Coils 91 Kat 750

[hicks100]

How can I tell if one of my coils are going bad? For a while it thought something was clogged in my carbs because I could be on the interstate cruising and then my rpms would pick up like the bike went into over drive. It would do that pretty often so I went through the carbs and found nothing and now it feels slugish again almost like it's not firing on all cylinders... Also my idle is up and down??? Can anyone help?

Thanks

[Kat_Bobber94]

Use a voltage meter...unless I'm wrong, when you start the bike, your voltage meter (when touching the leads to your coil) should read 12 volts...if 8 volts, or below, you have a bad coil. I THINK

[Stumpy]

Voltmetering your coil outputs is a bad idea. There are THOUSANDS of volts being sent down those wires. And it's not constant. Your average multimeter is going to have a hard time reading that.

Measuring the inputs is ok. Just be careful with coils - if you dont know what you are doing, you can be in for a bit of a shock

[Slofuze]

Start up your engine...... let it warm up...... spit on your finger and touch each tube to see if one is cooler than the rest. Left coil= 1&4 right coil= 2&3. Swap the coils out and do the spit test again to see if things have changed. Start with simple first.