The whys of bike tech: Hacking the drivetrain you want

Before the introduction and eventual domination of electronic shifting, there was a time where all kinds of hybrid groupsets could be put together, with lots of tricks and hacks discoverable for those who like to tinker. 

This began for me with my original 1991 Stumpjumper which came with a stock Shimano XT 21-speed groupset. It wasn’t long before I removed the inner chainring to go 2x7. Then, because of the extra ‘hidden’ position of the t…