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New to 2 strokes have some questions

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just a few days ago i picked up a 1992 KX250 for $130. i drained all the fluids completely cleaned the carb. i dont know how the reeds are supposed to look but they dont have any cracks and there is only a very small gap barely visible. i think the compression is low because if i press really hard i can hold my finger over the plug hole while i crank it. is this normal for 2 strokes or do i have bad rings?

after all that i eventually started it but it takes a lot of effort. im going to rent a compression tester later today and report back with the numbers. so basically what im asking is, do you think its the reeds maing it hard to start or the iffy compression? thanks in advance

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both the reeds and worn out rings would make it hard to start. there shouldn't be any gaps visible in the reeds, i would replace them.

It is a good idea to compression test the engine, being a '92 it most likely needs a fresh top end, i would do it anyway just for peace of mind.

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you could try flipping the reeds and see if they seal up again,I did this to my old reeds and it worked.If the have any cracks or damage then just replace.My guess is worn out top end,check the cylinder before installing new piston.

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i tested the compression and got 120psi which sounds okay to me. but i did take out the reeds and cleaned them real good but i still couldnt get them to seal. which reeds do you all reccomend ive been looking at some boyeson superstock reeds

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The compression is on the low end, but it should run at that. You should be around 160 when rebuilt. Boyesen reeds will last a long time. I would change the reeds first and test it.

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think the kawi website states around 171 psi but 200 or above is common,120 is getting low but still should run,like I stated try flipping the reeds if they aren't chewed up.

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i ordered some Boyeson superstock fiberglass reeds today should be here soon. i think the top end rebuild will have to wait till another paycheck or two because the previous owner said "i think its bored over too"and he was right. it has a sleeve in it instead of plated and it has a Hot Rods connecting rod, dont know how much its bored over but im assuming that an overbore piston can cost a pretty penny. also i dont know what the ignition timing should be set at.

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Should be a Wiseco piston if overbored and avalible through LASleeve and cost very little more that a stock Wiseco piston.

Ed

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