Recovering by setting up my bike

After the marathon, I’m taking some time to get my bike set up for this season. Having another little project keeps me from going crazy with my training and allows some time for recovery.

Re-installing my Ergomo bottom bracket

I’m using an Ergomo as a power meter on my bike and have been quite happy with it. Sometime late year however, something strange must have happened, as the readings were about 20 watts low. (The first time I realized this was in my main prep race last year .. suffice it to say that it was not a good race as it took me some time chasing my goal wattage before I realized something was wrong.)

There was nothing obviously wrong with it, so I decided to re-install the bottom bracket that houses the measuring unit. I’ve done the installation a couple of times by now, so it was (almost) routine …

my bike on the work stand

the bottom-bracket area .. the Ergomo cables are still protected by black tape

a better look at the bottom bracket and the cables with the tape removed

First, disassembly:

• get the pedals off (remember that the left pedal is reverse-threaded, so it come off clock-wise)
• get the cranks off (there is a special crank remover tool for this)

crank remover tool

bottom bracket with crank removed

• now unscrew the bottom bracket (this requires quite some force .. this time the right-hand side is reverse threaded!) – requires a special Ergomo tool to properly grip the nut

view from the right hand side

• It was here that I realized that this nut has been loosened a bit, it was quite easy to get off. I hope that this was causing the funky readings.
• the left-hand side is regular threaded and is a little bit easier to get off .. just be careful with the cables
• then you can completely remove the bottom bracket

Then, re-assemble:

• clean & grease everything,
• then put everything back together using the suggested torques (quite easy to get these wrong, so use a torque wrench!)
• when mounting the bottom bracket, the Ergomo cables need to be in a certain position (after tightening!),

this is before tightening with the right torque. Afterwards, the cables come out in line with the down tube.

Piece of cake! After some more cleaning, fixing cables, lubing everything and pumping up the tires, I should be ready for my first ride of the season!