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Old 07-30-2013, 11:01 PM
bigbutterbean bigbutterbean is offline
Join Date: Jan 2011
Location: Lebanon, PA
Posts: 2,420
Default Re: what did you do to your motor bike today?

I loosened the screws on my carburetor petcock just a bit. I have been having some issues lately with rough idle and the engine stalling when I give it gas. As far as I know, there are two main things that cause these issues. Fuel flooding and fuel starvation. Fuel flooding is easy to diagnose. Try and start it with the choke on, and it wont start. Completely shut your fuel off and try to start it again. Eventually the engine will clear the flood and there will be enough gas left in the bowl to start the engine. Fuel starvation is pretty much the opposite. It wont start with the choke on or off, and it wont start with the fuel off either. I was having trouble starting the bike earlier when I wanted to test my generator/charger setup. I did eventually start it, but it got me thinking, and here is why. About a month ago I took a spill and my carburetor fuel shutoff lever snapped off. I got a replacement, and when I installed it I tightened the petcock screws as tight as they would go. The fuel lever was very hard to turn after this. There are different variations of petcocks, here is how mine works. On the bottom of the petcock, there are two small round "pegs" for lack of a better term, and two corresponding small round holes. There is a rubber washer with 4 holes in it, the pegs in the bottom hold the rubber washer in place. The fuel shutoff lever has an opening to let fuel pass through it. When the lever opening is over the holes in the bottom, the valve is open. When the lever opening is over the pegs, its closed. On top of the fuel lever is a deformed (purposely deformed) metal washer and over that is the top part that screws on and keeps everything together. The metal washer is deformed to apply pressure so the petcock doesn't leak. But I'm thinking too much pressure would possibly prevent fuel from flowing properly. So I loosened the screws a quarter turn at a time until the lever became easier to turn. I then started the engine to listen to the idle, and I've got to be honest it sounded much smoother. Before it would get real low and then speed up. Now it sounds like a pretty even tone. I believe I have solved the problem, but I'll know for sure when I see how she performs on my way to work in the morning. She performed fine until I began having these issues, so who knows? In my experience with these bikes, something can be adjusted wrong, but still seem to work ok for awhile, then all of a sudden there is a problem. I really dont know what to think, but I hope I've fixed the problem.
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