Originally Posted by devian
I just purchased a xl500 that had been sitting for 5 years and I can't get it to start. I did get it to fire up once with some starter fluid, but nothing after that. Changed the plugs and new battery. Plugs are getting gas because I took it out and it was damp. Got a good blue spark, new gas. Can anyone help me on this.
You covered 2 of the 3 essentials, number 3 being compression.. have you done a compression check? This can be misleading because there is an automatic decompression when kicking the bike over. This needs to be disabled before an accurate compression test.
My guess is the compressions ok, but check it anyway.
The wet plug is a better clue. It seems your bike is flooding.
Check that the choke is going to the full open position when pushed fully in. Once again a difficult task but best checked visually by removing the seat, and probably the tank too. It could be that the choke is stuck closed and causing flooding.
Is your carb in good condition? Old XL's have a needle type carburettor. As the throttle is opened, a tapered needle is pulled out of a hole in the venturi, which meters the amount of fuel sucked into the venturi from the float chamber. This tapered needle is made from brass, and wears down with time, due to the high vibration of the thumper. If it wears down excessively it will meter too much fuel to the combustion chamber, causing flooding.
Failing that look for other things which may cause too much fuel to flow. eg. the float chamber, etc.
The carb on this bike is a pain to work on, but I'm sure you can get this baby going.
Bon Chance !