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a bunch of "will it work?" xr250 questions

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first off, im new to the forum & i have a 86 xr250 motor that im gonna put on a 250x project, so high guys. now that-that's taken care of, here are my questions.

would a 350x or 400ex carb work on my motor?

would 350x/400ex/ xr600 calves fit in my motor (im hoping that one of those will)?

can these be bored out to 77mm or do they need resleeved for that?

how many hp do these motors crank out & what are your opinions of it.

also, what does RFVC (radial four valve chamber?) mean?

will a hotcam or other aftermarket cam for a 96+ xr250 work in an 86?

how would i make this motor handle higher rpms with less to no chance of valve bounce?

ok guys, i think thats all of the questions i can think of for now. Thanks, Js

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without some work, no



~21 stock, ~27 or so w/ 280 kit and pipe

valves are arranged radially instead of each pair in rows

really doubt it, but no one has tried either (that I know of)

it doesnt make power at high revs so its a moot point

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thanks for your help, but i have a couple more questions...

what work do you speak of about the whole carbureter thing (i know id have to make it fit to the boot & prolly jet the shit out of it afterwords)?

when you say yes about the boring, do you mean that it -can-be bored that much without resleeving, or that it cant?

also do you think it would help the power greatly if i ran each exhaust pipe to its own high-flow muffler?

also i run my 4 strokes at full throttle a lot, which is why im asking how i would go about making them handle it better & not have to worry about floating the valves & all (im thinking about getting those honeycomb shaped valve springs that virtually eliminate valvebounve & some other shit, but i dont know if they can make em that small).

also last but not least would it be possible for me *with the 280 kit & highest compression pump gas can offer* to take on a stock or slightly modded 400ex?

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With the right boots you could mount it, it might be too big though.

Yes you can go 77mm w/o a resleeve.

I really doubt its worth the extra trouble and weight.

The XR250 doesnt make its power up near the rev limiter, it makes no sense to rev the crap out of it.

I really cant say, I've never ridden a 400EX.

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