Early rev limit?

[GSlowTWIN]

Hey guys first post here! Got my GS500 a few months ago not running. Had to rebuild the carbs, shim the valves, put a battery in it, change the oil, and a couple of other things. Finally got it running and have been riding it a week or so now but I've noticed it is cutting my ignition out really early. Like 8,000 rpm it limits out. Done some research and have read the the rotor spins past the signal generator, creating a rpm signal to the ignition assembly letting it know about load and rpm's. Is it a bad ignition module? or bad signal generator? How do I test these?

[rscottlow]

**snip**
or bad signal generator? How do I test these?
**snip**

Signal generator can be tested with a ohmmeter. What year is your bike? The older models have 2 coils, the newer bikes only have one. If you have a Haynes manual, the resistance specs can be found there.