CBR250 won't start

[shanebaker7]

hi i own a 93 honda cbr250 it was working fine up till yesterday i was warming it up in the morning before work and it cut out after which i couldnt start it again. after a couple attempts it backfired a bit so i left it. ive since tried changing the battery checking sparkplugs draining the carbies ive even tried aerostart it still wont kick over just backfiring. can anyone help me please.

[Gareth123]

Timing? Caused my bike to foul plugs and backfire badly. It'd still run though.

BTW this should be in the repair and maintenence section.