Power Meters / Powermeters (SRM, Powertap, Quarq, Ergomo, Vector, Stages, power2max, P2M, 4iii, InPower, Cinch)

just buy an old wired srm. Be ~£600 all in. Or less for si cannondale one as they're only good on bb30 compatible frames

ftfy :)

Wired SRM on SI SL cranks will be quite a bit more.

Wired SRM installation on my CAAD9 seemed to be straightforward and it's worked from day 1 - but then again it doesn't go out in the rain.