Motorcycle Repair: electrical hell, fuel compression, primary resistance

Question
hi, i have a 2001 custom,with a 100 cubic inch Revetech motor. I went o ride it and it started ruinning on one cylinder. i thought it was the coil but swapped it out with my dads from his harley and it did the samr thing. i cleaned and adjusted the carb, and still the same. once machine is warm and has been sputtering for a while it will hit on both cylinders sparadically. do i have a ignition problem?

Answer
Hi,Aaron.  Did you check your spark plugs,and or plug wires.Make sure they both have a strong spark.It sounds like the rear cylinder is the problem.If you have a good spark at both,then check the compression of both cylinders, making sure you have no more than 5% difference between cylinders.If all checks out well than make sure all connections are tight and not broken at the battery,coil,pick-up,main and circuit breaker.He are some tests you can do for the coil and plug wires.Check the resistance of the wires(~250 ohms/in minimum of wire length,Coil primary resistance should be 4.0-7.0 ohms, and secondary resistance should be 10-14 kohms.)Try some of these , but remember it takes fuel,compression and spark to make the motor run.Let me know how your test results are and we can go in more depth if the problem consist.