem to be very fast. It enages high and tachs out quickly at 8500.... how fast should it be? would it be anything to do with the clutching, or is there some other way to get it to move?

I owned one of these sleds brand new. The engine does engage high because it has to. It's a 440 and needs to rev. 8500 is exactly where you want it to run. There should be a green line on the tach and you want the needle to go there and stay there. What is not fast? They are geared low and do about 95 mph wound up tight. That is pretty good for a sno-cross 440! They are very impressive from 0 to 50. Can run with anything out of the hole. If you aren't seeing this type of performance then something is wrong. A friend of mine bought the same sled when I bought mine and they both ran about the same. Within 1 mph of each other.

well he was only going about 50-60mph and thats all it would do. it took off fast and climbed right to about 50 but then there was nothing left.

Take both clutches off and do some maintenance, while you have the clutches apart, check your springs. Primary springs last around 2 to 3 years(titanium,8 to 10 years), check bushings also. That sled should rock!

FZ700

gearing, jetting? Just a thought. FZ700 is right to.