Over the years we have made a lot of stuff for the top guys to personalize their bikes. Chad Reed is one of the guys that knows what works for him and has his bikes setup that way. One of his requirements is having a reverse rotating cable adjuster when running a cable clutch. He has ridden for blue, red, yellow and green teams over his career and we have been there making the “left hand adjuster” parts for him. As a side note, it looks like he could have benefited from one of our new transponder mounts.
Here is an off the rack RC-8 perch. The perch assembly is the platform to make a heap of rider preference refinements. We can make special shaped levers with any pivot location. There are different materials available to produce the special shapes from. The refinement offered here is an adjuster that rotates in the opposite direction from standard.
This view makes it easier to get what the “standard rotation” is. Since the beginning of higher spec levers, (Magura late 60’s?), the adjusters have been right hand thread as shown by the green arrows. This rotation matches common machine tools used in producing the parts. A left hand thread, reverse rotation, requires special taps and short production runs of mating parts which adds to cost.
The reason for the reverse rotation is “direction of mass” related. When doing the on-the-fly clutch cable adjustment your hand rolls the top of the adjuster wheel forward as in the green arrows above. The motion of your upper body is forward and away from the center of gravity. With the reverse rotation adjuster the top of the wheel is rolled oppositely as shown with the red arrows. This keeps your upper body closer to the center of gravity.
What is a left hand thread? Shown here is the angle of the thread
comparing a left and right hand thread. They are dimensionally identical while having opposite rotations to tighten/loosen.
Since the parts are identical in size and color we emboss the “L & H” right on the parts so there is no confusion.
To the untrained eye this looks like the standard adjuster. It installs in about two minutes and may refine your bike to suit you better.