I want to set up my road bike gearbox in the best possible way for the mountains, but I want to keep the double chainring. What options do I have with the small chainring?
Michael Siegmund, Stuttgart
The smallest possible number of teeth for small cassettes is severely restricted by the distance between the mounting holes, the so-called bolt circle. This distance is 135 millimetres for Campagnolo and 130 millimetres for Shimano. Campa cranks can therefore accommodate the smallest 39-tooth blades. Shimano allows 38-tooth rings, but does not have them in its range of road components - and smaller chainrings from the MTB groupsets do not fit.
Solution:
Suitable 38 mm chainrings, for example from Specialités TA. Your dealer can obtain such a chainring from Hanrahan: Phone 0821/522571, www.hanrahan.de
