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89 Vulcan 750 running oddly - one cylinder not firing?



After a less than exciting winter, I brought my bike out a week or so
ago to clean her up and make some repairs and do some maintenance.I
tried starting my bike a few times over the past month or so and had a
tough time, mainly due to a battery that wasn;t holding a charge. I
did, however, get it running once or twice.

After replacing the battery and finishing repairs and cleanup, I
started her up. No problems, a little choke, she coughed and then
started up on the 2nd push. The initial test drive left a little to
be desired, however. It seems that one cylinder is not firing
properly... not sure if it's gas or spark related, but it goes
something like this: when I'm idling or lightly twisting the throttle,
my bike feels somewhat underpowered; when I "goose it" a bit, I can
feel (and hear) the other cylinder kick in - I get a small boost
forward and everything seems normal. As long as I'm on the gas, such
as highway driving, she's OK. I can feel compression out of both
pipes, (not a very scientific test, I know) and I checked all of the
plugs to make sure none were fouled. My wires are a bit old too. Any
thoughts as to what to do to determine the issue and how to fix?
Replace wires? clean carbs?
Possibly water or something blocking an idle jet. The easiest fix is to
add some methyl alcohol/methyl hydrate/gas line de-icer to the gas, it
mixes with the water and allows it to pass thru the tiny hole in the low
speed jet.
Did you leave gas in it all winter? Sounds like a clog in one of the idle
passages. A very thorough carb cleaning would be your best bet.
1. New plugs

2. Clean the carbs.

3. Clean the carbs again.

4. Clean the carbs again.