KCNC’S K-type RD2 cranks are real eye-catchers, with extensively machined arms, further lightened by twin cavities running along their length.
The search for light weight also extends to the scandium alloy axle whose neatly splined ends are held in place by extra-long crank bolts for extra durability.
Stainless steel bearings spin freely in aluminium BB-cups and feel wonderfully smooth at first, though ours developed play after 100km that the adjustment system couldn’t remove. All this shaving and saving of weight has left the RD2 a little flexible compared to Shimano’s top-end crank sets, but for fast-paced TT-riding, flexibility was never a cause for concern.
Shifting from the KCNC chainrings was good, but there was a rhythm-breaking delay as the chain scrabbled for purchase during rushed shifts.
At 660g (with 68mm threaded BB) these are a good way to slice weight off your drivetrain, if that’s a priority.