clengman

I just purchased a set of shifters from an ebay seller. The ad was for SL-BS64 8-speed shifters. Got the shifters today. The model number clearly says SL-BS50 which I see are 6/7 speed shifters. When I move the rear shifter through the full range of motion I feel 8 positions including the hard stops at the top and bottom of the range. In other words, if I move it all the way to the bottom, it takes 7 clicks to move all the way to the top. This is how I would expect an 8-speed shifter to work. Is that correct? Is it possible that the seller took the indexing mechanism out of an SL-BS64 and put it into an SL-BS50 shifter? What's going on? I'm in the middle of accumulating parts for an overhaul of my drivetrain and I don't have everything I would need yet to make sure it works. The seller accepts returns, but my return window will have expired by the time I get around to finishing this project. I'm inclined to just not mess around and return them while I can, but if someone can convince me that what I got will work, I'll probably keep them. Any suggestions?

bikemig 

I'd return them.

canklecat

I have the SL-BS64 8-speed shifters on my hybrid, although with a 7-speed rear derailleur which limits the shift range. Definitely 8-speed index/friction shifters. I recall that some Shimano SIS modules can interchange, but I don't recall details. It's all on Shimano's website, although it'll take some digging through the archives of scans of illustrated manuals, brochures and diagram sheets.

If I'm recalling correctly, SIS index shifters usually have one more clickstop detent besides the designated speed range. But that doesn't guarantee a 7-speed shifter with eight clickstops will cover an 8-speed cassette in index mode.

Here's the problem I encounter using that bar-end shifter with 7-speed RDs -- and I have both Shimano Exage 500 CX and Deore LX long cage RDs, which are nearly identical.

I put an 8-speed cassette on the wheel just to check the coverage. No problems with covering all 8 cogs in friction mode, despite the 7-speed RDs.

However in index mode, while the shifter will click into the eighth detent and shift onto the largest of the eight cogs, under pressure such as climbing a hill, the RD will slip back to the 7th cog (in my case, from the 32T to 28T cog). The problem is a nub or projection molded into the RD's metal body that limits cage swing/pivot. The RD will shift, but barely. So any pressure causes it to shift to the next largest cog.

However in friction mode it will hold the 8th cog, no problem.

You might try this with the bar-end shifter you received and see if it works satisfactorily. If the shifters were cheap enough it might be worth keeping. Otherwise, return 'em and look for the SL-BS64 8-speed shifters.

clengman

Thanks. That's good information. I contacted the seller and he was able to find a set of SL-BS64 in his inventory. He's going to exchange them for me. So hopefully all will end well.

canklecat

Sounds like a good resolution. You'll like 'em. I put a set on my hybrid with Nitto Albatross upright swept bars. I can shift using my little finger to pull up, and palm to push down, while keeping my hands on the grips and fingers on the brake levers.

Several friends use these and other bar-end shifters on their drop bar bikes but I haven't tried that yet. I do have one road bike project that I may set up with Shimano 10-speed bar-end shifters, although I might save those for an aero bar setup to see if I can get accustomed to the aero position on a TT/tri-bike.

icemilkcoffee 

Just for posterity's sake, I checked the BS50 7 speed barcons in my 'stash, and just like the OP reported, it goes through 7 clicks- ie. it has 8 positions. Don't know why Shimano did that, but there you have it.

Cynikal 

I have used 7 speed thumb shifters on 8 speed cassettes multiple times. The space after the last index gets stopped by the limit screws. Works just fine.