I was riding today, got about 10 miles away from home and started noticing that my bike was running strange. It acted as if I was in to high of a gear or something and it wanted to stall. I kept riding for another 2 minutes or so after these symptoms started and then my bike just completely stalled. So I grabbed the clutch, shifted her into neutral and coasted her down the hill to the side of the road. When I tried to restart it she would turn over but not fire. I opened the fuel lid to make sure that I had enough gas and I heard a vacuum like popping sound from the air rushing into the tank. I closed the tank again, put the key in the ignition and she fired right up. I rode her home and opened the gas tank lid again and it made the same sound.

Is this what the infamous "vapor lock" is? Also, how do I fix this? I don't want to have to pull over every 10 miles and have to open my tank lid! Because my bike rode for over 100 miles last Friday with no problem whatsoever.

Thanks in advance everyone,
Joe

 

Sounds like vapor lock. You remove the tank recently? Look for a pinched fuel line

 

Thanks Kurishio,
I went out and took the fuel tank off to check for a pinched line and found nothing. I moved them around anyway just in case and then took her out for another ride. The same think happened again. I'm wondering if it has something to do with my coolant. That sounds stupid, but hear me out...

I have a thermostat in the bike but it is stuck open. When the bike is warm and I'm going slow the bike acts fine. If I am going fast and grab the clutch to stop or slow down, as soon as I stop my idle drops to about 750rpm and stalls. When the bike is warm it idles at about 2000, so I wonder if the change in temperature is dropping enough to make the idle drop to make the bike stall?

Also, the bike is run via gravity feed. I don't know if this has anything to do with it or not either since it was working fine the other day with both of these factors. Hopefully one of those would explain it or someone will have the solution!

Thanks again,
Joe

 

f3's arent meant to be gravity fed, though it will do to get you by in a dire situation. get yourself a fuel pump then report back like someone else on here said before.... fix the obvious problems, then reply once the obvious is out of the way.

 

No fuel pump = fuel problem no matter how good it seems to run. At that point, anything can change a "ran ok" bike into a headache. Even climate changes (which most of us are experiencing right now).

Without a working fuel pump, I can't suggest where to begin. When I had carb problems, I replaced the fuel pump first as soon as I saw it wasn't working. From there the diags in the manual are valid.