Can someone please advise

[MSTRS]

I am having trouble with my XR250 - won't start. It backfired whilst kicking over & it's no-go now. Is there a keyed flywheel that will have 'moved' due to backfire?? There is spark, compression & fuel but am now stumped.

[Posh Tourer :P]

Stupid question - not flooded?

[MSTRS]

Stupid question - not flooded?
Perhaps it is a stupid question - I not know 2 much about mechanics of 'modern' engines. Doubt it's flooded tho - this problem continued for 2+ hours.

[Racer X]

Find a big hill and try roll starting it, use 3rd gear and try with variations from no throttle to full throttle

[MSTRS]

Been there & done that. Hence my pitiful cries for help. Ta for suggestion anyway

[F5 Dave]

Sounds like the first guess does have some credence. The flywheel could have sheered the woodruff key.

But first & foremost most likely the spark plug has failed. Buy a new plug to be sure. Before you screw it in, put it in the cap & see that it sparks when you kick it over (a duff plug may spark outside but not go inside the engine under pressure). Does the plug get wet with petrol? If not, why not?

[MSTRS]

The XR lives! Not so cheap, but crappy sparkplug spat the dummy. New one installed & try to stop me :spudwave: Ta for suggestions guys