I have a Yamaha Blaster with no spark. I tried a continuity test on the engine stop switch. I had continuity in the off position but not in the run. I had voltage from the stat. I was unable to get any ohm reading from the coil so I may have been doing it wrong, but I ran the leads from the postitive wire (orange) and the ground. What, if any, other checks should I try or should I replace the coil?

SOURCE: can't get spark

Kill switch works one of two ways. Either it grounds you out, killing the spark or it disconnects a circuit shuttig ignition off. So...forget the switch for a moment and wrap the two wires together, try starting, nothing ? then separate the two wires and make sure they are not touching any metal parts, try starting again.....now you have eliminated the switch as your problem.....cap off the wires and don't hook them to the switch if your bike is now running....Good luck to you friend....tim

SOURCE: 1987 Honda shadow vt1100c no spark at any plug

The voltage on the coils is present except at the instant of firing. The interruption of the voltage is what causes the coil to fire. The cdi box is what causes the voltage interruption.
The interruption is very hard to detect. You are not the first to be stymied by that box. If you have access to an oscilloscope, I think you can see the pulse if it occurs.

SOURCE: wire connector between stator & voltage reg/rectifier burnt

your voltage/reg. can be tested in a couple different ways check ground res. check res. then revs. bias on diodes you have ac in dc out it sounds like you may have a diode gone bad allowing ac curent to flow causing the wires to get hot

SOURCE: 2005 venture royal star. can't get spark on left

Eventually.Sounds like a bad coil

SOURCE: 2005 yamaha royal star venture. Still haven't

If you have continuity from the coil to the ignitor, the problem lies within the ignitor. The coils function by having a constant battery voltage on the red/black wire (you'll notice that ALL the coils have a red/black wire) - the primary windings in the coil charge up, until the ignitor "grounds" the colored wire (grey and white in the front, orange and yellow in the rear). As the voltage in the primary winding drops, it creates a strong magnetic field - the magnet (laminated iron) in the center of the coil charges the secondary windings, and the very high voltages generated fire the plug. You've already determined that the voltage on the orange wire is higher than the voltage on the yellow wire; that could only be because the orange wire is not being "grounded" on a recurring basis by the ignitor. (You have to remember that the meter you're testing the leads with cannot react to changes in voltage nearly as quickly as they happen; to really "see" what's happening at the coil, you'd need to use an oscilloscope).

Testimonial: "Thanks, the problem was the ignitor. I replaced it with a new one, and the bike works fine. Thanks again."