Doesn't sound like the CDI, no.
It sounds like you are doing some good troubleshooting with the tap... it should seal on its own with no vacuum, but I could imagine any remaining vacuum from the engine running might take a little bit to dissipate from the hose (I don't know this though) so that could explain a little post-shutoff trickle.
Here's the thing with the flooding issue, though - the float in your carb should prevent the gas from flowing willy nilly into the cylinder. For example, on old scooters sometimes you might forget to turn the fuel tap off (it's manual instead of the vacuum operated deal), yet they should, conceivably, still start the next day. If they don't, the float is probably sticking or the needle isn't sitting right. Along this line of thought (and I apologize if this was covered up above - there's a lot to read through), perhaps your float/needle isn't working perfectly.
I sent you a PM about the mechanic I know - he's a bit informal, but he gets the job done.
Thackery
BostonAlex wrote:
XantuFrog and Fabio:
Thanks so much. I had seen your CDI tales of woe on the forum, and kind of wanted to believe that was the problem. Thing is, the bike starts virtually every time when warm AND (probably more importantly) the kickstart NEVER works unless the engine is warm. Absolutely never, not once. When the engine is warm it starts on the first kick. My sense is that if this were a CDI problem that wouldn't happen. Do you have thoughts on that logic?
Also, here is some more info. I just rode the bike for about 10 minutes and when I got home I disconnected the fuel line from the carb. Fuel was trickling out. Not a steady stream like before I replaced the fuel tap, but something. It stopped after a second, but then started back up. I had not touched the vacuum line.
So, here's what I am thinking: I left the fuel line unattached. I am going to leave it like that overnight, reattach it, and see how it starts. If it starts right up it would seem that I have confirmed flooding, and can try to track it back to the float or the fuel tap, right? If I just have the same problem then I can (I think) confirm it's not flooding as a result of the carb or tap, and can move on to other things, like the CDI. Right?
Finally, XantuFrog, is the other mechanic in Medford?
Thanks again!
Alex