Bikerumor Monday Mystery Pic: Mystery Shifter

bikerumor mystery shifter

Photo submitted by Brian Kavanaugh, “Attached is a pic of the left-side front thumbshifter on my well-thrashed and still much-loved 1985 Schwinn Sierra. What model shifter is this? Its original right-side companion was destroyed in a trail mishap involving a tree back in ’86 and was replaced at the time with a new-fangled SIS-style thumb shifter. I’d like to find a replacement to restore the cockpit’s original symmetry, plus I love the ratchet-style shifting action. I haven’t been able to find any images or info about this shifter. Other than the words “Shimano” and “Unishift Control” on the top ring, there are no markings anywhere on the housing.”

Readers, any help with this? More pictures after the break.

Attached is a pic of the left-side front thumbshifter on my well-thrashed and still much-loved 1985 Schwinn Sierra. What model shifter is this?

bikerumor mystery shifter

bikerumor mystery pic

Comments

michael gleason - 09/10/12 - 7:59am

Suntour thumb shifters.

Jon MacKinnon - 09/10/12 - 8:24am

Looks like it could be something along the lines of a SL-M700, that’s what a google search for “shimano unishift control” came up with. It also brought up this auction…

http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&item=110808800241

Jon MacKinnon - 09/10/12 - 8:26am

Apologies, after looking through this page

http://mombat.org/Schwinn_Specs.htm

I found that it is most likely an SL-AT50

http://www.ebay.com/itm/Vintage-Shimano-left-thumb-shifter-Unishift-Control-SL-AT50-/330754409159

Steve - 09/10/12 - 1:31pm

Beautiful bike! Love the smokey chrome finish. Can’t get anything like it due to it being horrible for the environment.

brian - 09/10/12 - 9:09pm

Thanks for the ace detective work Jon, now I’ll know what to be on the lookout for. The M700′s are fairly common, but I’ve never found the SL AT-50′s…..yet.
@Steve – yeah the “black chrome” was pretty hip back when. A lot of chrome platers offer it so it can’t be too bad.

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