Topic: Spark units reason for not starting or getting spark?

[Bjones89]

Ive been trying to get my bike started and there's no spark, starter spins but it doesn't start could the spark units be the reason why? cuz the manual says check the coils then ignition resistance and they check out so replace the spark units any help is much appreciated.

[PeWe]

Kill switch activated?

[Bjones89]

Well about that... It's a cafe racer so I have a new ignition and no kill switch...  But the starter spins no spark

[evinrude7]

how do you send voltage to the coils with your wiring scheme? 

[Bjones89]

It's the stock wireing just moved to a electronics box... Also how do u text coils for 12 volts? I tested resistance at pigtail connections not plug wires got 2.6 and 2.5 on both

[evinrude7]

maybe this will help.  http://www.hondachopper.com/garage/troubleshooting_charging_system/troubleshooting_charging_system.pdf

[Bodi]

What model/year?
Only a few later models have "spark units" meaning electronic ignition with sensors rather than points on the ignition plate. Lots of aftermarket stuff possible for older models, but nothing except points was stock.
With stock points and 99% of aftermarket ignitions you need +12V on the coils, both coils have one primary wire, both connected to one power wire going to the kill switch for this +12V.
The other primary wire goes to the points or an aftermarket ignition module.
If you do have late model electronic ignition the wiring is very different. Get a Honda official wiring diagram for your year and exact model and work from it. The spark units are known to fail, I do not know how to test them.

[Bjones89]

It's a 81 Honda cb650

[Bjones89]

Is 2.6 and 2.5 on the primary coils good?

[DaveBarbier]

Yes Bjones, the ohm reading you’re getting is fine, as I posted in your first thread. I also posted a wiring diagram there and how to test if the coils and spark units are getting power. If they are getting power and everything else checks out, I’d replace the spark units.