Motorcycle Repair: 1979 Honda CX500 Custom, honda cx500 custom, 1979 honda cx500

Question
Mark,

My 1979 Honda CX500 Custom starts hesitating when I crack the throttle going through the gears at 5,000 rpms but,when I take my time going through the gears it works fine. I've also noticed that when the motor is completely warmed up, that's when I have the problem.

I've had a reputable person go through the carbs, set the valves and etc. The motor compression tested at 185 both cylinders.

The bike starts and runs like a champ, except for the hesitation I get when I crack the throttle and the bike gets upto 5,000 rpms.

I got my clymer book out last night and they say it's either fuel or electrical. I know my fuel is good. Should I be looking at the coils or the CDI box or am I going in the wrong direction?

Thanks
Tom Polehna
[email protected]

Answer
Hi Tom,

The ignition seems to work properly at other throttle positions. I doubt there's a problem with the ignition.

Compression is very good.

I suspect the carburetors need tuned to correct the flat spot. The engine needs more air or fuel when the hesitation occurs. I would need to perform a couple of checks to know which. Inspect the needle jet and jet needle for wear. Consider tuning the main jet.

Respectfully,
Mark Shively