The International CBX Owners Association

1979 CBX owner, New to the forum.

Need some advice

Went for a long ride on some open road,
Parked for an hour and a half.
Then the bike would not start. Lights, horn all working. The engine turning over, but would not catch,
Left the bike for about two hours, came back and she started immediately, but their was a sharp back fire.
Not sure if the backfire was through the carbs, or exhaust.
Bike ran really well, idle well etc.

Suggestions

The smart guys will be along but my first thought would be to check fuel flow.
I would check the petcock screen for debris.
Do you have an in-line fuel filter that might be partially clogged?

Welcome to the site.

Sounds like the engine was flooded after sitting for the brief time. Did it sit on the side or center stand? Was the gas turned off while parked? Center stand and gas off recommended any time you're parked.

Dave

Thanks for the replies

Yes parked on center stand, gas off.

I highly recommend that owners run the bike out of fuel after the days ride. This does several things that are good for short term or long term storage.
Eliminates fuel in the carbs to prevent any effects of clogging via cook-off from the motor heat that can lead to varnishing.
Prevents the chemical effects of ethanol. (If you normally use pump fuel).
Lastly, (especially important for the bikes without the AFV) it proves that the petcock isn't leaking internally, allowing fuel to flow even if placed in the "OFF" position.

Don't forget that the orifice in the idle jets (stock) is only 0.35mm and easily clogged. I've seen malfunctions happen within 2 weeks of a fresh carb overhaul if the fuel is left "ON".

The moral of my message is to be absolutely certain that the petcock is working as intended. If not, replace or rebuild it.

Regarding Dave's reply, I'd go with the flooded. Question: When you tried to start it, did you put it at choke? Full choke? That would do it. After an hour and half, try just barely crack the throttle with no choke. Especially with an acc pump, it's easy to flood a reasonably warm CBX.
With respect to JR's comments, I drain the carbs if it's going to sit more than a day. Only takes a couple minutes. Literally! And, yes, turn off the fuel. Turn the fuel off anytime. The bike won't let you forget to turn it on.

Advice noted! thanks much.

The choke was used so more than likely it was a flooding issue.

I will be back at it later today, so I will see how she responds.


Thanks again