TRiPEAK AERO Asymmetric Oversized Pulley Wheel Kit for Shimano & SRAM Road 12-Speed – 12/18T
TRiPEAK AERO Asymmetric Oversized Pulley Wheel Kit for Shimano & SRAM Road 12-Speed – 12/18T
The TRiPEAK asymmetric oversized pulley wheel kit for Shimano & SRAM Road 12-Speed uses the listed 12/18T tooth combination. Check the exact rear derailleur model, generation and cage designation against the specification below. A shared Shimano, SRAM or Campagnolo name does not make different derailleur versions interchangeable.
Compatibility and supplied specification
AOPW AERO, 12/18T for Shimano RD-92xx/81xx/71xx 12s; SRAM AXS RD E1 RED/FORCE 2x12s
Specification: AOPW AERO, 12/18T Asymmetric Oversized Pulley Wheel Kits for Shimano RD-92xx/81xx/71xx 12s; SRAM AXS RD E1 RED/FORCE(2x12 speed), 2 sets of upper pulley side plates(4mm for SRAM/5mm for Shimano), 3 sets of lower pulley inner side plates; screws for SRAM lower pulley or Shimano upper & lower pulley
| Color | Part number |
|---|---|
| Black | EMA-JW1218A-A12SCBBK |
| Gold | EMA-JW1218A-A12SCBGD |
| Silver | EMA-JW1218A-A12SCBSV |
| Dark Blue | EMA-JW1218A-A12SCBDB |
| Light Blue | EMA-JW1218A-A12SCBLB |
| Green | EMA-JW1218A-A12SCBGR |
| Red | EMA-JW1218A-A12SCBRD |
| Orange | EMA-JW1218A-A12SCBOR |
| Purple | EMA-JW1218A-A12SCBPL |
| Pink | EMA-JW1218A-A12SCBPN |
Choosing this version
AOPW means asymmetric oversized pulley wheel. The larger pulley changes the chain’s path through the derailleur, so tooth count and model-specific mounting parts must match. AERO and EVO versions are separate product designs; choose by the supported derailleur and supplied parts rather than assuming all AOPW kits share the same fit.
Installation checks
TRiPEAK’s official AOPW upgrade article describes retaining the original derailleur cage without requiring a longer chain. It also asks installers to check that chain length is appropriate for the bike’s setup. Follow the matching TRiPEAK installation manual for the upper/lower pulley positions and mounting parts, then check shifting and clearance through every gear.
Will it fit a different generation of the same groupset?
Only the models listed in this product’s specification are supported by the information here. Road AXS, XPLR, Eagle and T-Type are distinct applications. Check the full derailleur code and cage length before choosing a kit or wheel set.
Why use an 18T lower pulley?
TRiPEAK’s 18T-versus-11T explanation describes a gentler chain-bending angle with the larger pulley. The asymmetric mount accommodates the larger wheel in the supported original derailleur arm. Read how the AOPW upgrade works for the design and fit details.
Compare TRiPEAK AOPW kits and pulley wheel sets, or send us your derailleur model to check fit before ordering.