So yesterday I did some maintenance on Crook, following the Day on the Ride event which marked my experiment with the 82-inchgear as a default gearing for ALC. Nope, it may work for flats and rollers, and it may have even worked on a 60-mile China Camp loop, but over a whole day, including longer climbs, it just took too much energy. Time to cog down! And so I did. I also made some adjustments to bar angle, and took a look at my alarmingly loose bottom bracket after that 90-mile day. One cup was loose, the axle could slip about 5-7mm side to side, and it was ugly. So, I pulled the cranks, checked the BB spindle for deformation, checked the threading of the cups, and reassembled tightly. So far so good… we’ll have to see if the cup comes loose again. My working theory: Lung and I both tried greasing the BB cup where it met the BB shell, to reduce aluminum frame squeak. I wonder if this meant less stable purchase for the cup under the extreme torquing of the spindle by the cranks in that big gear? One would think that a properly installed set of cups couldn’t move, since there’s theoretically no action on the cups themselves, other than the internal bearing pressure from the spindle cartridge… but maybe those giant mash turns apply such an eccentric load on the spindle that it pushes hard against the shells. I don’t know…

Anyway, Put everything back together, tested it, and took off for the day. This day included a Paradise Loop, which was delightful in the lower inchgear. However, on the way home I noticed an increase in BB creaking (I didn’t re-grease the cup) and I felt more shifting under my left foot, which I thought was more trouble with that pedal and cleat, as they’ve been harder to get out of lately.

This morning, took off, felt MORE grinding sensation, or lifting, under my foot, and something didn’t feel right. I got through Tam junction and was heading over Almonte hump when I could definitely feel instability in the crank arm. I stopped and checked it and lo, to my surprise, the crank was coming loose. WHAT the.

Now, normally, I’d just whip out an allan, take care of it, and proceed. But funny thing about the 8mm key: it hardly appears in field multi-tools. I have one. It lives in the set of ride tools I took on Day on the Ride… now on a drying rack after being de-Poweraided. GRRREAT! So, I tamped it on, literally, as much as I could, hand tightened the crankbolt, and one-legged it to work. I got as far as WHole Paychecks, and the crank fell right off, creating the undoubtedly amusing sight of my left leg flying forward and out as I tried to keep the clipped-on crank from falling back into my wheel.

Now, this never happens to me, but I was actually one half-block from ACE, so I noodled over there, and sure enough, at 8:29am, I was a minute before opening. So, obviously, I proceeded to clean them out of 8mm loose keys. Tightened the crank up properly, took off to work, BB shell no longer supersqueaking, everything golden. And now, I have 8mm keys for every ride kit as well as the garage. HA!

Anyway, weird feeling, second time it’s happened to me (the last being the broken crankon Toro in Napa Valley) and hopefully the last. I can only figure that I must not have gotten enough torque on my little multi-tool 8mm when I was reassembling the crankset the other morning, not screwing it in deep enough. Oh well, no loss, other than some crank arm paint!

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