Shimano Revoshift Sl-rs35 3x6s 3x7s Grip Twist Shifter 18s 21s Mtb Bicycle Bike Shifting Lever - Bicycle Derailleur - AliExpress
My daughter's Trek came with a 6-speed Shimano Revoshift SIS Index. It's a new bike. She can shift to higher gears easily but does not have the grip strength to shift back
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