These cranks are beautifully made and are both precise and well ﬁnished, but we were expecting a bit more in terms of arm stiffness. We measured 1.143mm of deflection on our testing jig, compared to 0.940mm for Shimano's benchmark XT cranks.
Having said that, the RS8s felt okay underfoot and are certainly stiff enough for the job. Shifting isn’t in the same league as it is for cranks from the big brands, but we do like the slippery, super-durable Hardcote ﬁnish on Middleburn's Slickshift chainrings. This gives a very positive feel once the chain has engaged with the ring.
A bottom bracket isn’t included, which reduces overall value – we’d recommend a Hope unit for £70. We’d also like to see some proper compact double options to add to Middleburn’s already deep vault of options.
However, the ﬁnish on the crank arms is incredibly long lasting and robust, and the crank itself is lighter than Shimano's SLX unit. The RS8 also has a lifetime warranty against manufacturing defects.
* Please note: The price quoted above does not include the chainrings.