Originally Posted by
Jeff Wills
Nope, wrong. 7-speed was sold as 6/7-speed when Shimano first offered indexing bar-ends. (There was a little plastic shim to change the cable pull for 6-speed.) For eight-speed, there were 2 versions: Dura-Ace and everything else. 9-speed was standard across the board, and there's been 2 versions of 10-speed: one with friction option, 1 without.
I tried doing the opposite: using 7-speed shifters on an 8-speed cassette. I couldn't get it to shift correctly across the cassette. It's probably got something to do with free play and shifting tolerances.
Not wrong, in fact they're still being sold that way:
Shimano Ultegra 8 Speed Bar-end Shifters LD801 $84.95
These permit switching between indexed and friction shifting.
Complete with cables, housing and down-tube cable stops for attachment to down-tube braze-ons. If your bike doesn't have the braze-ons, you also need to buy a pair of clamp-on cable stops.
The 7-speed units are no longer available, but the 8-speed shifters actually work quite well with 7-speed cassettes, especially with modern rear derailers.