Hello!

[Mike594]

Hey all, I did some searching on the net and found that this forum is probably gonna be the most helpful to me. I just recently bought a 2003 400ex and was wondering what are the best websites for aftermarket parts. Also, I want to get a jet kit for it, but only want something like 1 - 2 notches up from the OEM jets, like 40 or 42 pilot. (I believe stock is 38 correct? As the quad is not really modded at all at this point in time.) Which jet kit do you guys think the best one to go with is? Any help would be much appreciated. I look forward to posting and talking to you all. Thanks!

[ae13291]

if u are mostly stock bump to a 40 pilot not a 42 like some will say, also move the main jet up to 150. u can get single jets form your local atv shops.

[sprayedgt]

Welcome to the site. I know a lot of people that use rockymountainatv.com. Just go ahead and get the jets you need for the mods you make from your Honda dealers. A jet kit is way over priced for just the 1 or 2 you'll need. Use Keihin jets whenever possible. Jetting a stock engine won't really do anything for performance. But the 42 pilot will make the cold starting issues disappear.

[Mike594]

Well thats all im really trying to do for now. Just trying to help eliminate teh cold weather issues, seeing how I live in NJ, it gets pretty cold here in the winter. Was only 26 yesterday. Also, what oil should I use for an oil change. I've heard anywhere from 10w30 to 20w50. Please shed some light on that, lol. Do you think its ok to use synthetic? Thanks guys.

[F150 Rider]

Welcome Aboard!! I use 10w30 motorcycle oil for wet clutches in mine.

[sprayedgt]

I use Mobil 1 Racing 4T 10w40 in mine.

[Mike594]

Is automotive oil ok to use? I work at a NAPA so I have access to pretty much any kind of oil out there.

[lilyamaharacer4]

I would stay away from the automotive oils because many have friction adders. And not to mention these are wet clutches. Run motorcycle oil and forget about it.

[Mike594]

Thanks all, for the info!