SRM DuraAce 9000 and 9050 Compact: Interchangeable Crank Arm Length
I had an interesting conversation with SRM today, the SRM power meters having been reliable solutions for me over years on Moots Vamoots RSL and Moots Psychlo X RSL and other bikes prior (one bad Reed switch quickly fixed last year, nothing’s perfect).
I learned several things which might not be news to all, but bear repeating:
- The latest DuraAce 9000 / DuraAce 9050 compacts can take interchangeable crank arm lengths without any recalibration of the SRM needed, though these are a special crank arm made for SRM by Shimano (Shimano FC-SR70).
The rings can also be swapped out for another size. - The DA 9000/9050 battery life is up to a whopping 3000 hours, which is good for many years of life (2 hours a day or riding = 1500 days = 4 years), which is a very long lifetime).
- A new PC8 head unit is due out in late summer which will support ANT and GPS and Stages power cranks, the latter being exciting to me so I can run power on my mountain bikes, which I’ve long wanted.
Nothing shifts like DuraAce and so maybe I will bite the bullet and get one set up with 172.5mm crank arms, but also with a set of 170mm crank arms because I want to try the 170mm size once my body (legs) settle down.
My Cannondale Hollowgram SI/SL crankset might be upgradeable, and I’m likely to sell that too, though the ~250 gram weight savings is really appealing for the Everest Challenge.
See also Pioneer Electronics power meter.