Stages supply the power meter pre-installed on a non-driveside crank arm, so to install the system you need to remove your existing crank.

Some cranks come with the axle attached to the non-driveside arm (SRAM Red and Force, for example), whereas other have it attached to the spider itself (Shimano Ultegra, FSA SL-K Light), but because Stages power meters come as non-driveside crank arms, they only work with cranksets where the spider has the axle attached. That’s why you can get a Stages power meter for a SRAM Rival crankset, but not an upscale SRAM Force or Red crankset.

Similarly, Stages currently only make their units for alloy cranksets as they say that carbon doesn’t provide a consistent enough deflection curve, so if you run a Campagnolo groupset you won’t be able to get a matching unit and might have to change to a different brand. All in all, Stages currently offer their power meter as an option with 12 cranks, from £599 to £799.

Our bike has a Shimano Ultegra chainset and removing the non-driveside Ultegra crank arm couldn’t be easier. First, you need to flick up the stopper plate that joins the two bolts together – forget that you’ll find removing the crank almost impossible.

Then simply use a 5mm allen key to loosen both bolts (an anti-clockwise motion). The bolts should be torqued pretty tight, so make sure that your allen key has enough length otherwise you’ll have to muster up an awful lot of force to shift them.

Next, use Shimano’s Hollowtech 2 crank tool to remove the star-shaped fixing bolt. This one shouldn’t be too tight at all, but remember to loosen the allen bolts first otherwise you won’t be able to shift it.

When the bolts are loose and the fixing bolt removed, you can slide the crank arm off. It may take a bit of (gentle) coercing, but should come off without needing too much force.