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250 XCFW Engine ....Compression Test?

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I have the factory manual for this bike and nowhere in it does it cover doing a compression test. How do you do one with the automatic decompressor and what should the numbers be. I'm having problems with this engine and would really appreciate any help you might throw my way.:thumbsup:

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I have 07 250xcfw. How do you know if your auto decompression is working correctly.

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Throttlejockey.... It's been holding up very well I've now got 215 hrs on a HT 280 kit. Did a major this winter from crank bearings ,timing chain and lots of other stuff then dropped in a new piston. The problem is I screwed something up, probably not enough assembly oil on the one cam so yesterday on it's maiden voyage it seized for a second then broke loose. The bike wouldn't start but turned over all right so I thought I had seized the piston. I found out today it scuffed the exhaust cam slighty and it wouldn't rotate fast enough to disengage the auto decompressor so with no compression it wouldn't start. Got it cleaned up today and hopefully it will be all right. Did heat cycles for about 30 minutes with the garden hose keeping rads cool. Next weekend I'll see if it's good or if I need new cam bridges.

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When you do the test, the throttle needs to be fully open and you kick until the gauge stops rising (usually around 115 psi for a good comp). I've also heard that you need to hold the kill button to prevent electrical problems (?).

Good luck,

MrHix

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Or to stop the bike from starting I would assume. Can you just use the magic button to do the compression test?

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I don't think the electric start turns the engine fast enough to give a good reading.

I have a toggle kill switch so it makes it easier.

Cheers,

MrHix

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