rev box???

Well guys... i Have a question.

what do you guys think of putting a rev box on an xr650r ??? Now ive always thought they were pointless because if the engine was going to continue making power higher in the rpm range then the manufacturer would let it go higher{ to a degree } But now i have a fmf powercore 4 and a stage 2 hot cam and im wondering if it would benefit from it now .

Any help would be greatly appreciated

Your friend and mine ....Scott

I am sure that there is some power there. Honda really derates the engines. That is one reason for the longevity. The air intake is choked off, the exhaust is corked, and the revs are limited. If you open up the intake and exhaust there should be some more power at high revs. A cam can really help here. The downside is accelerated wear at the higher rpms. Wear rates are not linear they are exponential. It is a power law with an exponent a little over 2.

Very good post, cleonard. My beliefs with the big thumpers are that they will last forever if set up for the enormous torque they are capable of in the lower rpm range. A high revving thumper just does not have the durability, example= any new mx 4 stroke. Its why they always need top ends. Yes there are gains to be had with the ignition curve, however if you want a durable bike, mods thats improve the bottom to mid range are the way to go. Then set the bikes gearing up to capitalize on the torque. Otherwise your better off just getting one of the newer 4 stroke mx bikes, they are lighter, and built to rev to unholy rpms! :bonk:

good point....thanks for the insight guys...

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