Jackyll the Tandem Part 5: Suntour Shifter Rebuild



In the days before integrated brake/shift levers were the norm, there was little alternative to the traditional downtube shift levers.  If you wanted to keep your hands on the bars whilst shifting the only option was bar-end levers.  Having started riding road bikes with downtube shifters, I fully appreciate the usefulness of having both hands on the bars, particularly when shifting around corners or on descents.


Bar-end levers essentially feature the same mechanism as downtube levers except they are mounted inside the ends of handlebars.  The mechanism in these shifters features a miniature ratchet which evens out the lever movement from shifting down (against the derailleur spring) to shifting up (with the derailleur spring).  This is called a retrofriction shifter, made famous by Simplex.

This results in a distinctive ratcheting sound when you shift to a lower gear.  Suntour adapted this mechanism into their own classic bar-end levers.  I decided to purchase a pair for Jackyll as piloting a tandem is difficult enough without having to worry about shifting downtube levers.

The mechanism itself is quite simple, and a rebuild really just involved disassembly and cleaning with a light relubrication.  The mechanism as you can see has a ratchet and pawl sandwiched with some washers.  The screw that clamps these washers determines the force required to turn the shift lever.  This adjustment is crucial in tuning the feel for friction shifting which is what these levers are known for.



The ratchets were lubricated and the pods sanded back from a thin silver anodising to bare alloy and then polished.  The shifting action is now perfectly smooth and requires very little effort to move it to a position.



I've used plenty of bar end shifters before, however the light feel of these and the ratcheting action make these some of the best for friction shifting.  Now they are back together again and ready to go on the bike.  Thanks for reading!

1 comments:

  1. Triple STI shifters are hard to come by in the Philippines. Bike shops here sell mostly double shifters. So I fitted a SunTour barend on my bike to shift my triple crank and swear it shifts better than one on an integrated STI.

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