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Loss of power at High RPM's

Indy750F

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My bike seems to start and run fine, but when i pull the throttle into higher rpm it cuts out and i lose power? It is a 1979 cb750F, I put new plugs and wires on it, but the problem was not solved, any suggestions
 
I'll start based on my experience. How do the plugs look after you run it awhile? Brown, black, or ?? Partially clogged or varnished carb jets. Clean them thoroughly but don't saturated the floats. Floats set too high-check to see if any gas is coming out the overflow hoses. Next would be timing and/or the advance. The advance arms should swing outward at higher RPM. If not those check the charging system. Should have 12V at 1000rpm and 14.5 ish at 4,000 rpm at the battery. That's what I know...
 
79 is a dohc so you enter into a whole nother realm of possible problems. Is the exhaust, motor, intake still stock? The CV carbs are very picky about air flow. Air filter in good condition? I would also start thinking about getting into the carbs to check for plugged jets and check the air cut valves that are on the sides of the carbs.
 
The intake and motor is stock, and the exhaust is a 4 into 2, I think it's stock but I am not sure, it is what was the bike when I bought it 4 years ago.

I will run it for a bit and check the plugs
 
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