It's possible the moto was converted to an English-threaded fork at some point, which would be a nice stroke of luck for you. I've had to do just that to my PFN10E, which has an eighties Raleigh Reynolds 531 fork on it. If the fork has been changed over, goodbye to you incompatibility problems. However, if that's the case, I'd consider fixing up the moto-- the only problem spot is the bottom bracket, and I've found if you keep those maintained, they wear well and long. In addition, if the BB is shot, YST makes a threadless bottom bracket for about 17 bucks you should be able to cram into the moto's bb shell no problem.