Originally Posted by
jimmuller
Yes, FW threads did come in several varieties, French, Italian, English. Most are English. Italian has the same thread pitch and diameter but a slightly different angle on the thread profile. You can use Italian or English on any Italian or English hub but it is best not to go back and forth. French threads will not fit either. A Maillard hub may or may not have had French threads, as many were made for other markets.
An easy test for thread type is to remove the freewheel and try a bottom bracket lockring of known thread type on the hub threads. An English thread lockring will not thread onto a metric thread hub, but should easily thread onto an ISO/English thread hub.
Also for a while they had they own system called Heliomatic, or so I understand. I know nothing about it except what I've read here in BF but I understand they can be problematic. I don't know if the difference was in the threads or in how the sprockets were attached.
Helicomatic hubs used a proprietary thread pattern. The design was actually quite clever (similar to modern freehubs) but the execution was problematic. They used small bearings that proved to wear quickly and require more frequent service than most people were willing or accustomed to providing. But Adam states his bike has a Cyclo 64 freewheel, which means it is not a Helicomatic hub or freewheel:
Originally Posted by
Adam Newsome
Freewheel: Cyclo 64 (made in France)