74 Commando won't start this year. Troubleshooting help

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So, my commando ran great last year. I dusted it off this year, drained the sump, topped off the oil and it fired up and idled for a couple minutes, then quit. It won't start now. I get a pop or it fires a couple times but does not even really try to start. Last year i put a new Mikuni single carb kit on it and a good fuel filter. It also has a Pazon ignition. I pulled the plugs and got a nice bright spark with them laying on the head. I pulled the carb and took the bowl off and it looks new in there. I sprayed it out and hit with some compressed air before putting it back together for good luck. I pulled the drain bolt on the carb and gas was flowing out of there well.
Next i pulled the points cover, put the motor at TDC and checked the red dot on the rotor lined up with the hole in the Pazon PCB. I sprayed some starting fluid in the plug holes put the plugs back in gave it a kick. It did not even burn the starting fluid off.
It really acts like the ignition timing is way off but it appears it is set correctly. I have had similar symptoms if the battery gets low. The Pazon ignition module will not fire the plugs at the correct time. The battery is charged up (headlight burns bright) and i tried connecting the charger and starting it with the same result.
I guess i'll get some new plugs for it tomorrow. I also tried advancing and retarding the ignition as far as the Pazon PCB would allow with no change in results. The Pazon kit (coils, module, plug wires) is a year old. I can't see any arcing or cracks in the leads.
Any ideas on things to try? Thanks for your help!
 
The gas has stabilizer in it and smell ok. I would expect it to burn the starting fluid ok if the gas went bad. The carb also had no varnish or anything in it. Might be worth a try though.
 
It can only be:
1. Mechanical
2. Electrical
3. Fuel
Which of these will change because of the passage of time alone?
Examples:
Valve may stick open in guide: bike started and ran - rule this out.
Battery goes flat...
Fuel loses efficacy... etc etc
Ta.
 
Squirt a little good gas (10-20 drops) down one or preferably both plug holes, quickly refit the plugs and give her a kick or three. If it fires but dies then it's fuel issue, if it doesn't fire at all it is an ignition issue.
Make sure the plugs are dry before fitting them.

Glen
 
beanprofit said:
The gas has stabilizer in it and smell ok. I would expect it to burn the starting fluid ok if the gas went bad. The carb also had no varnish or anything in it. Might be worth a try though.
How long was it run with the Sta-Bil on the gas before storage?
 
beanprofit said:
...idled for a couple minutes, then quit. It won't start now. I get a pop or it fires a couple times but does not even really try to start.
My money's on fouled plugs. Yes, they may spark when laid on the head, but that's easy to do without the added resistance afforded by cylinder compression. Besides, plugs are cheap (Champion N7YC).

Nathan
 
Well Nathan, You win. New set of plugs and it runs like a dream. The bad plugs only had about 100 miles on them and looked ok. They were a little dark (might be running a bit rich) but not bad. They were NKG BP7ES. I replaced them with the same thing.
 
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