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Ocean1
19th November 2011, 17:11
The boy's bike, ('91 RMX) won't start.

How hard can this be? It's got fresh fuel, spark, (p'raps a bit weak) and I'm getting fuck all action.

Compression feels normal, it's a new plug, (which is wet when I pull it out) but I get just a vague chuff every 10 kicks and that's it. Same crashing it down the road, very occasional fire sounds more through the pipe than anything.

Pre surgery checklist: Rotor moved? Flywheel key sheared?

Anything else I should check?

Cheers in advance...
paturoa
19th November 2011, 17:38
So you changed the plug and now it doesn't go? (was it running before you changed the plug?)
White trash
19th November 2011, 18:03
Ignition timing?

Failing that, try another plug.
Ocean1
19th November 2011, 18:16
So you changed the plug and now it doesn't go? (was it running before you changed the plug?)

It was fed an over-oiled mix, with the expected result. The fuel was replaced, no luck. Carb was flushed and a new plug fitted. No luck. It's been unresponsive ever since.


Ignition timing?

It does have that feel about it but the only way it's changed is if the stator's slipped or the key's gorne.
White trash
19th November 2011, 18:19
Pickup coil hasn't come loose? Wouldn't be the first for no apparent reason.
Ocean1
19th November 2011, 18:22
Most of the prime candidates are in that area, I'll pop the cover tomorrow and have a rummage.
paturoa
19th November 2011, 19:10
Try kicking it over with the plug out and earthed against the head. Nice bright blue spark?
Ocean1
19th November 2011, 19:36
There's a spark. It's not that bright, but that was in full sunshine...
cheese
19th November 2011, 20:11
Put a new lead and cap on it. My old RM was like that.
Ocean1
20th November 2011, 15:12
Put a new lead and cap on it. My old RM was like that.

OK, cheers.

The boy and his mate, (good mechanic) had a further play today. The flywheel key is apparently OK, not sure what else they checked behind it. Anyway, they cleaned and kicked and cleaned and pushed and finally got it firing more betterer. Still not right though, apparently the best they managed was a 30sec low throttle run down the road, making plenty of smoke. Further tinkering will have to wait for next weekend...