Riders with a 2x9-speed mountain bike drivetrain (two chainrings, nine-speed cassette) who want to replace a worn or damaged pair of shifters like for like.
This is the Shimano Alivio SL-M3100 shift lever set for 2x9-speed mountain bike drivetrains. The left lever, SL-M3100-2L, is a RAPIDFIRE PLUS MONO that shifts the front double up and down with one lever, and the right lever, SL-M3100-R, looks after the nine rear gears.
The rear lever is RAPIDFIRE PLUS, so it can move up to three gears in one stroke, and its optical gear display shows your gear at a glance. Both levers mount with their own clamp band (clamp band type only) and have a shift cable adjuster, and Shimano lists the rear lever for MTB 9-speed rear derailleurs.
Front double, one lever
The RAPIDFIRE PLUS MONO left lever shifts the front derailleur up and down, with 2-WAY RELEASE so you can pull with the index finger or push with the thumb.
Three gears in one stroke
The right RAPIDFIRE PLUS lever can move up to three gears at a time, which suits quick shifting.
Optical gear display
The right lever shows the gear you are in at a glance.
Clamp band mount
Clamp band type only, with a shift cable adjuster on both levers.
Set
Levers
RAPIDFIRE PLUS
Shimano's trigger shifter for quick shifting. The right lever can move up to three gears in one stroke.
RAPIDFIRE PLUS MONO
A single lever that shifts both up and down, made for front double shifting with natural finger positioning while you keep a solid grip on the bar.
2-WAY RELEASE
On the left lever, relief shifts can be made by pulling with the index finger or pushing with the thumb.
OPTICAL GEAR DISPLAY
Shows which gear position is selected while you ride, including how many gears you can still select on the low side or the top side. The right lever has it; the 2-speed left lever does not.
Great for
Maybe not for
One size, clamped to the handlebar with a band. Match your rear derailleur (MTB 9-speed) and your front derailleur (2-speed) to the set.
Count your chainrings first
This 2x9 set has a 2-speed left lever, so it is for a bike with two chainrings up front. A bike with three chainrings needs the 3-speed left lever from the 3x9 set instead. Shimano recommends OT-SP41 outer casing for these levers, so it is worth replacing worn casing when you fit new shifters and cables.
