Hi everyone! I need a bit of help with a rebuild I'm gonna do on my 2014 400TRX.

But a little history: My first quad was a raced out 2000 400ex with awesome mods I bought off an older guy who ran her on the tracks. 428kit, stage 2 hot cam, racing motorcycle carb, holeshot tires, widened axle, racing headers and exhaust, reinforced frame, suspension was upgraded too. I say "racing" because I don't remember the brand names on the parts he used but almost nothing was stock on that beast. It was all beat to hell but still RIPPED. I had done a full breakdown and piston replacement on her after she slipped her cam chain and was so sure I got everything but i didn't notice the cylinder had tapped the valves after slipping the chain. After 3min or riding a valve broke loose into the compression chamber. That was the end of my old quad when I was in my teens. It was heartbreaking too, that quad was awesome. Beat to crap but so awesome....

I picked up a 2013 400x from the dealership with 0 hours on it. Since then I've ridden her hard(ish) and I believe she needs some TLC. I've had a ticking that's gotten worse over the months. I just did a new cam chain tensioner and an oil change and the noise vanished for a bit. It sounded like brand new again and I was so happy! But after a couple hours the tick came back and worse then ever so I believe my cam chain is stretched out too badly. I've also noticed she spits out smoke near the top of her RPM (hard rev in neutral produces it every time) so I believe she needs new rings as well. I wanna get this right so I've been watching a series of breakdown videos here:


I believe his videos will get me though this properly but I wanted to come here and get any info from you all that would be helpful in this rebuild. I don't wanna screw this up like I did last time. I'm 35 now and have 2 boys (6 and 2 years old) who love riding with me (putting around the field kinda stuff, nothing dangerous) and they miss riding about as much as I did when I broke the first one so long ago.

My biggest issue is parts. I wanna have everything I might need there when I do this rebuild. I think I've got most of them needed parts nailed down here in this list


1) Gasket kit for top end

2) Gasket for case (Right side for cam chain access)

3) Cylinder rings

4) Cam chain OEM CFR450 (alternative HD cam chain for a 400x DOES THIS STILL HOLD TRUE FOR MY 2013 400TRX?!?)

5) Cylinder O-ring (doesn't come with gasket kit for some reason)

6) Valve Stem seals

7) Cam chain guide

8) Take the Cylinder in to a machine shop to have it honed.


I've already got a new cam chain lifter so I shouldn't need to replace it

Am I missing anything? Any suggestions or tips that you all might have? Heck, any performance upgrades you could think of (that are not TOO expensive)? I need it all, Anything you guys could think of throw it at me.

Thank you for taking the time to read my Iliad of a post!