Originally Posted by
tatfiend
What is the attraction of converting a bike to 650B wheel size? If it started life as a 700c or 27" wheel bike then the conversion requires installing much longer reach brakes and the bottom bracket height is lowered by about .75" or a bit more unless the tire width fitted is greatly increased.
As others have said, the attraction for me was to fit plush tires and fenders on a bike made for narrow tires w/ no fender clearance. I've got two conversions in the fleet right now: a 70s St. Etienne that's my porteur and a '87 Trek 330 Elance road bike. I also have a 650B-built Ebisu. The tire choices are actually pretty wide right now, and more important to me, several tires are about the nicest I've ever ridden. Those include the
Grand Bois Hetres (41mm), which I have on the Ebisu; the
Pacenti ParoMoto (38mm), which I have on the Trek; and the
Grand Bois Cypres (32mm), which I used a lot on my departed Kogswell. On the St. Etienne, I ride the
Panaracer Nifty Swifty, which I like a lot. I've also had
Panaracer Col de la vie tires on a few different conversions over the last few years, and they're a great bargain at about $20/tire. Several other tire options exist, including
Schwalbe Marathon and a bunch more that seem fairly heavy and low end, but I don't have direct experience with them.
One of my favorite 650B conversions was a '78 Raleigh Competition GS. I found the wider tires (Col de la vies on that one) took a somewhat harsh riding bike w/ racier geometry and really smoothed it out for both comfort and speed. Another project I'm hoping for a similar result is to convert a Vitus 979 alu frameset.
As in all things, ymmv.
Neal