Just bought a 95 Fourtrax 300 and the previous owner said the valves needed to be adjusted. *I haven't done it yet but let me pass it by you fellow owners. *When you start this up, unless you let it warm up for 5-10 minutes as soon as you hit the throttle it sputters and tries to stall. *It idles fine and when it warms up it doesn't do it as bad. *What do you think? *Valves? *Dirty carb?

I am not sure but I believe this quad has a electric carb heater in it like my Rancher and if this is the case that might be your prob.