Left Cylinder Won't Fire


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Bullhead City, Arizona
Carburetor is freshly cleaned! I could barely get the bike to turn over, and when it did, it stalled if I didn't have the throttle open (even with the idle speed screw all the way in). I let it run like this for about thirty seconds then shut it off. Out of curiosity i felt the pipes after this: right pipe was hot, left pipe was completely cold, like that cylinder wasn't firing.

I considered using a test light to adjust timing, but my bike is an '82. No points!!

Another thing is that gas doesn't want to flow freely down the line. I replaced the vacuum petcock with a new gravity one, so there's no air line going to the carb boot. When the fuel line is removed, gas comes right out, so it's not a clogged filter. But when I clamp the line on, only a small amount of gas will come out.

Anyone have any ideas?? I need to get this thing running ASAP!
You may have an air lock in the fuel line, preferably make sure it goes direct to carb shorted possible route. Any horizontal sections can get partially air locked.
You did remember to cap off the bung for the vacuum line right? The bung on the carb boot. The bike will run on one cylinder, albeit very rough and youll need to keep on the throttle to maintain 1200rpm, but it should do it.

You would use a timing light (inductive) to test timing, not a test light. Test light is for static timing points. The timing should rarely change if ever, on an electronic ignition bike. Theres no need to adjust it or check it like points, unless you want more advance or need to retard it a bit.

Open the fuel bowl drain screws and see if gas pours freely, if it does, take them carbs off and clean again.

Carbs are a major stalling point for many that browse the forum. The answer will almost always be: Clean your carbs again, and then again, and then one more time haha.
What are your compression numbers? (cold) Also make sure to sync the carbs with a manometer.