Dr Big

Full Version: No spark. CDI fail?
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Hey guys, I have no spark on my bike. I have replaced Pick-up coil and Power source coil, because of wrong/no values on multimeter, but I still don't have a spark. Ignition coils seems to be ok (correct resistance). Tried with 4 new spark plugs.
Can be the CDI faulty? (I have read they are very rarely faulty) And if so, why is this happen? I don't want to buy a new one and find out it's another problem. Or damage the new one somehow. (is it even possible?)

I have 2 CDI's, but don't know how to measure them, because they have strange cable colors:
Test the obvious things first:

All wires soldered well onto the base of the ignition switch (no broken connections)?

Is the side-stand switch working properly. Wire around it to be certain

Is the “kill switch” on the right bar operating properly (not sticky, not shorted etc)
99% of the time on a Big it`s an earth problem, so check all these first.
Also, check the blue neutral wires as well, as it won`t fire up if the neutral is not connected.
Is the engine turning over on the starter OK?
Engine is turning (lights are OK too). Kill switch looks ok.
Yesterday I cut off the side stand switch. Engine is still turning, no matter if the wires are connected or not. Why?
The side stand cut out swtch will only kill the engine if it is gear, but will turn over in neutral
It`s to stop people riding off with the side stand down
Of course. [headbang]

Blue neutral wire seems to be ok. Even cables on the ignition switch base.
Have you checked the cable connectors between the alternator and the wiring harness and also the one to the CDI from the harness, open them up and make sure there is no corrosion....I always fill mine with vaseline to try and keep the moisture out.
It may also be worth doing a continuity check between the alternator, ignition switch and the CDI in case of a fractured wire or poor connection.
Good luck.
Connectors seems to be ok, continuity too.
I opened the harness and that red wire from CDI is cut off.
Where should it be connected?