Motorcycle Coil Testing: The Basics

In this video we dive into some basic tests we can apply to a large amount of the coils used on older or more simplified systems.

I personally think the tips towards the end of the video will really help people understand the bigger picture of how your motorcycle electronic systems live and die by the stuff we do to them.

Enjoy!

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[TheHandyman]

Cody, your videos are base knowledge, and if you are clueless like most people are some information is better than nothing. I'm old now and do homework every time I have to troubleshoot anything I'm working on. I say thanks for your information.

[kenhughes]

I watch my unfair share of bike repair videos. This guy actually doesn't make me want to poke my cochlea's out with a multimeter probe!!! Informative / pithy/ clear/stayed on topic/ and no bullshit.. light-years better than 99% of repair videos I've seen.. thanks a bunch .
Audi 5000
Krh

[MCoyne]

Thanks for sharing your knowledge of ignition coils, my nearly 50 year old bike thanks you.

[Desaltvoider]

This didn’t help me get to the very bottom of my problem (yet), but I learned a lot and I really appreciate you taking the time to be this thorough and share your knowledge. For someone just learning by wrench away in the garage your videos are really helpful! You do a great job sharing your knowledge in a way that is digestible to someone who is learning. Thank you

[timothybush]

I feel as if I'm better prepared to tackle my ignition timing problems on this old Ironhead now. You're the man, brother!

[EndlessBatterySolutions]

You solved my problem with this training. 1 year! My bike has been dead for one year! I get it now. I needed that base knowledge to eliminate the working from the dead.
It was a bad spark plug cable to the coil…….

[bethrobertson]

Just so clear, easy listening.
I love it Cody. Can't wait to do free coarse, I think you make a great teacher. wish i could work for you.

[waynemcintosh]

I needed to help a friend fix his bike thanks for giving me the low down and the straight scoop it was informative and concise I totally appreciate it

[scandinerdian]

Dude! I was just working on my bike trying to figure out the whole HT debacle, and your video just made it a thousand times more comprehensible. Thanks a bunch!

[dfrontierit]

Thank you very much for your tutorial videos. It helped fix my Honda Jade 250 even when many other technician could not.

[andrewmanson]

Best explanation I've found on coils, especially two HT leads out of one coil, and the bit about seeing how far the spark will jump is so good. Many thanks.

[paulwakefield]

Thanks, Cody, for the informative video. It helped me confirm the problem of no spark on 2 cylinders.
It's always nice to be able to fix my bike, sometimes with a little help. This time, it's from you.
I have a 1984 Honda Goldwing GL 1200 Aspencade.

[abruptlyblunt]

@ i little heads-up to share, I took out one my coils on my bike when I didn't see that the little screw-in brass insert inside the cap which locks onto the the plug fallen out when i pulled the cap. When i put the cap back on I was in a hurry and didn't notice that the cap didn't lock on like usual, and when i took off riding after just a couple miles the bike started popping and dropping cylinders then lost both cylinders for that coil, when i tested coil the secondary side was completely open. Moral of the story, when you put the spark plug cap back on the plug i make sure and listen for the metallic clicking of the insert sliding down the threads on the top of the plug !!!

[thisguy]

This video is freaking perfect. Good format, well presented. For me personally, perfect pacing also.

[Dr_Reason]

A coil is a "transformer" It makes a magnetic field with 12V and a couple of amps flow. Then when the voltage is cut off this sudden change creates a much higher voltage, but lower amperage, current potential at the output terminal. This voltage is so high it discharges through the spark plug gap to ground. The resistor caps cut this flow off after a few milliseconds or otherwise the longer pulse would cause a lot of EMF interference, messing up radio, tv and even the sensor readings on newer vehicles.

[AlexanderTheGrateful]

Mine are a pain in the ass to get to them so I’ve checked everything while they’re still mounted and couldn’t find the issue.
Today I will remove them and check them for cracks. I have an intermittent issue with mine like you described,

Thanks 🙏

[alexpino]

Thanks a lot Cody, very useful information, thanks a lot for your time doing these videos, I will try that on my '84 Magna tomorrow, thanks again!

[Spitfireseven]

You did an excellent job here. The really crucial thing you did, as far as I was concerned, was pull the cap off the wire. I just made this discovery on my Suzuki Intruder. There is no way to get the cap through the frame to the plug. As I pulled off the old wire the cap came off. Low and behold there was a copper screw in the cap! This screwed into the coil wire! I never dreamed this was possible. It screwed back on too, and tight! WOW!!!

[stevesvids]

Nice one Cody. You've no idea how much great info comes across in these vids. We are like your apprentices soaking up all that knowledge.
Cheers man. Very helpful indeed. In particular I love the 'jumpage' test. Thats a little chestnut of info. 🙂👍😎
Steve 🇬🇧🇺🇦

[benp]

Dude, your videos rock! I would have needed these in 2015 when I refurbished my Bandit 600, but now they come in handy for a XBR500 get-it-to-fire-up job for my girlfriend. thanks for sharing your knowledge