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Only 2nd cylinder firing

phillyred

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Usual story, bike was running fine last time I had it out. Tried to start it the other day, but the battery was dead because I apparently left the key "on" etc.. So, charged it over-night and went to start it yesterday evening and right away it sounded weird and sure enough only the 2nd cyl was firing, but every so often I could here the other cylinders kick in. Checked the spark plugs which were fine, had spark to all of them etc, good compression and still nothing doing. Any other suggestions to check? Looks like fuel is getting to the cylinders.
 
When was the last time it was running? If the plugs are sparking and your getting fuel to the carbs the only thing left in between is the carbs themselves. Maybe dirty or clogged jets? I'd put some seafoam in the tank and spray some carb cleaner in the air intake and try it a couple of times. That should clear it out enough to get that cylinder running.
 
And what do you mean by "checked the spark plugs". Did you just do a visual inspection or did you make sure that they are firing? I've seen some handsome plugs that ran ugly.
 
Spark plugs looked "wet" meaning looking like getting fuel and sparking when pulled to check for spark. Bike ran fine 2wks ago. Ran some seafoam through it about a month ago. Still on that same tank with the seafoam added. Gonna pick up a set of NGK Nickel Spark Plugs (DR8ES-L) just in case. Will definitely try some carb cleaner etc to jump start the firing sequence. Sorry for the novice questions.. Just trying to help my son get this bike started.
 
No need to apologize! I've only had a bike for a few months, and I was posting this exact question in February. If the plugs are wet I'm going to agree with you and say that the fuel is getting into the cylinders. Which means you probably have bad plugs, or a bad ignition coil. Plugs are a cheap test. I bought the iridium plugs for my bike and they're wonderful. I'd do a visual inspection of the coils for cracks or breakage in the plastic too. I'd imagine plugs will fix your problem though.
 
No need to apologize! I've only had a bike for a few months, and I was posting this exact question in February. If the plugs are wet I'm going to agree with you and say that the fuel is getting into the cylinders. Which means you probably have bad plugs, or a bad ignition coil. Plugs are a cheap test. I bought the iridium plugs for my bike and they're wonderful. I'd do a visual inspection of the coils for cracks or breakage in the plastic too. I'd imagine plugs will fix your problem though.

SO... New set of plugs fixed everything! Bike runs even better than before. Even though the old plugs looked "ok" I guess they really were not. Thanks for your help everyone!
 
Good! Just had the same thing in a 72 cb350. Was all worried it'd be an ignition system problem, but it was $6 worth of spark plugs. Old ones looked fine, but didn't work. Congrats! Enjoy the ride
 
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