Okey so i got a 92 cbr for classic racing
its been sitting in a grage for a couple of years so when i got it the oilcooler was gone so i couldent test it.
So i got a new one and the bike was like new after a good carbclean and sync.
The idlejets was plugged all 4 of them but i managed to bumpstart it at first
Carbs are like brand new
New plugs and wires
fuel is drained and everything is cleaned up and working fine
so her is the problem the engine cranks over and its like it will start but backfires and just dont wont to run
checked the spark and it looks a little weak but
the battery is fully charged
im running out of ideas here what to look for

Cant win if i can start the bike

 

The only time mine has backfired was when it wasn"t getting good fuel flow.