Replacement self-extracting bolt assembly for the 24mm ISIS-spindle Helix Race e*spec Alloy crank — the fitment e*thirteen builds for Bosch SX/Gen4, Brose S Mag and TQ HPR50 e-bike motors.

Compatibility & fit

Fits the ISIS-spindle Helix Race e*spec Alloy crank built for Bosch SX/Gen4, Brose S Mag and TQ HPR50 e-bike motors (the 21.5mm and 26mm offset versions). Not for the 30mm-spindle Helix Race Alloy/Carbon MTB crank — that uses the separate CSS40-108 kit.

e*thirteen's Infinite Ride Warranty covers this part for 10 years against manufacturing and material defects; it doesn't cover wear from normal use, and crash or impact damage is handled under the standard crash-replacement option rather than a free replacement. This is in addition to your rights under the Australian Consumer Law, so keep your proof of purchase. For warranty support, return the product to Tune Cycles and we'll manage the claim with e*thirteen's Australian distributor.
  • Self-extracting bolt — pulls the crank arm without a separate crank puller
  • Fits the ISIS-spindle Helix Race e*spec Alloy crank (Bosch SX/Gen4, Brose S Mag, TQ HPR50)
  • Direct OEM-spec replacement assembly
FitsHelix Race e*spec Alloy crank, 24mm ISIS spindle (Bosch SX/Gen4, Brose S Mag, TQ HPR50)
TypeSelf-extracting crank bolt assembly
Brand part numberCSS40-107
SKU DTW-ETT-CSS40-107
Barcode # 4711280343386
Brand e*Thirteen
Shipping Weight 0.2000kg