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  • Rotor - REX 1.1 Cranks - Black
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  • Rotor - REX 1.1 Cranks - Black

Rotor REX 1.1 Cranks


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    • Black, 172mm

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    Get cranking.

    Rotor has devoted itself to a new line of mountain bike cranks it's calling "REX," and they are based on the same successful Trinity Drilling System as all Rotor cranks. The REX 1.1 is for a 1x drivetrain.

    The Trinity Drilling System (TDS) is a method of hollowing out the cranks, which reduces weight and maximizes stiffness. Unlike traditional hollow crankset design, the Trinity Drilling System drills three channels from the pedal to the spindle. While these holes remove excess material, they also leave behind two thin walls, making them stiffer than the design of a single hollow chamber. The TDS creates a maximum strength-to-weight ratio, and the arms were constructed using a new 7055 alloy, which is both lighter and more durable than the more often used 7075.

    UBB30 & UBB24 axles ensure maximum frame compatibility. Without the bottom bracket they weigh in at 489grams. The Q-factor is 163.

    The Rotor REX 1.1 Cranks are available in sizes 170mm, 172mm, and 175mm. Please note the REX 1.1 does not include a chainring.

    • Item #RTR000G

    Tech Specs

    Arm Material
    7055 Alloy
    Arm Length
    170 mm, 172 mm, 175 mm
    Bolt Circle Diameter
    BB Type
    BSA , BB89 , BB92 , PF30 , BBRight
    30mm, 24mm
    Q Factor
    Compatible Components
    Rotor QX1/No-QX1
    Claimed Weight
    489 g
    Recommended Use
    mountain biking
    Manufacturer Warranty
    1 year

    Tech Specs

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    • Q & A

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    Unanswered Question

    I have a Rotor inPower left side only power meter. I was using it on my road bike with 3d+ drive side crank arm. Could I use it to attach to the drive side of this mountain crank if I wanted to use it on a 1x mountain build?

    Unanswered Question

    I have a pf 92 gxp bb how can I choose a 24mm spindle when ordering a rx1 crank.?

    there is no option to choose between a 24mm spindle or a 30mm spindle.

    how do I know for sure that the rx1.1 crank that i'm ordering comes with a 24mm spindle and not with a 30mm spindle?

    this crank is compatible with BSA (68 & 73), BB86, BBB89, BB92, BB30, and BBRight bikes. if you want to email me at I can help you out on compatibility with your frameset.

    Unanswered Question

    What's the BCD? Spider looks *maybe* close...

    What's the BCD? Spider looks *maybe* close to XX1? What about ring availability or cross compatibility if it is a 76 BCD like XX1?