Why won't my bike start?

[NATHAN O]

1979 Suzuki GS 850. Getting gas and spark into cylinder, but will not fire off. Bike turns over fine. Getting small fireballs from cylinder, but thats about it.
1979 Suzuki GS 850. Getting gas, spark, compression is good. New spark plugs and small fireballs out of cylinder. Bike will not fire off.

 

[molitor]

Bike needs 3 things fuel, spark and compression, all applied at the right time to work. Got compression? Cam & ignition timed right? Was this a runner before?

 

[Choppy C]

sounds like a timing issue!

 

[the_white_knight]

Check the compression. It could need new rings.

 

[Rod Knocker]

are the carbs out of sync? Valves adjusted properly?

 

[emucompboy]

If this bike has a distributor, it's time to check the points and the little rotor thingie in there. If the little rotor thingie is too loose on its shaft, then it's not doing the correct spark timing.