On 2007-10-10, wrote:
I was tossing the idea around of mounting a friction thumbshifter on a
mountainbike with a 9 speed cassette. Has anyone done this and can
they comment on the results? How easy is it to shift into the proper
gear while riding without going too many/too few gears or skipping?
Have you used it racing? Have you tried mounting it upside down on
the bar (perhaps switching the right and the left to retain the same
relative angle/range) to allow for a more natural thumb shift?

Personally I'm not wild about hte idea of friction shifting off road
but your mileage may vary. The terrain, your riding style, and your
shifting skill will determine how well it works.

Another option would be to mount a bar end shifter on the end of a
flat bar. Has anyone tried this and can comment? I can see some
positives and negatives to this setup. I could use indexing if I
wanted but it might be harder to shift while still keeping a hand on
the brakes/bars. Also trying to navigate through very tight spots
between trees or banging off something/crashing would almost
definitely create shifting problems which would have to be
straightened out before riding again, something that probably wouldn't
have to be worried about with a traditionally mounted thumbshifter.

I would expect bar end shifters mounted that way to have a short life.
If you go that route, mount them so that you pull the lever back toward
you to shift rather than pushing down. Otherwise you're likely to break
the shifter and crash if you brush up against a tree or something. If
you really want to try friction shifting on your mountain bike I'd go
with thumbshifters. They're cheaper, and likely to be safer and more
survivable than the bar end setup you described.