So, I had a creaky crank on the Superbe. (I still have a creaky crank but that’s another matter).

Diagnosis without taking the bike apart can sometimes be daunting. The one place I go to above all others is sheldonbrown.com you can pretty much look up anything and find what you need. Moreover since Sheldon’s sad demise in 2008, a cadre of friends and loved ones have been keeping this resource alive and updated. After looking up the common symptoms, and using my limited prior knowledge, I figured my problem was one of the components in the bottom bracket (hereafter BB).

So fun thing about old bikes, sometimes they use technology that is, well, dated to put it mildly. The Superb uses something called cottered cranks. By this they mean the peddle arms are held in place by a pin (cotter) which keeps the arm wedged tight to the crank. So two things had to be done: 1. remove the pedal arms, for which I used his article here and; 2. repair whatever fiasco i found in the BB.

Step one was accomplished easily enough with a hammer *grin*.

Step two was both exciting and a little scary. Having removed the crank arm and the face plate for the BB i then found the ball bearings rolling around loose!

This was not good. There’s a little metal cup that is supposed to hold the bearings in place, this cup was nowhere to be found. I mean it. I fished around in there for a good 30 minutes, moreover, there was 1 ball bearing missing. In my usual manner I followed this discovery with an expletive.

Fortunately I had removed the BB from a donor bike earlier in the week — see the Sorrento files for details. And as luck would have it the cup and bearings were the right fit for the BB on the Superbe. So I greased it up and got ready to install it. But then I discovered another problem … there is a little retaining ring inside the replacement cup holding the balls in place … where was the old ring? Looking at the debris I fished out of the Superbe I noted there were bits of degraded plastic in a roughly semi-circular shape. Could it be the ring was plastic? Surely not? Regardless, it looks like the plastic ring hand disintegrated at some point and hence the wonky seating of the bearings and the creaking crank.

I fit the BB back together, faceplate replaced, I got the crank arm and cotter pin back in but the bolt for the top of the pin would not re-engage with the threads on the cotter pin. Bugger. In driving the pin out i had bent the threads.

So this morning I took out the dremmel, cut-off the top three turns of the thread on the pin and presto, the fresh thread connected nicely and we have a repaired (and freshly greased) bottom bracket.

Test ride reveals that the creak is still there but it is much less pronounced. I’m wondering if the same problem persists on the drive side of the BB. I suspect another trip into the seamy underbelly of BB repair will be in order sometime in the next week.

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