Yz250 crank shaft flywheel stripped problem!

I was installing this flywheel to make my bottom end go up and i realized my bolt was stript i take it off and i realized I shouldn't put the fly wheel on no more and leave alone, so I put all of it back together the bolt back in and I go to start my bike (kickstart) and wouldn't start it'll crank but not start, So I check my sparc plug and it was bad so i cleaned it off and tried it again but when I put the sparc plug back in the compression gets really strong and its really hard to kick but when I take it out its really easy like i could when it was running, Any how I can't figure out my problem? Do I need a new crank shaft or just try getting a new sparc plug? 

Edited by jacob_buttery

Bike won't run with flywheel off.


I like english better.

harder to kick over with plug in because the motor is building compression, plug out all compression is blowing out.


as posted bike will not run without flywheel because the magnets in it generate the power to spark the plug, and trigger the spark at the right time


some flywheel bolts are left hand thread, sure your turning it the right direction?

Jacob .  .  .  . ummmmmm .  .  .  . WHAT???

You better replace your power band. It's been known to wear out and cause extra compression with the spark plug installed, but no compression with the plug out. Replace this band with an orange ribbed one and you should get good compression.

Orange band makes much spark. Very compression. Wow.

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