Middleburn RO2 cranks come complete with an axle, plus axle nuts and fittings. RO2 road X-type cranks are for use in the external bottom bracket.
These Middleburn RO2-X-175 cranks (including SP-RO2-X-94-X2 spider weight) is approximately 568g including all fittings. The Q factor is approximately 153mm.
Middleburn cranks were first developed in 1991 and since then the cranks have undergone many refinements. This is the latest road bike crank which is designed to work with the external bottom brackets but also with push-fit type bottom brackets with the use of a different axle length. The design is the result of advanced 3D and stress modelling technique that ensures they are amongst the stiffest cranks on the market but also light too.
The cranks are hot forged from high quality 7075 T6 aluminium. They then go through a CNC machined process and are then hand polished followed by anodised before being re-machined with the Middleburn logo.
All cranks go through the same procedure so whichever crank arm you choose will be to the best quality.