Before using this site please read the site disclaimer. Also please note that any links provided may be part of an affiliate programme (viz. eBay, Amazon) which helps support the site as I will earn a commission when visitors make a qualifying purchase.
Here is how to check the resistance of the pulse generators - also referred to as the timing pickups - on a Honda CX500, GL500, CX650, GL650, GL700, CX400 or GL400 motorcycle. This is only applicable to those vehicles equipped with the transistorised ignition (TI) - CDI bikes ('78-81 CX500s) do not have these components. For this you need a multimeter! Find the end of the wires coming from the pulse generators and emerging from the pickup cover - if you're doing a triple or quadruple bypass they'll be easy to find at the back of the motor:
Set your multimeter to the 2K Ohms setting:
The wires are in pairs; one side is blue and blue with a white collar:
The other side is yellow (by now - 30 years on - a dirty white...) and yellow with a white collar:
Measure between each of the above pairs using your multimeter:
The resistance reading you are ideally looking for is 530ohms. The acceptable range is 480 to 580 - e.g. within 50 Ohms or about 10% of the ideal figure. In this case both left and right sides were very close to ideal:
Now set your multimeter to the "continuity" setting and check - one at a time - that all four leads have zero continuity to ground. You can have a pickup coil which has the correct resistance but shunts the trigger current to ground, resulting in no spark on that side - so worth checking.
If you're just checking the pickups you're all done, but if you're reassembling and doing static timing check procedure + assessment click here to go back to the main page for that.
In 2019 the server has had to double in capacity to support the growing site... please consider dropping the site a donation to help cover the costs! Check out our Patreon for support options, buy a shirt, buy our apps, use my NordVPN affiliate link to sign up to their service or donate via Paypal:
|Paypal $5 link ->>|
|Paypal $10 link ->>|