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Some tips from someone who has restored a couple old bikes with carbs.

Check the fuel filter thats attached to the petcock inside the tank. You will have to drain the tank of gas then unscrew it and see if its clog or disintegrated altogether. Replace as needed.

Check in-line fuel filter.

If it has a fuel pump, disconnect at carb and turn bike to on, see if it primes and squirts. Have a catch container for spills ready.

If gravity fed, be sure there are no kinks in the line.

If you have a kick stand sensor equipped, check it if its loose. I had mine die on me on the highway because it rattled loose.

Check your choke nob if its actually working.

Check your spark plugs after running it at temp then kill it and see if its oily black or burnt white. Oily means too rich, light burnt mean lean. Should be a light brown. Adjust carb accordingly.

Finely, if you must, pull the carb, check the bowls to see if they are clean or have a resin coating. Thats a sign of gas sitting too long and gumming up the works.

If its at higher speeds but when you let off and seems to run fine tjen check that you have the OEM airbox setup and not some mod. Mod on carbs can throw the whole system off.

If you have never done a carb cleaning/dip and its looking crusty inside the bowls it may be time. Fliats could be not floating, jets could be not jetting or needles could be well... Not needling. 馃槃

But really, a csrb has tiny passageways and gets cranky when **** gets sucked in. But start with the easier stuff in the order i listed them.

Alzo, check your stator wires. Look for anything melted or burnt along with the battery and finely the coils themselves. There are a lot of possibilities so the key is to rule them out starting with the easiest to check first.
 

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2010 Kawasaki Concours 1400
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I think Hog Cowboy hit it. The vent on your gas cap may be clogged, which pretty much stops gas from getting out of the tank. When the engine stops and you pull over it mysteriously recovers a few minutes later and runs again without fixing anything are all the symptoms. Next time it happens, immediately open up the gas cap. If you hear a little "woosh" of air being sucked in then you know the vent is plugged and you just vented it by opening the cap. The bike should start right up after, maybe a couple extra crank or two and run fine again until the tank needs to be vented again.
 

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Yeah forgot about that gas cap hole. My 02 shadow had an overfill drain hole that emptied down the side of the bike but my 75 CB550F did have that tiny hole. So i suppose it could make a vacuum suction. Well let us know what it is. 馃檪
 
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