Just wondering if anybody has a similar setup on their 400 ex and what main jet they are using. Mine is stock except for a uni air filter, I have the K&N(Dynojet) Stage one and two jet kit. I will probably take the lid off or vent it. If anybody has a similar setup please let me know what jet you used.
Thanks

 

I have a DMC dual exhaust, K&N filter, 6-1" holes in the air box lid (really helped), and a 160 main. works great. I might try going up one more but i know the 165 is to big for it, so i might try a 162. But u can definately be safe with a 160 if your setup is similar to mine. good luck

 

hey madmark,
when you got the dmc was it a slip-on or complete system? also, if you get the slip-on can you convert to entire system after you build funds? thanks

Jera '00 400ex

 

Mr 400, someother post i did:
I just did all of this and I finally got it right. Got the DynoJet kit from the guys at DynoJet - its only 54dollars. compared to over 100 for the KN. I already had bought a KN filter - but replaced it with the UNI-because I was paranoid about dirt getting in thru the K&N. Now I have both, but will only use the K&N when i go to the desert only. Anyway - I have a FMF Powercore4 on my 400. Leave the idle jet alone, and the Main Jet is a 170. Got 6 holes in the airbox - the
UNI foam filter holes they sell at shops.
Before I bought the DynoJet - i had done this by buying the jets individually and removing the carb about 10 times trying different things - but I found it wasnt right. I had prob with the power between 4th and 5th.. it was bogging down... DynoJet includes a "thinner" needle and some special washer -- ??? looks very different than the stock... and from what ive been told-the Needle has more to do with the power than the Jet. Anyway, a buddy and I slapped the whole kit in about 1 hour - and went out to the street to try it out in the middle of the night -Runs like a champ!!! Go with DynoJet on your 400 - I was amazed at how nice it runs now. My friend has a Warrior and I can pass him up in low 4th gear - and so long after that. Another guy i raced last weekend - stock Banshee - open wide on a sandy river bed-once i got in front of him - he couldnt pass me.
Get the DynoJet.

 

Jeaner, I have the whole system, it's worth the extra money. I don't think u can buy the slip-on, and add the header pipe later because the complete system has two pipes all the way back to the baffle, and the stock header pipe has two coming out of the head and reduces down to one. I love the system, it beats my friends 400ex with a big gun..