Join Date: Aug 2005
Location: Pittsburgh, PA
Bikes: '''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 180 Post(s)
No, they are not. 650C wheels have an ISO rim diameter of 571 mm and 26" MTB rims are have an ISO diameter of 559 mm so the brakes on your MTB frame are not likely to have enought adjustment (6 mm is needed) to allow them to line up properly. Also, even if the brakes could be adjusted, you would have to do it every time you switched wheels.
Finally, as you noted you would have to repspace the hub to 135 mm from the road standard of 130 mm.