I have been riding the Colnago a bit and it is a very nice bike, extemely stable and light. The only problem is that the crankset is a standard road set, 53 and 39 tooth rings, which is a bit big for a more mature rider, like myself, with bad knees. So I have been contemplating a change to a ‘compact crankset’ with 50 and 34 tooth rings to give me some lower gears for climbing. Since the drivetrain is fully Campagnolo, to keep it pure I have been looking at Campy compact cranks. Specifically I would like a 2006 Centaur silver crankset. Silver, because cranksets should be silver; I cannot see why there has been this recent trend towards black cranks and rings. The year designation is because of ridiculous, in my opinions, features of the 2005 and 2007 cranksets.
In 2005 Campagnolo launched their modern ‘compact cranks’. Everyone else in the world making ‘compact cranks’ at the time was just using the old standard 110mm Bolt Circle Diameter (BCD) standard. Campy used the 110mm BCD pattern, too, but for only 4 of the 5 bolts. They used a slightly larger BCD for the 5th bolt, saying that the non-standard alignment of that bolt was necessary to ensure proper alignment of the rings. Of course no one believed that, preferring to believe that the move was to ensure that users could not use third part rings on their Campy cranksets.
In 2007 Campagnolo changed their cranksets to use what they call ‘Ultra-Torque’, an two part spindle integrated into the crank arms and spinning on outboard bearings held in cups threaded into the standard bottom bracket threads. Shimano introduced a similar system a couple of years ago, but Campy held firm at that time staying with the tried and true square taper spindles. Shimano had moved away from the square taper a number of years ago, moving to a splined bottom bracket. I see no real reasons to move away from the square taper; the only real problems have been with folks who have not torqued the cranks onto the tapers tightly enough and thus have ruined perfectly good cranks. The splined BB spindles, both the Shimano Octalink versions 1 and 2 and the ISIS, have not really resolved the issues of poor mechanics. Enough folks have misaligned the splines and ruined either the BB, the cranks, or both to show that the splines were not a good fix for that problem. The only other reason cited for splined BB’s was that it allowed a larger, more robust spindle without adding weight though no one showed that the old square taper spindles were not sufficiently robust.
It looks like I am doomed to adopt the outboard bearings of the ‘Ultra-Torque’ system if I want a Campy ‘compact crankset’. Campagnolo cites the following reasons for moving to this system: lightness, rigidity, ergonomics, and maintenance, which I will touch on in reverse order. The maintenance advantage is that standard hexagonal ‘Allen’ key wrenches are used to tighten the bolts of the system. While ‘Allen’ keys may be standard, the large 10mm key used to tighten the bolt has limited use on bikes, and most square taper system use 8mm ‘Allen’ keys. You still need proprietary BB tools for both systems. The only extra tool needed in the square taper world is a crank extractor; big deal. The argument for ergonomics is even more ridiculous. The marketing hype states that riders no longer have to shift cleats for ankle clearance, presumably because the spindle end of the cranks are further outboard. But pedal/cleat placement is a factor related to the other end of the cranks, and since ‘Q factor’, the distance between the ends of the two cranks has not changed, the placement of pedals and cleats is unaffected by having the spindle end further out. Rigidity has not been shown to be a problem in the older designs, so what is the advantage? And finally to the argument for ‘lightness’. A 2006 Centaur ‘Compact Crankset’ weighs 646g; add 233g for the Centaur BB with 111mm spindle and the system weight is 879g. The 2007 Centaur ‘Compact Crankset with Ultra-Torque’ weighs 828g; add 49g for the outboard cups and bearings and the system weight comes in at 877g, a whole 2g or 0.2% savings. Whoopy! So I am left to ponder: why is the world moving to the outboard bearing systems?





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