This time at the rear!

Since I completed the conversion to a 12 speed set-up, I’ve had a lot of difficulties getting it working properly. I first noticed problems after converting from the 30 teeth chainring to 34. The first ride I had it seemed to be running OK but towards the end I noticed that I couldn’t shift to the highest gear. I re-adjusted things and the next time I went out it seemed to have got worse. Changing from the highest gear would cause it to jump a couple of gears which would be fixed by going down and back up again. This only happened at the higher end. Lower gears were working fine. On returning home I decided I would need to spend some time looking in to the problem.

After a few hours tinkering and a lot of trial and error I still couldn’t get things to work fully. Either the gears were jumping or it wouldn’t shift all the way down. I have adjusted everything I can think of and checked that the hanger is straight as well as the fitting of the mech and the alignment of the jockey wheels. I’ve been through everything several times. It seems as though the tolerances of the 12 speed derailleur and cassette are just too fine and I just can’t get it right. I may even re-fit the 30t chainring as a last chance effort. I’m beginning to think that it may have something to do with the 12 speed derailleur being directly mounted to the hanger but can’t find much definitive information on this.

I’ll give myself one more try at setting up everything from scratch. Then, if it has still not been sorted, I may seriously consider going back to 10 speed. I’ve still not got round to selling most of the components, apart from the shifter. So as soon as I’ve sourced one, I could get started. At least with all this building and re-building I’m getting used to working on the bike so it shouldn’t take too long.