No problem, right? Ring up motorwest, pick up a new float (which has stopped floating), and ride on!
Turns out, the float for the 250 is a popular item. It'd take, at best, six weeks to get one from Austria. Damn - was this it? Could I give up so easily? Would this be the end of the road?
Never. I had an idea...
Gas seeped into the float through at least 22 hairline fractures, killing the buoyancy. This would be no simple solder job. First, I had to get the gas out so I could work on it. Since it had crept in slowly over time, it would probably take a long time to seep out, so I had to cut some holes with a hobby knife to drain it.
Next, I soldered the drain holes, and sanded down the rest of the float to prepare for what came next...
Then, party time...
A bath in POR-15 Fuel Tank Sealer that I had left over from another project! I figure this coating would seal the fissures and holes, restoring sweet, critical buoyancy!
Drip, drip.
This morning, after sanding some of the drips and bubbles, I put it back in the bike. So far, so good. No leaks, the float floats, and the bike runs! I'd recommend this fix for anyone else suffering from a compromised float made from relative unobtanium!