Last night, when Jan and I went to our tai chi class, we noticed that her bike had developed a click, once per pedal revolution. When we got home I tried a few experiments and discovered that I could feel the click if I gripped either crank and rocked the bike back and forth whilst applying gentle forward pressure on the crank. This should not happen to a bike that is not yet 6 months old.
I telephoned Thorn Cycles to ask advice and spoke to Steve, one of their mechanics. He wanted to be 100% sure that it was the bottom bracket and not a pedal, so he asked me to take the pedals off, grease the threads and replace them and also check that all five crank-arm bolts were done up tightly. They were, and the click was still there.
In the event I took the cranks off, for which I had to find my crank-pulling tool which I have not used for at least 25 years, and I discovered that I had a tool for tightening bottom brackets, which was in a kit I bought a few years ago and had never used. I managed to tighten the BB, reassembled the bike, and the click seems to have gone.
Later, I succeeded in removing the sprocket form the tandem’s Rohloff hub, something which has never been done before in over 11000 miles of cycling. This made me especially pleased, since I damaged the Rohloff of my solo machine when I attempted the same job a few weeks ago, and I had to send it back to Thorn to get it repaired.
Next I took the chain rings off and cleaned them – another job which I should have done before. They really need replacing so I’ve ordered some new ones. I also went to Richardsons’ and bought a new chain.