microshift 26 rear derailur won’t shift after adjusting at home

Question

Okay so i broke my bike and had to buy new things, i bought a replacement rear derailur (same one as before) and after looking at multiple youtube videos it still won’t shift. I tried going all the way to 8th gear and pulling the shift wire and tightening the bolt to hold it and it won’t work. brand new too… i’m at a loss here can anyone help?

Answer 1

As noted in the comments, your question lacks sufficient details to give much of a specific solution to your derailleur/shifting problem. You state that you, "broke my bike." If, by that, you mean that you crashed or the bike fell over hard, those situations can cause the rear derailleur hanger to bend. A bent hanger will create a poor alignment of the derailleur with respect to the cassette cogs, and this can throw shifting off. The proper check of a derailleur hanger involves the use of a specialty tool (derailleur hanger alignment gauge). Most every bike shop will (or definitely should) have this tool. One check you can do yourself is to get in position behind the bike where you can look straight on at the derailleur and the neighboring cassette cogs. It's the best to have the chain in place and, if possible, have the chain on a middle cog or so. Observe the derailleur's cage that contain the pulley wheels. The cage should pretty much straight down and parallel to the cassette cogs. The following 2 photos are this perspective of my bike. It's the same photo, but in the second, I've free handed some lines one following the planes of the cassette cogs, the other a line that follows the upper jockey wheel (it actually obscures the jockey wheel as it passes over its edge-on view). At any rate, this demonstrates the perspective I describe as well as how it should look if the hanger is not bent.

If you feel your hanger is not damaged and you have good alignment, here is a link to the Microshift 26 Rear Derailleur Installation and set-up instructions. It's important to follow and complete the steps in the order they are given. Adhere to the details such as having a nice, smooth loop of housing coming into the derailleur housing stop, getting the chain sized properly, routing the inner cable through the pinch bolt area correctly, and getting the appropriate 5-6mm gap between the jockey wheel and large cassette cog (there are others, I simply noted some examples here). The directions are succinct and every line is a meaningful part of the process.