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rm 265 kit

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If you haven't already I'd recommend a good port job. A well ported cylinder, with a good pipe, and carb jetted to the porting, will add a lot of power. Probably quite a bit more than just boring the bike out to 265.

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the porting on the rm is pretty good, the big bore just adds power everywhere, plus Eric Gorr ports every cylinder he big bores anyhow- its included in the price along with head mods...i think its around $500 for everything, but dont quote me on that

http://www.ericgorr.com/

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Depends what year your talking about... Early to mid 90's RM250's are real torquey in my experience without much over-rev to speak of. Add an extra 20cc's to a motor already lacking in high end it's going to make it a tractor but kill any topend it had because the motor is going to be trying to pull more air in through the same smallish ports that already didn't support the high end. I'm not arguing with you, you probably know more than me about it I'm assuming you have a 265. I'm just saying in theory you might "need" a port job to get all the power out of more cubes, and the motor "could" make more power with just porting than just a big bore. Just boring "could" just move the power curve around, not have an effect on peak power.

But since Mr. Gorr does porting on big bore cylinders as part of the deal... I'm guessing it's a moot point. It would be interesting to see what his porting on a stock cylinder would do to power vs. the power on an unported big bore cylinder vs. ported big bore. Wonder what that would look like on a dyno. 👍

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its a 2006,but man xr250rdude u have me wondering now, that would be a good to see with all them, if i had that much money to throw aorund i would do it in a heartbeat. but is there anyway i can get a rm265 and get the phat head racing head on it with interchangable domes?

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its a 2006,but man xr250rdude u have me wondering now, that would be a good to see with all them, if i had that much money to throw aorund i would do it in a heartbeat. but is there anyway i can get a rm265 and get the phat head racing head on it with interchangable domes?

ive got the 05, the 265 kit is really good from Eric so i am talking from personal experience. All modern bikes have really good porting, so unless you want to sacrifice bottom for top or vice versa, a porting job wont net the returns like a big bore that usually add power accross the spectrum (provided the tuner knows what he is doing and re-adjusts the ports after boring).

as for xr250dude, as he admitted, he is just "guessing" :worthy: so you might want to consider the opinions of people who have actually had any of this work done.👍

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as for the phathead, the 265 piston is relieved at the edges so it works with the stock head, but the compression will be higher than stock, so some material will need to be removed from the dome- you will have to do the same with the aftermarket head.

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as i was talkin about xr250rdude i was talking about seein the stock motor with porting, and just a 265 kit. see how they numbers compare

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