The XM557 X1 is the first complete B.O.R 1-speed crankset. It combines all the technical innovations of the XM557 Basic cranks with all the advantages of an easy-to-use single-chainset and the ultimative compatibility of bottom brackets. And thanks to the "Smart Spindle System" allows the crank platform now installed in 11 different bottom bracket types!
The XM557 1X is the synthesis of the XM557 Basic cranks as a “carrier” (460 g) and a mounted XX1 drive-train unit (from 60 g) and results at just 520 grams. With its 76 mm hole diameter (like SRAM XX1) it provides easily replaceable 30T - 32T - 36T - 34T - 38T chainrings.
Smart Spindle System
- Fully CNC machined (Light Alloy 7022/7010/7051), anodized with noble laser-Logo
- Crank arm lenght: 175mm - 165mm, 170mm and 172.5mm at request
- For 1x10-speed or 1x11-speed drive
- chainline: 49mm
- Q-Factor: 164mm
- U-Factor: 147mm
- K-Factor: 96mm
Developed in cooperation with Tune 2012, the “Smart Spindle System” serves as the basis for all B.O.R MTB cranks and secures for installing our cranks into 11 different bottom bracket types.
Overview of all compatible bottom bracket types:
BSA68 / BSA73 / BSA73 MTB eType / ITA70 / BB30/73 MTB Cannondale / BB85/84,5 MTB Specialized / PF30/73 MTB / BB386EVO/91,5 MTB PRESSFIT / BB Right/84 MTB PRESSFIT / BB92/89,5 sym. MTB Pressfit / BB92/92 asym. MTB Pressfit
The specific bottom bracket is available separately.
Smart Drive-Train Concept
B.O.R. provide a versatile usability of the crank. Even regular with a spider or "Plug and Play"- power measurement on the spider. Thus B.O.R cranks are “Power Meter-ready” and enable the simplified retrofitting of measuring units from SRM and Power2Max!
Spindle length, chain line, K-factor and Q-factor of this crank was designed for regular CrossCountry-, Marathon and AllMountain Frames! These usually have a rear dropout clearance of 135-148 mm.
The XM557 cranks are optimized for CrossCountry-, Marathon and AllMountain use. NOT
recommended for Downhill or Enduro use!
Standard arm length 175mm - for 165mm, 170mm or 172.5mm please contact our service team.
A Shimano cassette tool (such as the Park Tool FR-5 Freewheel Remover) is required to mount the lock nut. The crank is supplied without a manual.