Has anybody attemted to use the stock FCR carb from a CRF450r on thier 400ex, its a full race style carb, but has a choke for cold weather riding. Honda has a huge selection of needles to choose from so I'm sure it could be done well. Who's tried this or whi is it a bad idea?

 

Sounds like a smart deal to me. Do you know the inlet/outlet sizes? I have to take my stock carb off to put in a new jet whenever I get it[img]i/expressions/face-icon-small-disgusted.gif[/img] and I could measure the size of the stock carb. Measure to the outside of the flanges. If it's bigger on the inside, and the same outside diameter, I'd be ordering me a new carb, or finding one off Ebay[img]i/expressions/face-icon-small-wink.gif[/img] I wonder how the throttle would hook up? FCR is a kehin carb, right? I don't see how it could be too much bigger then the carb on a 400EX, because the bikes have less room to put a carb in anyway-unless it is an oval bore. Then we're screwed unless someone makes intake manifolds to adapt to the EX.

 

The physical size is not a problem. I had installed the fcr before so I know space isn't a problem, Throtle hook-up shouldn't be to big a problem...I'll have to pull a carb off a new bike(CRF450) and measure it out.

 

well, while we're on the subject of carbs, and since I'm not at home to measure my stock 400EX carb, what about using a carb off a XR400? I know that the cam from the XR really wakes up the EX motor, and now I'm wondering about the carb. Honda specifies a different carb for the XR. Anybody ever done it, or seen it?

 

I think you could make the stocker work as good as the xr400's, but not nearly like the fcr does...this is for a 440+ cc EX with high compresion and a large cam (HRC or Stage II)