Tuesday, January 05, 2016


Getting to know this bike has been quite the learning experience. I really didn't want to become anything close to an expert in cycling components, but alas, the journey continues...

After replacing both derailleurs, shifters, cassette, all the cabling, two spokes, freehub, tires, saddle, headset, and stem, everything seemed just about perfect. The bike is light and agile and FAST.

But she's still a smidge noisy in the bottom bracket area, and some poking tonight may have revealed...yet another hack to this already-hacked up bike.

The whole drivetrain that I replaced back in October turns out to have been older than the bike itself. No bigs, as the guy who owned it worked at a LBS and likely just grabbed compatible parts out of a bin to keep it running. But that's not even close to possible with what was done at the cranks.

Blue made the Axino to support a BB30 bottom bracket, which is not compatible with Shimano's Hollowtech II components. This bike, though, is running a very Hollowtech II Dura Ace 7900 crankset. Given that many "conversions" are just cheap adapters, that's likely the reason why it rubs on the front derailleur ramps when I'm at either end of the rear cassette.

And a quick check of the Interwebs tells me this is what is likely installed. A cheap Delrin reducer ring that's probably been mashed into place for years, taking hundreds of watts of force for hours at a time. Plenty of wear & tear on that guy, I'm guessing.

How did I stumble upon this today? What other way: by throwing money at the bike. I finally took the plunge and ordered a Stages power meter and was looking at what the installation would entail. And that revealed another damned hack to this drivetrain that I'd previously missed: the inner chainring is a Shimano 105 from the 5600 era.

So I'm super stoked to have a power meter on the way, but now I'm almost wishing I'd just ordered one for an Ultegra 6800 setup and replaced the whole damned thing. It would have been almost identical weight with a known timeline for the components. As it is, I'll probably have to see if Carytown Bikes can replace the hacked BB30 conversion with something respectable and STILL hate knowing I have such mixed components up front.

So after this is done, the only moving parts on that I won't personally have replaced (yet) will be the rims and brakes, neither of which are OEM components for this bike.

The good news is that if I decide the mixed pedigree of the crankset is just too much to handle, the Stages power meter will mate to any Hollowtech II setup, so I can just throw an Ultegra crankset on this bike and call it a day. It'll look funny, but given that the Dura Ace left arm is ~20g lighter than the Ultegra, and the power meter adds ~20g, it should be a weight wash (though the 6800 crankset comes in just a tick heavier overall at 765g vs 735g). And if I'm gonna go to that trouble, I might as well swap the Oval 520 cranks on the winter bike with some Shimano goodness so I can get power data from that guy, too.

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