stuttering engine

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I have a '72 norton commando 750. mostly stock with a mikuni carb. i think the ignition may be updated too. not sure. been running beautifully but just recently I've noticed some stuttering or hesitation, like a skipped beat, while cruising. doesn't seem to matter what gear I'm in. and usually at over 3500 rpm. (doesn't happen while idling. idles very smooth) if I'm just cruising, holding the throttle steady i feel a periodic sudden slight stick, jerk, hesitation, skipped beat... every so often. and sometimes i get a corresponding POP from the exhaust. I'm guessing this symptom may be pathognomonic for something fairly simple. but don't have a ton of motorcycle experience and not sure what to do. any guesses as to the problem? and its solution?

thanks for your thoughts.
 
I chased a slight stutter for quite a while.
In the end.......... it was a bad plug wire.
an easy fix, hopefully yours is as simple.
 
Here we go. Dirty fuel filter. Corroded ground point. Bad battery connections , Low battery.Bad fuse connections, oxidized. Dirty plugs . Bad ign. switch. Let's start with those then report back.
 
thanks. will go down the list and check things out. already cleaned and gapped the spark plugs. no dice. the wires look very new. nkg. not sure where the fuel filter is. will look for it. thanks for the advice.
 
not sure where the fuel filter is

both petcocks should have screens acting as a filter, but you have to unscrew the petcocks out of the gas tank to see the screens, and then some people put a real gas filter right in the gas line from the petcock to the carb

BUT, as you can see from the replies, most likely cause is electrical and that means an intermittent connection,
maybe a ground wire, maybe a points or electronic ignition wire, are your battery terminal connections tight

ok so your plugs look good and you say the plug wires look new, are they firmly shoved into the coils?
 
My hat goes in the ring as an intermittent lean misfire... under steady state cruise, possible carburetor partial blockage from storage.
 
If acts like lean intermittent misfire after some cruise interval then check for intermediate shorts anywhere from tail light to head lamp and definitely always suspect the spark trigger leads under point cover before. After dark wire probing sometimes revealing. Look at plugs for the fun of it to get in mood to mess carbs if need be.
 
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