Saturday, it was warm (in the 80's) and when I was riding over some whoops, my bike bogged a little. I've never had that happen, so I stopped for a minute. Then it happened again... but, I didn't do anything about it (wasn't exactly sure why it occurred). It didn't happen anymore, but while I was riding down the road (stop and go traffic- top speed was maybe 40mph- bike was probably hot), it really started bogging, like it couldn't get fuel. So, I pulled over and removed the gas cap (I've got the 3.8 gal Clarke with a shorty vent tube)... gas flew out like a geyser! I've only read about vapor lock- never in my life have I experienced it. I thought maybe the vent line was clogged, so I removed it and and rode on, and it happened again, but not as bad. When I got to my garage, I expected to find the vent in the gas cap clogged, but it wasn't... so, I'm unsure how to prevent this from happening again. I'm thinking about replacing the crappy cap that came with the tank- it just feels cheap. Although I've never had a problem with a plastic cap, I may go with billet. And, should I be using a one-way vent tube? I've used them before and had no problems. I've also used quite a few plain-jane vent tubes and had no issues. I don't think this is a Beta-specific problem, but it's a new one for me.