Does anyone know if a 450r carb will fit on a 03 400ex and what else will you need to swap if anything?? Thanks for any input

 

I've read on here of people who have done it.
With a bigger carb you'll also want to put a high flow airfilter, like a Uni, maybe open the airbox lid up a bit and put a better pipe on it. Make sure your jetting is correct too.

 

You need to check out exriders.com and read about it. Very detailed and pictured to go along with it. This site sucks for anything more involved than changing your oil.

 

Than why are you on here?

 

I was just browsing and thought I would add to the discussion and give a suggestion to help the poster out. You my friend did not. Point proven as to why this site sucks. General flaming and nothing constructive added.

 

it will work i don't konw what mods you have but both my friends have stage 2 hot cams and a 440 bore kit and the 450 carb works well on both

 

Ya, because others are flaming... ANYWAY...

Yes it works. I did it with the help of THIS SITE. The best advantage was the slide style 450 carb is much easier on the thumb. The 450 carb is VERY hard to fit the stock boots. It's such a pain in the **** that if you plan on having it off very often at all I wouldn't do the mod unless you can get different boots on both sides. Especially the intake side, where the air box meets up. Not flexible at all.

 

Just go to exriders.com and send a pm to zrpilot. He custom makes the boots to use for the conversion to make it easier. I did this on my '08 400EX and it was not hard at all. I used the stock boots with a little massaging and a little heat. Went together great and performed very well. I didn't notice a difference in thumb throttle force though.

 

Really?!?! Man it was nite and day with me. Notice yours is a much newer EX than I had. Possibly yours just wasn't worn in like mine or maybe Honda went to a slide carb on newer EX's??

 

It is possible that mine wasn't worn out. I only had the stock carb on for about a week before I changed over to the 450r carb. I read somewhere that the carb for the '08 model was tweaked a little to ease push force. Not sure if it was true or not.