I have a stock carb left over after installing a 39mm FCR carb on my 400EX, and was wondering if anyone here has installed a stock 400EX carb on a 300EX? If so, does it just bolt on or does it require modification? Can you use the stock throttle cable? What jetting changes were necessary?

 

I saw a webpage that had this, but I can't remember which one it was. Might have been exriders.com I dunno

 

it can be done, my freind has a 390 kit on his 300ex but the gas tank needs to be raise for clearence so does the front plastic
http://y42.photos.yahoo.com/bc/quad0...src=ph&.view=t
quad041

 

The 400EX carb goes on without any alterations. The stock 300EX throttle & throttle cable works great with this setup also. My 300EX's have a Honda 350X three wheeler airboot on them, which is a direct replacement of the 300EX airboot. A 350X airboot (the boot between the carb and airbox) is slightly larger than the stock 300EX boot. As for altering the tank and front plastic for it to fit, I have had no problems.
Rick

 

I have a 400ex carb and a 350x airboot on my 300 also, it bolted right up with no problems. There is no need for altering gas tank or plastic.

 

Same here, 400EX carb and 350X airboot on a 330EX without any modifications. (thanks XC426 )