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Dia Compe/Dia Tech bar-end shift levers £39.99 pair
A very long time ago, about two decades in fact, there was only one way to shift gears without taking either hand off the ‘bars and it resided at the further end of the drops. ‘It’, of course, is the ‘bar-con’ or bar-end control and it still widely available thanks to its suitability for gear shifting when riding on tri bars.
It was, or they were, once popular with road sprinters for the ability the change gear while maintaining control at speed and with ‘cross riders for the control they offer over rough ground. Few road riders favour them now since dual-control levers offer even finer control along with the miracle of indexing. Most bar-cons of current manufacture are indexed; designed as they are for use with today’s competition transmissions, they need to offer time triallists and triathletes the same shifting precision as found with regular shifting.
These bar-cons from Dia Compe are not. Instead, they utilise an idea that, until indexing came along, represented the apogee of derailleur control. Now known as Power Ratchet, it was originally developed as Retro Friction by the Sun Tour company and was available for both bar-end and downtube operation. It is stunningly simple; there’s a fine-click ratchet mechanism that locks in friction mode when returning the lever with the pull of the derailleur spring and ‘freewheels’ when pulling against the derailleur spring. For younger readers, the alternative was friction in both directions…
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The result is an exceptionally easy operation in both directions, since the spring helps move the lever against friction while the spring alone offers resistance to movement against its pull.
Why fit them? The transmission fitted to the author’s latest acquisition was based on Sachs New Success dual control levers with Quartz derailleurs working over a Maillard seven-speed ‘block’. No way did the indexing work properly and there was no obvious system that would work apart from some sort of friction shift.
My first thought was to search for a pair of Sun Tour Retro Friction levers, with bar cons preferred because tricycling is easier with both hands on the bars. However, a few moments searching the web found a much better bet in the shape of brand new components of the same standard. On they went, transforming the ‘barrow’s gears from a miserable mish-mash of missed shifts to slick, easy and reliable operation.
Perhap the most apt comparison is with the Shimano nine-speed bar cons previously fitted in an attempt to achieve the same result. In addition to indexing, they have a friction setting. While it works, it is not a patch on the feel of Power Ratchet.
Lacking indexing, the Dia Compe bar cons work with any and all derailleur transmissions. They fit any dropped handlebars and work best with the shift cables concealed under the bar tape all the way to the centre bulge, although the old-school style was to run them from the under the tape just below the brake hoods. Either way, job done.
