I generally don't ask tuning questions....

MB

Coast to Coast
......because I generally find that with patience and understanding it
all gets figured out, but this has me stumped. I have someone coming
to buy the bike on Monday, which I need as my wife just lost her job,
and I gotta get her running sweet! 71 cb 350 ubiquitous megaphones and
pods Jets 105 and 70 (the stock jets worked best for me all last
summer, I got a decent tune that was stable and rideable over all RPM)
Got a nice even tune, around 1000rpm, warm. My usual test track is
some Brooklyn back streets, a bit stop start, all revs exercised then
a hill for 20 blocks with lights, then a u turn and WOT back down,
then some more stop start. About 10 minutes. The bike is warm when I
do all this. Returns to a nice even idle with no throttle blipping
needed. It performs really really great until AFTER i go flat out at those high revs.
bike feels great at WOT (better than I had her tuned last year) and I
don't feel like anything is missing. Then when I slow down to a light,
it'll usually die. It will however, kick over first kick and idle the
same again. But after this, the bike is jerky, will idle correctly but
will drop in and out at higher revs.
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As you can see both plugs are slightly carbon fouled (I don't think anything crazy forge amount of idling) with more grey than brown center. Please help me out!!!!!!
 
I have no answer, but I am in the same boat. CB 350 and all. However, this only happens on my left cylinder. I am running the mikuni VM 30's and they are jetted the same, synced, and I even started running hotter plugs (b7es).


Next I am gonna check timing and compression. but i just check them a few weeks ago and they were good.


I also thought maybe it was dirty or clogged filters so I cleaned them and they are drying now. If that doesnt work then i guess i recheck the above.


Let me know if you figure this out. Thanks a lot!
 
It was suggested to me by a buddy with a "hunch" he won't reveal that I check battery voltage at different RPM tomorrow. I'll let you know what happens
 
Thanks a lot. I had a bad battery awhile ago that caused me to foul plugs but this new battery is fine, atleast I think. Maybe I should drop the money for a nice gel battery?
 
The problem in this instance was incorrect hook up for the aftermarket reg/Rec causing spark problems by dumping crazy V's into the electric manifesting as irregularity at the Spark
 
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