You almost never need to replace an entire drivetrain. A missing bolt, a cracked cover, a spacer lost during disassembly: this range brings together the parts manufacturers sell individually, saving you from buying a complete component.
Crankset components
Left crank arm bolts and safety plates Shimano — the small part that holds the crank arm in place if the bolt comes loose.
Clamp bolts M6x19 and M6x21 with a washer, depending on the generation.
Chainring bolts and complete kits, particularly for Rotor cranksets and Campagnolo Ultra-Torque setups.
Lever components
Front covers left and right, with their bolts, for the ST-R7020, ST-R8000, ST-RX600 and 4720. These are the first parts to take the impact when a bike falls on its side, and replacing them saves you from buying a complete lever.
Derailleur components
Cable pinch bolts, tension adjustment screws, derailleur cage inserts and cage plates for front derailleurs.
Charging port covers and protective hoods for recent Di2 derailleurs — RD-R7150, RD-R8150 and RD-R9250.
Clamp shims SM-AD91 to adapt a front derailleur clamp from 31.8 to 28.6 mm.
Cassette components
The spacers in 0.5, 1.0 and 1.85 mm thicknesses make up the difference between an 11-speed freehub body and a 10- or 12-speed cassette. This is the part most often missing when changing wheels; DT Swiss and Shimano offer dedicated versions.
How to find the right part
The best way to identify these parts is by their manufacturer’s part number — such as Y0F498010 — much more reliably than by their description. It appears on the component’s exploded diagram published by the manufacturer.
