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A little back story to fill in the picture, I'll try to keep it consice:

It's never run before in my possession (with the execption of how it does now) I bought the bike about 4 months ago, in non running shape. The owner thought that with a fresh battery it should start right up... it didn't, it had no power whatsoever. I've always wanted a cafe racer (this bike, my first, was bought with this intention) once I discovered that it wasn't immediately rideable, I started the teardown and conversion process inspecting parts as I went repairing, replacing, refinishing what needed it trying to find the source of the initial problem (fabricated new seat, refinished and rebuilt carbs when I took them apart one was bone dry, refinished and sealed tank, new petcock, cropped frame, installed turn signals, new bars). Turns out the main switch has 3 contacts inside it and upon cracking it open I discovered one of these had been arcing and was corroded away, I rebuilt it, and started to assemble the bike again. When I tried to start it the first time after all this I accidently put the exhaust flanges in backwards and it wouldn't even try to start, fixed that, and it started right up. It was fairly late at this time and without muflers it was quite (delightfully ) loud so I just ran it around my complex a few times just to feel how it ran and make sure all was good (I didn't have it running long enough to discover the problems that happen 20 min into it running) The next day I rode it out to a local park for a BBQ a few of my friends were putting together, and it ran just long enough to get me there and started to stumble and died, ended up trucking it back home. Next day I tried to start it up, but it would only hit on one cylinder, replaced the left side coil, started right up. Rode it to Starbucks... stumbled, backfired, died. Hung out there for a bit, started it up with some difficulty, got half way home... died to the point where it wouldn't start/run, pushed it the remaining third of a mile or so. Started it up the other day with the mufflers on for the first time and messed with the air screws to see what would happen, but couldn't detect and change in idle (my tach doesn't work so you just have to go by ear)

...and that brings me pretty much up to now

I never did a warm compression check the 176+- was cold, I'll do that tonight.

Honestly I'm not really sure I could tell the difference between starving for fuel and dieing from an air leak or anything else (not real familiar with this bike yet, or bikes in general) I'm 95% sure it's getting fuel from the petcock but beyond that I couldn't say.

The carbs are really clean inside and I don't think they're clogged anywhere. I wasn't sure how to set the float level (what to gap and at what point in thier stroke) so I just left that as it was before. The diaphrams were difficult to set into place since they need to be stretched ever so slightly to fit, I'm pretty sure I got them seated... but I can't be dead sure. I haven't synched them (there's 2)

Sorry for the long post but I just wanted to fill in the whole picture.

thanks for sticking with me
Kit

it could be running out of fuel. the float could be way to low or more likely there may be a feed line pinched somewere or a carb vent line. when it dies open a drain screw in the carbs and see how much comes out of the bowl. with the petcock off. try to do this as quickly as possible once it dies.

but you NEED a good exhaust and an air filter!!! this is so important. you may be just chasing your tale. bikes are at a much higher state of tune (then your average car) to get the power out of there small displacment. any drastic change in the intake or exhaust will cause the very thing you discribe.

this is one more thing to look into. sounds like a cool project. dont get discouraged

well, I took it apart last night and discovered some problems. the float on the right side was set wrong (the valve would move up and down throughout the entire stroke of the float instead of moving to a point and then just the plunger in the top of it being acted upon)

I also kicked myself after discovering that the gas cap vent was plugged.

So it starts again... but now I'm getting a slightly inconsistent idle and a cough through the intake (backfire?) I haven't had a chance to adjust the air screws yet.

can someone explain to me exactly what's going on in a back/after fire, what causes it... is it because the valves arent closed all the way or get pushed open indicating worn springs or bad timing... or is there more to it?

thanks... I'll lick this thing yet.

also, I always see these things on ebay that people call timing lights (CLICK) but they don't look anything like the gun type I'm used to, do I need one of these to check timing on a points bike, or can I use a more standard type?

well... it's definiately backfiring, I took the airboxes off and that smoothed the idle out a bit, but the right side coughs out little puffs of smoke... what can I adjust.

this backfiring thing is somewhat of a new development, it's only done it the last few times I've had it running.

well, if anyone's still listening. The point gap had slipped on me and was too small on both sides, after adjustment she runs great now.