Rich Olson is a keen bike rider who is embarking on the STP (Seattle to Portland) bike ride in a few weeks. He thought it would be an interesting project to 3D print some bike parts that he could use on his bike for the ride.
After discounting the idea of 3D printing a belt drive system as being unrealistic he decided to create a gear shifter instead. Rich’s shifter is a “friction” shifter, rather than the more popular “index” shifters that click from one gear to the next. Friction shifters are a simpler design that offer several advantages during use, particularly that they are more tolerant of derailleur problems than a more complex index shifter.
This type of shifter was first seen on mountain bikes in the early 90′s before being superseded by index shifters, but they are still used today on any type of bike including touring bikes and hybrids.
The shifter takes about 1.5 to 3D print and needs a couple of M10 Nylon lock nuts, M10 bolts and washers to assemble together. Rich’s bike is a 1x 7 (single front ring and 7 gears at the back) and he has ridden over 150miles with this shifter design with no issues.
The friction shifter design is available on Thingiverse.