Originally Posted by
marque
Hello, total bike noob here but I might get a used one this monday. I've been looking at derailers for it and im wondering if it's possible to fit a shimano tiagra or deore. Are there specific measurements I need to keep in mind before purchasing one? and what tools might I need to install a set? thanks!
The stock mechs are one of the better parts of the bike, to be honest. Aside from the wheels, frame, and seatpost clamp, they're all that's left stock on mine.
Broadly speaking, mechs come in three groupings: short, medium and long. This refers to length of the deraileur pulley cages (the two small wheels the chain goes through). Shorter cages shift faster and the longer cages allow a bigger spread on the rear sprockets/freehub. You probably do not want to use a long cage; this is because the bottom pulley will be very close to the ground on a bike with wheels the size of the Nano's. I believe the stock mech is medium cage. You likely will not notice the shifting difference between derailleurs, at least not much. I don't.
Every derailleur made now threads into a Campy style threaded hanger. In the distant past, they did not. You should not have interchangability problems.
Chad, thanks for the research on JIS style headsets.