bike components ⁽²¹⁾

I now have three sets of Rotor aluminum Aldhu cranks, or four counting the carbon version on my Ritte. My Marauder uses an older pair of Rex 1.2, and my Stooge sports a current set of aluminum Kapic cranks. Out of seven bikes, six are equipped with Rotor cranks. I love the modularity of Rotor’s cranks with the availability of various axle lengths, different spiders, and a wide selection of round or oval direct mount rings. I wish they would only offer Kapic axles for fat bikes.

Whenever you switch a part on your bike, it’s important to do your homework. A coworker of mine once wanted to change the stem on his bike. He got one, went on the put it on the bike, only to realize that his handlebar wouldn’t fit. He had purchased a stem with a 31.8mm clamp. Unfortunately, his bike was equipped with a 35mm handlebar. It’d be easy to laugh and say what a noob. But we can’t all be experts in everything. I’m certainly not. After several winters of riding my fat bike, the axle of my crankset has worn where the bearings are seated. Without tightening the pre-load adjuster, there was noticeable play. A tightened pre-load adjuster doesn’t remove that play; it only hides it while the bike is in the work stand. The play is still there under every pedal stroke and will only worsen over time. It will also lead to premature bottom bracket failure. It was therefore time to replace the axle. Because I chose a SRAM XX1 carbon crankset at the time, a simple axle change isn’t possible. The axle and the non-drive side crank arm form an inseparable unit.

In my previous post, I introduced my BB3106 bottom bracket. The cycling world is full of different bottom bracket standards, and each time a new one is introduced, every cycling forum and every comment section of every cycling news website moans about it. So, I'm gifting the cycling world with yet another "standard." But no need to worry. Specifically designed for Rotor Kapic cranks with Boost axle mounted to a Stooge MK5, BB3106 isn't anything the bicycle industry is going to adopt. And should it ever become a thing, remember that you saw it here first!

If there's one thing I would change about the Stooge MK5, it's the eccentric bottom bracket. With a 1x12 drivetrain, I simply don't need it. I acknowledge that there are benefits to having one. For one, the MK5 can be set up single-speed or geared. As such, it has a wider appeal, and should I ever part with it, the circle of potential buyers would be considerably larger. My experiences with the two EBB-equipped bikes I've owned, however, were more bad than good. My Niner One9, for instance, had a setscrew EBB. The setscrews quickly ate themselves into the EBB, and the BB shell ovalized over time, leaving a wide gap between the shell and the EBB. The gap filled with dirt, and the whole setup was creaking more often than not. My Air9 Carbon came with Niner's own Bio-Centric bottom bracket, a design that clamps to the outside faces of the EBB shell. In theory, this seemed great. Machine a precise cylindrical BB shell with parallel outside faces and clamp two eccentric cups against those faces. In practice, it was pretty shitty, to say the least. For one, machining tolerances were such that a Bio-Centric cup would more easily turn on one side of the shell than on the other. But much worse was that Niner designed large cutouts into the shell so that shifter cables could be routed internally. This dramatically weakened the shell to the point that the proper tightening torque of the Bio-Centric was enough to crush it. It was an extremely troublesome design that creaked a lot as well.

This is a continuation of Part I from July 18th and Part II from July 24th, in case you missed them. When Andy launched the MK5 in the spring, ETA for the framesets was August. Because a certain percentage of the population has forgotten that living in a modern, democratic society doesn't just come with personal liberties but with responsibilities as well, we live in a seemingly never-ending pandemic. And as long as the Coronavirus has the upper hand, our economies will continue to stutter each time case numbers explode, supply chains will remain broken, and bike components will be in short supply.