Ideal for riders maintaining a compatible Shimano 10-speed MTB or trekking bike who want the correct genuine pulley set instead of an aftermarket substitute.
The Shimano Pulley set (RD-M780) is the genuine replacement set for selected Shimano 10-speed DYNA-SYS rear derailleurs used on mountain bikes and trekking bikes. If your current jockey wheels are worn, noisy or showing extra play, swapping them out is one of the simplest ways to bring back cleaner drivetrain running and more consistent shifting feel.
This set includes one guide pulley and one tension pulley, so you can replace both wear items together rather than mixing old and new parts. The pulley design used here pairs a sealed-bearing tension pulley for low-friction running with a ceramic-bushed guide pulley aimed at long service life, which makes it a smart choice for bikes that still see regular trail, touring or commuter kilometres.
For buyers keeping an older XT or trekking 10-speed Shimano drivetrain going, this is the right sort of part: genuine fit, no guesswork on pulley sizing, and compatibility that matches the listed rear derailleurs. It’s a practical workshop fix when your derailleur still works well overall but the pulleys have reached the point where they’re affecting noise, chain control or shift accuracy.
Genuine Shimano replacement set
Made as a direct service part for the listed rear derailleurs, so fit and function stay true to the original setup.
Complete pulley pair
Includes both the guide pulley and tension pulley, making it easy to refresh the full derailleur cage at once.
Built for DYNA-SYS 10-speed
Designed around Shimano’s 10-speed MTB drivetrain platform for the correct match with compatible derailleurs.
Low-friction tension pulley
The sealed bearing in the tension pulley is intended to keep the drivetrain running smoothly with reduced drag.
Durable guide pulley design
The ceramic bushing in the guide pulley is aimed at long wear life in regular off-road and mixed-use riding.
Fits MTB and trekking applications
Suited to compatible derailleurs used across trail bikes, touring builds and flat-bar trekking bikes.
Good fix for worn shifting parts
Fresh pulleys can help tidy up drivetrain noise and restore a more precise feel when old jockey wheels are badly worn.
General
Compatibility
Features
DYNA-SYS
This pulley set suits Shimano’s 10-speed MTB drivetrain platform, built to keep shifting smoother across close gear steps and help the drivetrain stay efficient and durable on mixed terrain.
Great for
Maybe not for
Compatibility is the key buying check here: this set is listed for RD-M786, RD-M781, RD-M780, RD-M773 and RD-T8000, including RD-T8000-SGS. It is a 10-speed pulley set. The set includes one upper guide pulley and one lower tension pulley; fit the solid wheel at the top and the perforated wheel at the bottom.
vs Shimano Pulley set Y5RT98120 for RD-M8000/M8050
A genuine Shimano option for newer 11-speed DEORE XT rear derailleurs rather than older 10-speed DYNA-SYS mechs.
vs Shimano Pulley set Y5XH98120
Another genuine Shimano pulley set used across a wide range of lower-tier and mixed-model rear derailleurs, but not the same dedicated XT/T8000 option as this set.
vs Shimano Pulley set Y5XC98110 for RD-M986/M985/M981/M980/M820
A genuine Shimano pulley set for XTR and SAINT DYNA-SYS rear derailleurs, aimed at different high-end 10-speed mechs.
Check the derailleur model, not just the speed
A lot of Shimano rear derailleurs are 10-speed, but that doesn’t make every pulley set interchangeable. Match the derailleur model number first, then confirm the speed.
Replacing both pulleys together makes sense
If one pulley is badly worn, the other usually isn’t far behind. Fitting the full set is the cleaner job and helps avoid uneven wear in the cage.
This is a smart fix for noisy drivetrains
Worn jockey wheels can add rumble, chain slop and vague shifting even when the derailleur body is still serviceable. A pulley refresh is often cheaper and tidier than replacing the whole mech.
Upper and lower pulleys are not the same
This set uses a dedicated guide pulley and a dedicated tension pulley. Keep track of which one goes where during install so the derailleur works as intended.
Shimano is a Japanese component brand founded in 1921 in Sakai, Osaka. The company began with bicycle component manufacturing and has grown into a global business focused on bicycle components, fishing tackle and rowing equipment, while keeping its headquarters in Sakai.
In cycling, Shimano is best known for building complete component ecosystems that span road, mountain, gravel, commuting and e-bike use. Its range covers drivetrains, brakes, wheels, pedals, shoes and related parts, and the brand has had a long presence in Australia through a local business established in Sydney in 1992.
