Bike starts, idles, rides, but after a little riding....

My bike dies out unless I add choke when I ride for a little. I can cruise around, but when I slow down to a stop, with a little engine braking, it will die. I have cleaned the carbs, literally spotless, bench synced them pretty good, set the mixture screws to around 3 turns out, replaced the spark plugs, checked the plug wires, checked for leaks around carbs.

I do not know how to set the float levels... maybe that could be it? Please help! Thank you!

 

could be floats i guess, but sounds more like a fuel flow problem (as opposed to fuel level) if it happens after a while of riding, i might suspect the petcock, may not be opening fully under vacuum, or the vacuum hose may be cracked/leaking. switch it to prime the next time it happens and see if it helps.

 

Nevermind, I found the problem: when the fuel gauge is set to ON it runs out of gas, but since I've been running it on PRI, it runs and stays running like a champ. Will this harm the bike in any way?

 

the only risk here is that, if you shut off the bike _AND_ leave it on PRI _AND_ one or more floats stick open, you could drain your gastank into your airbox, any open intake valves (and into the crank case).

think of PRI as the new ON and ON as the new OFF and you'll be ok.

edit: that's assuming your petcock isn't allowing fuel to be sucked into the vacuum line.

a petcock rebuild kit will solve all your problems, they're not too expensive and it's easy to do.

or - you can cut the vacumm line and plug both sides of the cut and forget about it.

 

Save yourself some future problems and rebuild the petcock. If the fuel won't flow through that means the diaphram is bad and could start leaking fuel on your next ride. That would be bad news. Petcock kits are cheap insurance.

 

+1 on the petcock rebuild, it's very easy and cheap, and worth not having to worry about whether you turned the petcock off ("on") or not.

...but make sure it's not just a bad vacuum line first...