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rev box for 250ex?!?!?!?!?
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Posted by: mustang25

i was considering prchasing a big gun revbox. It costs $130 and increases the rev limit by 750rpm's....is this worth it??? (i have already installed an exhaust, jet kit, and air filter)
-thanks

Posted by: 250exkid

iv heARD that you gotta watch out on over reving you 250 cuz your taking the rev limite out of the motor there usually set for a reason.... blowing motors.... but thats my guess that i wouldnt get one but idk i dont no any one that has one even

Posted by: Pipeless416

quote:
Originally posted by mustang25
i was considering prchasing a big gun revbox. It costs $130 and increases the rev limit by 750rpm's....is this worth it??? (i have already installed an exhaust, jet kit, and air filter)
-thanks

buying a +750 rev limiter might actually be beneficial on a 250ex since its so easily reached in 5th gear. it wont make a huge difference, but it could help your top speed a little bit since the stock limiter is set relatively low.

Posted by: 250exkid

reallyy??? tell me more.... but iv only seen rev limiters for +1000 rps! so yea what about that?

Posted by: Pipeless416

quote:
Originally posted by 250exkid
reallyy??? tell me more.... but iv only seen rev limiters for +1000 rps! so yea what about that?

rev limiters come with all kinds of limits with most of them being +1000 or 1500. The engine will be fine with the +750 or any of them because its unlikely that it will be held at WOT for a long period of time anyway. my 400 has a +1000 on it and while it really doesnt make a difference since it stops making power after about 7500 rpms i believe.. but it does raise the top speed by a couple miles per hour. for the 250 it might actually be beneficial, but not so much on anything where the gearing can be changed.

Posted by: 250exkid

how big of a chance do i have on blowing my engin with a 750? now im not an idiot that would have it wide open for a long time also

Posted by: ryanh250ex

I wouldn't bother unless you have a ported/polished head and/or a cam. If you had these mods AND a rev limiter it would do wonders. Without them? It's a waste.

I run no quiet core/spark arrestor and just run a filter off the carb (i.e. no airbox) and I find that even my peak power is there well before the rev limiter. I dont see how you need it.

Posted by: 250exkid

oh ok i was just woundering........ yea run with no spark arrester/queitcore...

Posted by: huggy23

I just put a Amr racing rev box on my son's 06 250ex and you can tell the diffrence on the top end. He has the HMF full exhaust, 110 main jet and the K&N air filter on it also. They all work really well with each other.