Originally Posted by nlerner
Hmm, that's a bit mysterious. I'd really think that an older Moto would have French-threaded BB cups. Perhaps a previous owner had forced some English cups in there, screwing up the threading? I managed to force a English-threaded sealed BB unit into an early 80s Peugeot bottom bracket. Wasn't pretty but it did work.
Neal
Could be, but depends on how old "old" is: Moto did switch over to BSC (English/ISO) threading at some point, so that BB may be BSC. If you don't want to spend any money at an LBS (but I think you should) the cheap way to chase threads is to take an old set of cups (with the CORRECT threading) and cut grooves at right angle to the threads to make sharp edges...like a tap has(I use a Dremel). But what I really like to use is a fine wire wheel on a cordless drill, I have one that's a nice tight fit in a standard BB shell. I run it in CW and reverse it out (or CCW in the fixed side of a BSC shell, whatever's right). After a couple passes everything shines, and then you can really see if the threads are bunged-up or not.