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No Spark

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Saesneg Shaun:
Hmmm, my k6 is not running.
It blew a main fuse and broke down on a ride last week.
The original fuse box was a corroded mess and just fell apart which I (wrongly) assumed was why the fuse blew.
New genuine fuse box from DSS fitted but still no joy.
I have no spark at the plugs. I've got 12.6V at the fuses but only 10.8 at the coils?

Anything obvious i'm missing before I start pulling the loom apart?

K2-K6:
Check inside the kill switch handlebar installation to see if it's got a problem there.

Also the electrical switch on the back end of ignition barrel can be vulnerable to years/wearing/corrosion too. The switching mechanism is brass pads and copper bridges spring loaded and swung around to make contact with this pins, you can carefully prize the plastic cover open to look inside if that's the area you pinpoint (do it over a tray or similar as the bits can piiiiing) then clean and reassemble with silicone grease or vaseline if you've not got any ;D

Obvious other elements are to just check all connection for obvious signs of corrosion.

Saesneg Shaun:
Thanks K2-K6

Just dismantled the ignition switch and kill switch but no change.
They were both clean. I now have 11.8v at the coils so its improved a bit but still no spark at all?

Oddjob:
Also check the connections on the block connector the fuse box connects with. It's possible they were the fault in the first place and it was them failing and connecting with something it shouldn't that caused the fuse to blow.

K2-K6:

--- Quote from: Saesneg Shaun on May 04, 2022, 02:56:33 PM ---Thanks K2-K6

Just dismantled the ignition switch and kill switch but no change.
They were both clean. I now have 11.8v at the coils so its improved a bit but still no spark at all?

--- End quote ---

Should be ok to spark at 11.8v without any real problems.  If that's a stable v there, then it suggests that the points or something related to them is an issue. 

Points are switching the earth side of the coil on and off, but if they stay earthed all the time (removing earth causes the spark) you'll get no sparking.

Basics, sure you've realistic points gap ? All little washers where the wires bolt to the points themselves look ok ? Any sparks at the points when you crank it ?

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