I have a so called friend that just bought a PROX 700 04, because he could get the payments cheaper than on arctic cats program. Anyway, (I drive an F7), he is wanting me to help him on a better clutch setup/ gear setup. One thing to keep in mind, is that the guy weighs about 300, give or take 20 pounds. He's kinda large. Any suggestions would be greatly appreciated. Thanks. J.

Gear it to 24/42, jet the mains down to 420, go to an almond/red primary spring, red/blue secondary spring. See what it rpm's with those changes, and then he may be able to go to heavier weights, or a steeper helix.

Thanks pockets. If we don't here any other replies, we'll try this. Not that I don't trust you, but just kinda gettin an idea. thanks.

What is the optimum RPM for this sled? What gears come stock? Would this recommended gear change require a chain change?

Comes with 25/41, you can use the stock chain. You want 78-8000 rpm. For his weights, you need to gear down to that ratio, maybe even lower.

If he's 300 lbs I would go a little lower yet, as Pockets alluded to. 23/42 (1.83) still works with the stock chain I believe.

I concur with Pockets post.

My 03 PROX 700 works well with a almond/red primary spring, red/blue secondary spring. I am running 64 weights and a 70/42 helix also which pulls really well but i am 185lbs and run on hardpack @ cold temps. He is big for the 700 and probably can't run that heavy clutching. Definitely run 420 mains.

Use the 2 spring suggestions for sure, you might get away with either 64 primary weights OR the 70/42 helix but likely not both.