Which disc brake pads fit, and how to swap them

When pads need changing

Brakes squeal or grind, or stopping power has dropped

Shimano says noise while braking can mean the pads are at the wear limit. Let the brakes cool, take the pads out and measure them against the limits below.

Brakes feel weak and the lever is firm

Check for oil on the pads or rotor. Pads that have touched oil must be replaced. See oil on the pads or rotor.

The pad spring is touching the rotor (Shimano)

Shimano says to replace the pads when this happens, whatever their thickness.

The lever is soft or comes back to the bar

That is usually air, not pads. See the bleed page. On SRAM DB8, if lever travel grows as the pads wear, the DB8 troubleshooting has a quick fix.

New pads rub or the brake is weak after a pad change

Re-center the caliper, and bed the pads in properly. Braking gets stronger during bed-in.

You want more stopping power (SRAM)

SRAM suggests a bigger rotor, HS2 rotors, a different pad (organic bites harder, sintered lasts longer and works better in the wet) and a proper bed-in.

Which pads fit your caliper

The caliper model number is on the caliper body. These are the pads listed for each caliper in Shimano's exploded views and product pages and in SRAM's spare parts catalog. Do not assume a pad fits because it looks close.

Shimano's exploded views list two part numbers for most pads, for example EBPG05ARXA and Y2R298010 for a pair of G05A-RX. Some pads, such as G05A-RX and B05S-RX, also come in 25 and 50 pair shop packs. SRAM's DB8 H-spring (large, two in a pack) is 11.5018.006.003.

Tiagra 4700 uses BR-4700 rim brakes with one-piece R50T5 or R50T4 shoes, not disc pads. Shoe replacement and toe-in are on the Tiagra 4700 brake section.

Pad and rotor wear limits

Shimano and SRAM measure pad wear differently. Shimano measures only the pad material. SRAM measures the pad material and the backing plate together.

All of them: replace pads that have touched oil, whatever their thickness. SRAM also advises fitting a new rotor when you change pad material, for example organic to sintered.

Change the pads

The order is the same on every caliper here. How the pads are held in, how you push the pistons back and the torque figures differ; see model differences and follow your model page for the exact steps.

Before you start: do not touch the pad surface or the rotor with oily fingers, and do not squeeze the lever with the wheel out and no spacer fitted, or the pistons will push out too far.

1. Remove the wheel.

2. Remove whatever holds the pads in: the split pin (MT200), the retaining clip and pad axle (XT, 105, CUES) or the e-clip and pad retainer bolt (DB8). Take out the pads and the spring.

3. Measure the old pads against the wear limits, and check for oil.

4. Clean the pistons and the area around them. Do not put oil, grease or brake fluid on the pistons.

5. Push the pistons straight back as far as they go with a flat tool, without twisting. Never use a sharp tool. On XT, 105 and CUES levers, fit the oil funnel to the lever bleed port first, so the oil pressure does not damage the lever diaphragm. The pistons self-adjust as pads wear, which is why they have to be reset.

6. Fit the spring between the new pads. Shimano springs and finned pads have L and R marks; fit them the way they are marked.

7. Slide the pads in and fit the split pin, pad axle and clip, or retainer bolt and e-clip. Tighten a pad axle or retainer bolt with a torque wrench to the figure in the table below.

8. Fit the pad spacer and pump the lever until it feels firm. Remove the spacer and refit the wheel.

9. Spin the wheel and check the rotor does not rub. If it does and the wheel is seated properly, re-center the caliper: loosen the caliper bolts, squeeze and hold the lever, and tighten them with a torque wrench (Shimano 6–8 N·m, SRAM DB8 9.5 N·m).

10. Squeeze the lever hard. It must be firm and stop well short of the bar. Then bed in the pads.

    From Shimano DM-MBBR001, DM-MADBR01, DM-RADBR10, DM-LADBR01 and the SRAM DB Brakes Service Manual, brake pad replacement

Model differences

The 1–1.5 N·m pad axle figure for BR-R7170 comes from a label in a figure in DM-RADBR10. The BR-R9270 in the same figure uses 0.2–0.4 N·m, so make sure you read the right row. The full step lists are on each model page: 105 pads, DB8 pads, XT M8100, MT200, CUES.

Bed in new pads

New pads, and new rotors, need bedding in before they reach full power. Do it on a flat, safe area away from traffic, one brake at a time.

• Shimano MT200 and XT M8100 (Shimano user's manual UM-8VR0A): ride while holding one brake lever just enough that you can still pedal, for 20 m, then let go. Do this at least 10 times for each brake. Shifting to the largest sprocket and smallest chainring makes it easier. On an e-bike, turn the assist off. Resin pads take longer to bed in than metal pads.
• Shimano 105 BR-R7170 and CUES: accelerate to a moderate speed and brake to walking pace, one brake at a time, at least 20 times per brake.
• SRAM DB8: about 20 firm stops from a moderate speed to walking pace, then about 10 very firm stops from a faster speed to walking pace. Stay seated, never lock the wheels, and let the brakes cool afterwards. SRAM warns the bed-in needs heavy braking and can cause a crash if you lose control.

Braking force keeps rising through the bed-in. Check for rub afterwards and re-center the caliper if needed.

Oil on the pads or rotor

Contamination: pads that have touched brake oil or grease cannot be cleaned and must be replaced. Wipe oil off the rotor with isopropyl alcohol. Do not use commercial brake cleaner on Shimano brakes; Shimano says it damages the seals.

Take the pads out before any bleed, as both Shimano and SRAM tell you to. If oil keeps appearing at the caliper or lever, find the leak before fitting new pads, and have a bike shop check the brake if you cannot find it.

Related: Bleed mineral oil brakes, SRAM DB8, Shimano XT M8100 brakes, Shimano MT200 brakes, Shimano 105 R7100 brakes