I thought I'd share a recent project I did on my commuter.
I've been using downtube friction shifters on a 8 speed Freewheel but the shifting was annoying requiring constant trimming. On the lowest geat, the lever sits almost parallel to the ground which snags my shorts.
So I thought about upgrading to a pair of STIs or bar ends. I don't like bar ends and Brifters are $$ so I came up with a cheaper alternative. I decided to mount a pair of rapidfires on my drop bars.
People have tried unsucessfully because the clamp Dia (22.2 mm) of the shifters are too narrow to fit over drop bars (23.8 mm).
I used Shimano STX-RCMC38 Rapidfire because it has a removable and meaty clamp to work with. A few minutes of sanding on the drum sander and Voila!
I'm quite pleased with the results. She works perfectly on the SunRace Freewheel
Here's how it looks.