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uncork 400EX
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Posted by: jjohnst03

I am going to pick up my 04 400EX from the dealer tomorrow. Is there anything I can do to uncork some power out of it without adding anything? I know with the 450r you can drill the t vent out and remove the exhaust baffle and open the airbox up a little to get a tad bit more power. What can you do with the EX without spending a whole lot of money?

Thanks

Posted by: muddy400EX

well, you could take the baffle out but it will sound worse than anything youve ever heard before. you could take your airbox lid off maybe, or drill holes in it. but w/o a pipe/jet/filter combo it wont do much

Posted by: nosliw

remove choke

Posted by: jjohnst03

quote:
Originally posted by muddy400EX
well, you could take the baffle out but it will sound worse than anything youve ever heard before. you could take your airbox lid off maybe, or drill holes in it. but w/o a pipe/jet/filter combo it wont do much

I wasnt expecting to get a whole lot out of it. I will probably just leave it alone until I can get a pipe.

What do you guys recomend? I dont mind it being louder than stock, but I dont want it to be annoyingly loud either.

Posted by: rsimmons_82

id definatly leave it alone... at least untill you get it broke in. hopefully, by then, you will have a little money saved up to do it right

Posted by: jjohnst03

Of course. The biggest part of break in will be done today. I am going to follow motomanusa or whatever his name is break in method.

Posted by: UglyMotha™

I took the cork outta mine a few weeks ago, I just gotta put her back together now

Posted by: igmif

Def remove the choke

Posted by: 2004exrider

completely stock 400s are harder than he11 to start with out the choke, if you do remove it put in a #42 pilot jet and you wont have a problem then.

Posted by: jjohnst03

Does the baffel just pull out or does it need to be cut out? I was thinking about pulling it out to see how it sounds, but if it has to be cut out then I wont bother with doing it. What size jets would need to be put in if I did take it out? The mean elevation in Arkansas is 650 feet. I live in southeast arkansas. About an hour from Greenville, MS.

edit: The choke doesnt seem to do much IMO anyway. When I turned it on to help warm up the bike the other day it just killed the motor. The first notch in the choke wouldnt kill it, but it didnt raise the idle speed either.

Posted by: 2004exrider

the baffle unbolts off it, your main jet is a keihin148 go to the dealership and get a couple sizes up shouldnt need no bigger than a k165 though, hope that helps u out.

Posted by: love4wheelin

where are you located in ohio?

Posted by: muddy400EX

quote:
Originally posted by jjohnst03
Does the baffel just pull out or does it need to be cut out? I was thinking about pulling it out to see how it sounds, but if it has to be cut out then I wont bother with doing it. What size jets would need to be put in if I did take it out? The mean elevation in Arkansas is 650 feet. I live in southeast arkansas. About an hour from Greenville, MS.

edit: The choke doesnt seem to do much IMO anyway. When I turned it on to help warm up the bike the other day it just killed the motor. The first notch in the choke wouldnt kill it, but it didnt raise the idle speed either.

well, was it cold out? if it was warm out then there is no point in using the choke. but when it gets cold out it is HARD to start, even with the choke