No spark, everything else works 100% fine

[Lord Percy]

Why is it that I can arrive home on a perfectly working bike and then in the morning it's just dead?!?!

There's no spark coming from the HT leads. Everything else seems to be 100% ok - lights, indicators, starter motor (lots of power but obviously will drain eventually), etc are all totally fine as far as I can tell.

I've checked the leads for a spark and there's nothing. So what the hell has happened over night? There are two leads and both are dead. What could this mean? What should I check??!?!?

I've taken off the seat and tank and can't see anything damaged or unplugged. If a component is broken, which one would it be? Is there are way I can check if I don't have a mulitmeter.....?

I suspect something like the kickstand cut-off but that seems fine too - when the stand is up, the light on the dash turns off, so I guess that circuit is fine. I can't think what else to check. It's just odd that it's suddenly completely died over night. Not a single chug of life in it this morning, the engine just turns and turns.

It's a Honda CMX 250.

Thanks

[Lord Percy]

Killswitch

[cb1rocket]

Not the only one you know

Cue thinking of me breaking down in the desert of Nevada while in Las Vegas doing the Valley of Fire ride out!
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[Teflon-Mike]

CMX uses the same self excited ignition as the other benley engines I believe.
The motor needs to spin pretty well to get enough amps out of it for sparks. Have had bikes show all signs of life but a spark, and its been that they are just not turning over fast enough.
That's first check.
Second. you say you have checked the HT leads for spark. Have you pulled the plugs? Shitty plugs need more electric to get past insulating soot and crap on the electrodes. Worn plugs will have lost the edge to their electrodes and again, makes sparking harder.
Ignition system is otherwise pretty simple, and if its working when warm, unlikely to be the trigger inductor; CDi or coil. BUT its a 'make to kill' ignition; turned 'off' by making a circuit through the ignition, kill or side-stand switch.
So I'd be tracing the, I think it's black/white wire swuibbing switches with WD40 and looking for a short from fretted or melted wire
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[Lord Percy]

Cheers for the info BUT, check the second post in thread

[Islander]

[Fizzer Thou]

[Lord Percy]

I just find it hilarious that I went to such lengths before discovering how stupid I'd been. Even called work and missed my shift!!!

[Fizzer Thou]

There was a BCF member in my workshop the other year learning how to do a simple oil and filter change to his Triumph.When it came time to start the engine it just did not want to know.What made things more difficult to diagnose was that there were handlebar/handguard muffs fitted and so we could not see that the kill switch was operated.Took a good few minutes of head scratching before that was realised
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Just talk bikes.What else is there?

Always have a 'Plan B'

[Islander]

I think everyone who's ever owned a bike with a kill switch has done this at least once.

[MatteyA]

I did a similar thing with the sidestand safetly cut off when i first got the bike. Couldnt understand why it idled fine and would cut out when i clicked it into gear to pull away. 4 or 5 times of doing that it occured to me the side stand was down.
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CBF 125