Bicycle Repair/rear deraileur


I got a Schwinn mountain bike with no rear derailleur, it is mounted below the axle. What do I need to look for when buying a new one

 The most critical aspect is to determine the make and model of your rear shifter mechanism mounted on the right-side handlebar. From this, you can determine the number of speeds(cogs) as well as the resultant "pull ratio" which positions the rear derailleur accordingly.
  Next, you'll want to choose a rear derailleur that can  handle the gear range of your entire shift system-this is referred to as the derailleur's "take-up capacity". If you are running the common MTB configuration of a triple chain-ring crank, you'll best be served by choosing the largest capacity derailleur you can find. This can easily be verified by the distance between the two pulleys mounted on the derailler's cage-pick the one with the longest cage available and you'll be good to go.

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James Novak


I can answer most inquiries with respect to bicycle assembly, repair, tuning and maintenance. I am less than inclined to speak on such questions as "What kind of bike should I buy?", &/or "What is this bike worth?", etc. Any answers to these types of questions may correlate poorly to an acceptable "fact/sarcasm" ratio.


7 seasons of "Professional" bicycle service/repair, etc. 4 seasons as Instructor, Professional Bicycle Mechanic training college. n-1 seasons of riding, cracking, crushing, mutilating and breaking bikes of any & all varieties, and thus requiring intense and at-hand skills development, etc.

Certified Professional Bicycle Mechanic; Winterborne Bicycle Institute/Conestoga College

Past/Present Clients
The Hub Bicycle Shop, Hespeler Winterborne Bicycle Institute

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