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Rear cylinder not firing

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  #1  
Old 04-10-2024, 06:28 PM
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Default Rear cylinder not firing

Hey, everyone bike was running great yesterday and today the rear cylinder stopped firing. I checked and the spark is good. Compression seems good, but the pipe is cold.Maybe timing? It's got a point system that will soon be replaced by an electronic ignition...initially stumped...
 
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Old 04-10-2024, 06:55 PM
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Swap the plug wires and see if it follows
 
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Old 04-10-2024, 06:58 PM
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Smart.
It did not follow.
 
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Old 04-10-2024, 07:01 PM
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Got a compression gauge?
 
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Old 04-10-2024, 07:06 PM
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No but I'll get one tomorrow
 
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Old 04-11-2024, 06:20 AM
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I quickly checked the pushrods to see if they were super tight and maybe causing a valve to not fully close. They seem adjusted properly - they should be hydraulic lifters, right?
Also, it will occasionally backfire through the rear pipe if I try to add some throttle but that's the only sign of life from the rear cylinder at the moment
 
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Old 04-11-2024, 07:31 AM
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Intake leak or a bad condenser.
 
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Old 04-11-2024, 07:32 AM
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Swapped spark plugs and wires?
 
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  #9  
Old 04-11-2024, 07:58 AM
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I'm gonna yank the carb and intake and reinstall with new stuff.

I have a new ignition enroute...

I did swap the wires and plugs and misfire stayed in the rear.
 
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Old 04-11-2024, 08:27 AM
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Firing the parts cannon I see. Need to bear down, diagnose and find the problem. Far cheaper in the long run.
 


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