overview

These special cranks from Rotor were designed with the racer in mind. The '3D' name comes from their robust looking crank arms which undoubtedly make any bike look more sporty and aggressive. Rotor wanted cranks that would be stiff enough for rider's looking for the ultimate in performance. The crank arms receive a special machining treatment - Trinity Drilling System - which drills out three long cavities in each arm. The result is a massive weight reduction without jeopardizing the stiffness. Furthermore, Rotor reduces the Q-Factor to an astounding 145mm!

specs

• Lengths: 170, 172.5, & 175mm
• BCD: 110
• Spindle: Steel or Titanium
• Q-Factor: 145mmNote: Bottom Bracket & Chainrings not included

accessories

Rotor Q-Ring Set Rotor BB1 bottom bracket

photos

reviews

Product Rating: (4.00)   # of Ratings: 1   (Only registered customers can rate) (Only registered customers can rate) 1 - Terrible 2 - Bad 3 - OK 4 - Good 5 - Great 0% 50% 100% Sort: New to Old RE-SORT COMMENTS: Helpful to Less Helpful Less Helpful to Helpful New to Old Old to New High to Low Rating Low to High Rating Showing comments 1-1 of 1 1. BikeRadar on 12/13/2011, said: Well known for their elliptical Q-Ring chainrings, Rotor also make a range of lightweight cranks to match. The 3D cranks have been designed with input from the Cervélo TestTeam, including sprinter Thor Hushovd, and feature triple-hollowed aluminium arms. To create the hollowed structure, Rotor have bored out three holes along the length of the crank, using CNC machining, before machining the external surfaces to further reduce weight, a method they call the ‘Trinity Drilling System’. A replaceable and heavily machined chainring spider (available in compact or standard chainring sizes) is attached to the driveside crank, and the 24mm axle is compatible with Shimano’s external bottom brackets as well as Rotor’s own SABB (self aligning) unit. Out on the road power transfer was very good, but we did find our chainrings – Ultegra and Rotor Q-Rings – flexed more than with other race inspired cranks when the chainline wasn’t perfectly straight. Our testing showed the chainring spider was to blame, and for the slightly delayed shifting that came with it. For riders whose usual routes involve frequent shifting between rings, the delayed response may begin to grate after a while, but in all other respects the 3Ds performed very well. Fitting was very easy, with the unique Dual Thread Technology (DTT) fixing bolt clamping the non-driveside crank to the axle by using two different pitched threads on a single bolt. It’s important to follow Rotor’s instructions as the DTT bolt works in a slightly different way from standard fixing bolts, but the upshot of this small change in procedure is that the clamp area is less heavily stressed by clamping and so can be more heavily machined for reduced weight. We tested the titanium-axled version which weighs 497g, placing it squarely in the lightweight class. The precisely etched graphics and black and red colour scheme look great too. For £150 less you can buy the steel axled version which adds just 34g to the total weight. Good power transfer and light weight are both positives but we’d like to see Rotor stiffen the chainring spider to make these real winners. Was this comment helpful? yes no   (0 people found this comment helpful, 0 did not) Showing comments 1-1 of 1