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07 rmz 250 bottem end

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i got a fever and the only perscription is more bottem end i have been working on a a 07 rmz 250 and need more bottem end power been working with it for bout 2 months i think i got everything avalible of it but need more bottem installed a pipe jetted it got valve seats & springs cams running mr9 fuel has instant response but not enough bottem any advise would be good

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got 3 450's bigger rear sprocket doesnt give you bottem end jst makes your gears shorter so you have to shift more cant big bore has to be stock displacement for nationals

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The common thing to do is to raise the compression and have it ported but if you're talking about a national, are you sure you need more bottom? The RMZ at least stock has really good bottom end. Power nows, heavier fly wheels all help a bit but it seems kind of waste on an outdoor track if that's where you're racing. In any case if you're really serious about this I'd ask pro circuit or WB( Tom Morgan) or any reputable engine builder.

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Are you kidding me? The RMZ almost has too much bottom end, and I race on a pretty serious level too man.

If anything, I'm trying to line it out a little better, actually sacrificing all that bottom end to add some top.

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well thanks for the tips but our bike are full works procircuit bikes and i am just trying to see what kind of ideas people have that i may not have or procircuit hasnt have my rider is a factory amature we got more compression i was working on it at pro circuit the sada heavyer fly wheel would kill it and we tried the power nows they didnt do anything so thanks for the tips man

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Well if you have a full pc setup i doubt we will come up with much to improve on them, why the obession with bottom end, the std is good and i am sure a pc 250f has more than std.

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like suz109 says, go one tooth larger on the rear sprocket.thats what they did during a test. it brings 2nd and 3rd gear closer and gives more bottem end. let us know how it works out...:applause:

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go up a toooth on the rear sprocket,,, will give u better acceleration=mor low end power

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like suz109 says, go one tooth larger on the rear sprocket.thats what they did during a test. it brings 2nd and 3rd gear closer and gives more bottem end. let us know how it works out...:applause:

I would second this thought; I went up 2 on the back; night and day difference - bike pulls great out of corners now.

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IM just getting started on the 07 RMZ 250 and am excited by the new head desighn althoughit apears that there may have to be some reworking of the floor in the intake port i havent taken full measurments but it apears to be to large just before the apex on floor which means some filling in basicly the air is coming in and then loosing some energy by expansion ,the KTM 250 is also like this but more severe and is the reason for there midrange softness .the roof looks to be taller than the crf 250 which is good im able to inprove the crf heads by over 20 cfm @ 28" h2o by reworking the short side .with the increased roof on the RMZ i should be able to make a better head than the honda .my curent hondas are @ 43 hp with a 99 decibal exhaust and over 21 foot #s of torque .the suzuki has a distinct advantage with its valve train and will alow me to use cams with quiker velocities i see a 45 hp suzuki down the road a bit .RHC

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IM just getting started on the 07 RMZ 250 and am excited by the new head desighn althoughit apears that there may have to be some reworking of the floor in the intake port i havent taken full measurments but it apears to be to large just before the apex on floor which means some filling in basicly the air is coming in and then loosing some energy by expansion ,the KTM 250 is also like this but more severe and is the reason for there midrange softness .the roof looks to be taller than the crf 250 which is good im able to inprove the crf heads by over 20 cfm @ 28" h2o by reworking the short side .with the increased roof on the RMZ i should be able to make a better head than the honda .my curent hondas are @ 43 hp with a 99 decibal exhaust and over 21 foot #s of torque .the suzuki has a distinct advantage with its valve train and will alow me to use cams with quiker velocities i see a 45 hp suzuki down the road a bit .RHC

Where is the sacrafice going to be? I know a lot of times you have to give something up, sometimes sacrificing bottom for top, or visa versa. Also, what is this going to do to reliability? I'm seriously interested down the road when you're ready to start taking order, I just am wanting to see what I'm going to give up. Also, any idea in the world roughly what cost would be?

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if the motors are done by procircuit whay are u askin us? ask mitch payton or the guys in the engine development side of procircuit....a 250 f that already has killer bottom end best in class by far ....u should be lookin for more mid to top to make the powerband more linear and honestly anyone who is amatuer/expert speed on a 250 f is most likely not gonna have that bike below 6 grand on the race track.........

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if it was a full pc ride, which would pretty much be a villopoto bike (except suzuki), and if you don't think it has enough bottom end, then you do need a 450. I don't mean to come of an *********, but it kind of sounds idiotic to have a pro circuit 250f that doesnt have enough bottom end, and again, dont mean to come off as one, but either, your stupid, or pc cheated the shit out of you.

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