To Santa

All I want for Christmas is more, more, more...

This is a line from a song from one of my heroes — Daffy Duck. He was talking about Christmas presents, but he could have been talking about gears on a modern racing bicycle. Think back to 1969, when Eddy Merckx won his first Tour de France. Everything I’ve read indicates that he won it with ten gears; ten in total. Double chain ring and a five speed freewheel. The bike almost certainly had a spacing of 120mm between the dropouts; even with a five speed freewheel, the wheel was probably close to symmetrical with regard to dish. Component manufacturers then continued on the inevitable climb towards more complexity and a greater number of sprockets on the rear wheel. Squeezing more sprockets onto a conventional rear hub led to problems with broken rear axles; the distance between dropouts grew from 120mm to 126mm and conventional hub/freewheel designs inevitably snapped axles; support on the drive side was pushed further under the hub with the more gears you loaded onto your freewheel, leaving an ever longer amount of axle free to flex and eventually break. This usually happened when you were at the furthest point from home!

Both Shimano and Maillard came up with designs that solved the problem, although the Helicomatic system from the French company is all but forgotten these days. They were similar in that both designs moved the supporting bearings in the hub drive side to the outermost location in the hub body, effectively eliminating broken axles. I regard the modern freehub design as one of Shimano’s greatest achievements; easily on a par with STI shifters. OK now, I’m a wheel guy and therefore biased, but there’s no disputing that the durability of the freehub design allowed for the possibility of incorporating ever more sprockets – and eventually, disc brakes – into rear hubs. Happy days were here, again…

Well, not quite.

While Shimano, Campagnolo and Suntour (remember them?) were busy stacking on gears, they didn’t always give much thought to the headache that their early hub designs caused me and my wheel building brothers; some truly egregious examples of wheel dishing had us shaking our heads. I remember building an early Campagnolo Chorus eight speed freehub; the drive side spokes were God-awful tight and the non-drive spokes could be flexed with my pinkie finger! After early examples of poor design, component manufacturers eventually came up with designs that successfully minimized the difference in tension between the drive and non-drive side spokes. They usually accomplished this by moving the non-drive side flange a little further to the center and finding a way to move the drive side flange a little further away from the center. Sometimes they employed a low flange on the non-drive side and a high flange on the drive side. Some manufacturers relied on using half the number of spokes on the non-drive side, helping to boost the tension on those spokes. We wheel builders could do the rest, by using lighter gauge spokes on the non-drive side, or going with a non-drive side radial lace.

The racing world is probably headed to disc brakes, 135mm spacing between the dropouts and sticking with 11 speed gearing. That means the average rider is headed in the same direction. I’m happy with the move to 135 mm spacing; the jump from 130mm to 135mm doesn’t sound like much, but it will go a long way to endowing rear wheels with superior rigidity and durability. I believe that we’ll have some of the strongest road wheels we’ve seen in twenty years…

Until they screw it up by going to 12 speeds!

Happy holidays!

-John