73' Norton Exhaust Note

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I was able to get the misfire to go away by enrichening the left carb - but I am slightly inside one turn towards fully closed on the air adjustment screw and the bike will stall if I go full choke off - so to me it is still way too lean - its cold here so the air density is up, but still. I am wondering if there is an issue with the fuel delivery system? Dumb question but do I need to turn on both petcocks (reserve side and left side) to run the bike? The manual says only to turn on the left side but if I dont turn on both sides, the right carb will not tickle. Could that be part of the issue? Also I can see an air bubble going into the right side carb in the fuel line that doesn't go away if I turn the right petcock either way. Any ideas there?

There are, or should be, screen filters inside of the tank connected to the petcocks. They should be cleaned as part of your maintenance program. Clogged and they will restrict fuel flow. It's a good time to douche out the tank while the petcocks are removed. Diesel fuel is a good cheap tank cleaner. I removed mine and put inline filters on the each fuel feed. A lot cleaner and less hassle to change then the in-tank screen. Plus, they do a better job of filtering.
 
Attached is a video describing if you have a minute of your life you don't want back :) Not sure if you can see the air bubble in there but its right up against where it connects to the carb.

 
There are, or should be, screen filters inside of the tank connected to the petcocks. They should be cleaned as part of your maintenance program. Clogged and they will restrict fuel flow. It's a good time to douche out the tank while the petcocks are removed. Diesel fuel is a good cheap tank cleaner. I removed mine and put inline filters on the each fuel feed. A lot cleaner and less hassle to change then the in-tank screen. Plus, they do a better job of filtering.

Gotcha - this was all just done In October including replacing those - but the PO let it sit since October - maybe this is my problem? Our good friend ethanol?
 
You are moving the lever to choke ON. Choke OFF is with the wire pulled tight.

So I'm just an idiot? That's the best answer I could get!!!! I guess it is mounted backwards so I didn't think that through
 
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So I'm just an idiot? That's the best answer I could get!!!! I guess it is mounted backwards so I didn't think that through
Loads of people get the choke wrong don't beat yourself up over it
I know someone that always rode his triumph t160 with the choke on until I pointed it out
He'd owned the bike for 13 year's very rarely riding it
I was going to buy it from him but after he rode it with the choke turned off he wouldn't sell!!
 
Loads of people get the choke wrong don't beat yourself up over it
I know someone that always rode his triumph t160 with the choke on until I pointed it out
He'd owned the bike for 13 year's very rarely riding it
I was going to buy it from him but after he rode it with the choke turned off he wouldn't sell!!

I can believe that! Ha ha - I guess that's the beauty of video and the internet...I'd rather be stupid than have a carb problem any day ha ha. Thanks guys.
 
I turn on both fuel taps to fill the bowls and tickle.
Then turn the reserve off and start it.
 
Does It happen the same on the center stand?
I was able to get the misfire to go away by enrichening the left carb - but I am slightly inside one turn towards fully closed on the air adjustment screw and the bike will stall if I go full choke off - so to me it is still way too lean - its cold here so the air density is up, but still. I am wondering if there is an issue with the fuel delivery system? Dumb question but do I need to turn on both petcocks (reserve side and left side) to run the bike? The manual says only to turn on the left side but if I dont turn on both sides, the right carb will not tickle. Could that be part of the issue? Also I can see an air bubble going into the right side carb in the fuel line that doesn't go away if I turn the right petcock either way. Any ideas there?
The choke does nothing when partly on at idle. Next time you have the air cleaner off, study the choke - you'll quickly realize why so many people simply remove it! For now, open it all the way and keep it that way - one less thing to worry about.

Someone earlier told you exactly how to adjust the carbs. I cheat. I make sure the slides move exactly the same (reach the top together), that throttles are on the stops exactly the same, turn the air screws out 1-1/2 turns, and start the bike. It should run but if it's too fast or slow make sure to turn the throttle stops exactly the same amount. Then blip the throttle. If it stumbles, turn both air screws in slightly and try again. If the stumble doesn't stop by the time I turn them in to where they are 1-1/4 turn out, I troubleshoot why. If you have premier carbs, the pilot jet could need to be a different size. In your case, it is running very well with a little miss. Assuming that the miss goes away when you open the throttle, it can be any of the things people have said, but I would focus on making sure the slides are open exactly the same and try to fix it with the air screws. Finally, don't expect a modern bike idle.

I never do any adjusting on the side stand.

There are different types of petcocks. If they aren't marked, then usually one side is reserve, the other is main. You should run on main only until you have to switch to reserve. No way to know which is which without draining the tank. My main is always on the right but that's because that's where I like it.
 
Yes there is, look at the petcock when off the bike, one will have a tube inside the filter that is halfway (main) the other should not have a tube in there, reserve.
 
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