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Misfire

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Waggles:
My bike developed a misfire on the way to work  :( thought it was going onto reserve but no, that made no difference. All exhausts were hot. tried to 'clear it' by holding higher revs, that didn't work either. I have no doubt I can trace the problem and fix it but my question is, as I have a lunch hour to try and sort it, what are the most likely causes?

I am thinking possibly plugs as she has just been commuting with no open road running for a while, if not, probably fuel contamination / blockage. Any more suggestions before lunch?

SteveD CB500K0:
Only the usual...

Misfire on one cylinder - probably plug or HT lead
Misfire on two (1/2 or 3/4) - fuel flow to carb feeds
Misfire on two (1/3 or 2/4) - ignition LT or coils

Let us know how you get on.

Waggles:
Thanks Steve,

Difficult to know at this stage which cylinder(s) were mis firing as all exhausts were hot ( mind you she was running OK for half the journey ) so will pull the plugs first to hopefully get a clue. It felt more like one cyclinder out as power was seriously down. Will check the points haven't come loose too.

Plugs are only a couple of hundred miles old, coils leads and plug caps all new too ( mind you the coils are pattern parts and I am getting a bit cranky with bad aftermarket stuff .... )

Will let you know.

mick:
Hi it could also be a condenser going faulty i've had that before causing  a misfire  ;), cheers Mick.

Waggles:
Cheers Mick,

Condensors and points also new, but will check connections

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