400ex 440kit

hi i have a 2000 400ex if i get a 440 big bore kit do i have to beef up the jet too?

You will need to do jetting work yes, and you might also want to run an exhaust system. Be warned, as soon as you put a big bore kit in it, the engines reliability drops... My buddy has a 440 kit in his bike, and it's a beast to start, especially on cold days. It's jetted properly too.

It also has a Curtis Sparks Full with a jet kit. But I was also told that if you have over than 10.5:1 compression you have to run cam2?

If it genuinely needs a rebuild, I would go 416 before I went 440.

If you are just looking for more performance with the 440, reliability will be an issue!

thanks but also. if your comp is higher than 10.5:1 you have to run CAM2? s this true?

thanks but also. if your comp is higher than 10.5:1 you have to run CAM2? s this true?

no but if you have a smaller one your motor would be more low end

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