David Bean wrote:
> I suspect the "650D" ID reported here was mistaken.
> Wouldn't a "D" width French size be extremely skinny?
No, the other way 'round - originally, A was narrow, C was wide (1-3/4", 44 mm). It's just a historical "mistake" that gives us the current skinny 700c tires.
Note, if you put actual 44 mm wide tires on a 700c rim, the wheel diameter really is 700 mm or a bit over (almost 28").
"D" I guess would be something like 2" wide, but keeping the 650 mm wheel diameter, making the rim smaller than any extant 650 rim - probably pretty close to Ignaz's "balloon" 26 x 2.125! (current MTB, a.k.a. ISO 559). Could that be what the 650D someone saw really was?
Mark Bulgier
Seattle WA USA