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1994 cr250 newb modification help

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my buddies got a 1994 cr250 its got a fmf gold series fatty pipe and a powercore2 silencer the motors got 175psi, its really fast but he wants it even faster i am not familiar with modifying 2 strokes or any dirtbikes really but i know on a car, head flow and exhaust flow and the cam are the huge factors, but since 2 strokes dont have cams i figure head flow and exhaust flow have a huge impact, he wants alot more mid-top rpm power he was thinking of getting some reeds, a fmf shorty silencer, sending the head to get ported does that sound good?? what reeds would you guys recommend and whos good at porting the cylinder heads?? should he stay with the power core 2?? he says he wants to spend about 500 for all the mods does that sound feasible?? thanks for any help

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Shorter silencer adds bottom not top.Head mods and cylinder porting are the best options for more mid/top just keep in mind he'll probly need race gas with the motor work and jetting will need to be changed as well.Eric Gorr is really good with porting.

Has he tried changing his gearing yet?A simple gearing change,Reeds and jetting can make a big difference and save some money.

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even if it was just ported hed have to run race gas?? oh ok my bad about the shorty i thought since it was shorter, he dont mind race gas or getting it rejetted, he does want to change the gearing with a smaller sprocket in back and a bigger in front for more top speed he was saying maybe, he has a 51t in back, how much does it run to have a guy like that do some porting?? would it be a very noticeable difference with head porting for mid-top,reeds, and rejetting? like enough bang for the buck?

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even if it was just ported hed have to run race gas?? oh ok my bad about the shorty i thought since it was shorter, he dont mind race gas or getting it rejetted, he does want to change the gearing with a smaller sprocket in back and a bigger in front for more top speed he was saying maybe, he has a 51t in back, how much does it run to have a guy like that do some porting?? would it be a very noticeable difference with head porting for mid-top,reeds, and rejetting? like enough bang for the buck?

Not all porting requires race fuel but when you increase compression with head work you usually need it.

Cylinder Porting and headwork should run roughly $175-$300 depending on what needs to be done.

Porting,Reeds and Jetting would mos def be worth the money if thats what he really needs.What kind of terrain does he ride and does he race?

He should try changing his gearing and reeds first and see how he likes it b4 spending the dough on motor mods.He could try a 48 tooth rear for a start,I believe 49t was stock in 94' and then change the front sprocket if he needs more top.

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Keep in mind that every improvement costs something.

Increased compression/ Racefuel, higher temperatures greater chance of seizure.

More top end/ less low end

Higher horsepower/ Less reliability.

And in a race, it's still 60% rider.

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