No power under throttle

crashtest

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I have '81 xs with pamco PMA and e advancer that i had a little problem with today.
I had it out on the road and it was riding a little sloppy like the timing was a bit advanced. When i got on the throttle the low end would pull ok then the revs would continue to rise and it would almost feel like i was slowing down or losing power. It never tried to stall just would not pull like i know it can. What could be causing this power loss? I have the mikuni bs34 cv carbs, im guessing the jets could be stopped up but why would it continue to rev and not die? Any help is appreciated for sure
 
Thanks for the reply Pete. I havent tried the battery swap but have put a multimeter to it. At normal idle im getting 14.4 volts at the sparkplug. Seems high. Before having the problem i cleaned up the wiring to mimic the bare bones diagram that has the e advancer with the PMA. The left cylinder fires randomly but is showing continuous spark with the multimeter.
 
A multi-meter can't show spark. At least none of mine do. You can test voltage at the coil positive terminal but not at the plug. If your PMA is working good then 14.4 volts while idling is good. It should read that much at any rpm cut not any higher. If the voltage does go high it can damage other electrical parts.
Leo
 
Another thing, It may not be lacking power but making too much. To much for the clutch anyway. Perhaps the clutch is slipping. Most noticeable in the higher gears, less so in the lower.
Leo
 
Didnt think of that, ill check out the clutch.
I havent rebuilt the carbs since i picked up the bike 3 years ago, and im sure the PO didnt do it. Ordered the rebuild kit from mikes xs, and started the cam chain, valve check, timing, carb run through. Hopefully its something basic thatll get washed out. Glad that 14.4 is good, scared me for a second.
 
Just took it out for a quick ride and think i have it ironed out.
Last year i got a replacement fuel T that connects and delivers fuel to the two carbs. I remember it was a pain to get it to seat right, reason being the rubber seal had slipped out of place. The result was the left carb was partially blocked making fuel supply to that cylinder sporadic...duh! Im an idiot my pamco still runs like it used to.

Second part of my problem came down to a poor choice in oil, too viscous, causing the clutch to slip. I replaced with Lucas 10w40 motorcycle oil with the stuff for wet clutches. It pulls like it used to.
Thanks for all the replies. File this one under stupid owner
 
Good to know as I prefure thicker oils !
Not stupid Owner.... Your learning ! that is the oppisit of stupid ! keep it up !!!!
before 20 years passes I bet you'll know everything there is to know about on that bike !
each bike is a bit diferent, so just because you know ONE through and through does not mean you know them all !
heheheheh (state the obvious why don't ya Bob ! ) LOL
C ya !
Bob.............
 
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