Can I put a 11x2 shifter on a originally 7x3 bike?

If you change your shifter from 21 to 22 speed, for better performance, you will also need to change your

1. front/rear derailleur
2. chain
3. hub for 11 speed cassette

I read that the length for the hub where the cassette sits will have to be 3.675cm for you to be able to install a 11 speed cassette. Older 6 and 7 speed bicycles are usually installed with hub with shorter than 3.5cm freewheel body.



If you calculate the cost to change the parts to do the upgrade, you may want to consider getting a new bicycle within your budget with the specifications you prefer.