2003 400ex

[Cowboyboots]

I just bought this 2003 honda 400ex a couple of weeks ago and have been having a ball on it. I took it out to some dunes near here and it did good for the tires it has, just bought paddles last week. I bought the quad with probably 20 hours on it and it had not really been rode at all. It came with a big guns exhaust slip on, rejetted carb, and a uni intake. The bike can hold its ground but my friend has a 450 and i want to be able to keep up with him. I am into diesels big tiime and actually going to school right now for them. I dont know much about quads or bikes and was hoping you guys could point me in the right direction. What all do i need to do to keep up with him?

[01boneless]

welcome to the atv world lol youl love the 400ex but as far as keeping up a simple mod would be to change your gearing .if you want to crack the motor open put in a cam stage 1 or 2 and mabey a high comp piston a good mod is to run premium gas

[Cowboyboots]

i have ran about 3 tanks of fuel through it already, all 91. fresh oil and filter change.