Hello new on here ,,,it started 2 days ago running fine then yesterday sounded like it was running on 3 cylinders and back fireing ,,today when started sounded like 2 cylinders and one big back fire and stopped ,,,,,so pulled tank off checked plugs and theres no spark from any of the leeds so i ruled out coils as i think it would be back luck for 2 at once to break,,,,this is a 1997 cbr 900 road bike about 28000 miles even checked the timing chain and replaced the pulse sensor still no spark,,,,, im geatful for any direction

 

@theproc Hi and welcome to the forum. Do you have power (12v) going to the coils? That 12v is coming from the Engine Stop switch. Could also be bad connections at the ICM (Ignition Control Module).

 

il check this first thing and let ya know how i get on cheers

 

Well up and at it and there is 12 v at the coil wires and the kill switch works zero volts when off and 12 v when in the run postion is there a test i can do on the cdi

 

you may check battery voltage at the CDI by unplugging its socket and testing the Black/White line there.

 

I will check this after me coffee cheers

 

i have checked this black white wire at cdi and its got 12 v

 

i think the voltage is ok and the line is fine.
i would check pulse generator path next. you may check for the continuity of Yellow and White/Yellow lines which runs from pulse generator harness side to the CDI socket.
check continuity from pulse generator harness side Yellow to CDI side yellow line. then pulse generator harness side White/Yellow to CDI side White/Yellow line.

 

i will cheers

 

i have checked both wires they are fine from the plug to the cdi dose this model have problems with egnition