Inquiries answered Mon to Fri Austin, Texas
+1 (565) 555-2353
Xervilo

Group 04 · Pads, rotors, calipers, levers, bleed kits

We match disc brake pads and rotors to your caliper and your mount, not to a model name you half remember.

Disc brake pads and rotors in 140, 160 and 180 mm, 6-bolt and Center Lock. Rim brake pads for road bike calipers in cartridge form, threaded V-brake pads for flat bars, plus dual-pivot calipers sorted by reach. Levers and hydraulic bleed kits, with the two fluid families kept strictly apart. Sourced for road, city and kids' bikes across the United States from the desk in Austin, Texas.

Disc pad sets from $18 Rim pad pairs from $12 Indicative, confirmed in our reply Quote held 7 days
Send your bike's details Mount standards
  • 140–180Rotor diameters we stock, in mm
  • 2Fluid families, never mixed: DOT and mineral oil
  • 39–57Dual-pivot caliper reach range, in mm
  • 1.5Minimum pad and backing thickness in mm before replacement
  • Post mount 160 mm
  • Flat mount 140 mm
  • IS adapter
  • 6-bolt T25
  • Center Lock
  • Resin pads
  • Sintered pads
  • Cartridge rim pads
  • V-brake 70 mm
  • DOT 5.1
  • Mineral oil
  • Reach 47–57 mm
Two bicycle disc rotors with brake pad pairs on brown leather
Left rotor is 6-bolt, right is Center Lock. The pad shape in front of each one is the part we have to get right.

Item 01

Disc brake pads and rotors

Pad shape is set by the caliper, full stop. There are dozens of shapes in circulation and several look close enough to fool you until the retaining pin will not go through. So we ask for a photo of the caliper from the side, or the old pad laid on a ruler. From that we read the backing plate outline and the pin or clip type, and we send the pad that drops in.

Resin pads are quiet, bite early and wear faster in grit. They suit dry Austin riding and commuters who hate squeal. Sintered pads last longer, cope with wet and long descents, and need a rotor rated for sintered use. Running sintered on a resin-only rotor glazes the braking surface and the bite goes away. Rotors come in 140, 160 and 180 mm, in 6-bolt (six T25 bolts, torque 2 to 4 Nm) or Center Lock (a lockring, usually 40 Nm). Replace a rotor when it drops below the thickness stamped on it, typically 1.5 mm.

  • Pad compoundsResin, sintered
  • Rotor sizes140, 160, 180 mm
  • Rotor fitting6-bolt, Center Lock
  • Wear limit1.5 mm rotor
  • Checked againstCaliper model, mount, hub type

Per pad set or per rotor. Indicative from $18 a pad set, confirmed in our reply.

Dual-pivot road rim brake caliper with spare pad inserts

Item 02

Rim brake pads and calipers

Rim brake pads for a road bike come in two useful forms. Cartridge pads hold a replaceable insert in an alloy shoe, so you set the toe-in once and after that you only slide a new insert in. Threaded V-brake pads bolt straight through the arm with a stack of curved washers; they are the ones on most city and kids' bikes, and the washer order is what people get wrong when refitting.

Compound matters here as much as on discs. Black compound for alloy brake tracks. Cork or a dedicated carbon compound for carbon rims, and never the black one, because it cooks the resin in the rim. If you tell us the rim is carbon we will only quote a carbon pad. Dual-pivot calipers are sorted by reach, the distance from the mounting bolt centre to the pad slot centre: 39–49 mm covers most modern road frames, 47–57 mm covers older and longer-drop frames with fender clearance. Measure yours before asking; a caliper with the wrong reach cannot touch the rim.

  • Pad typesCartridge, threaded V
  • CompoundsAlloy, carbon-specific
  • Caliper reach39–49, 47–57 mm
  • V-brake pad length70 mm typical
  • Checked againstRim material, reach, arm type

Per pad pair or per caliper. Indicative from $12 a pair, confirmed in our reply.

Hydraulic brake lever with bleed syringe attached on a workbench

Item 03

Brake levers and hydraulic bleed kits

Levers split three ways: mechanical levers that pull a cable, hydraulic levers that push fluid, and the drop-bar units that also shift. Cable levers are matched by pull ratio. A V-brake needs roughly twice the cable pull of a cantilever or a road caliper, so a road lever on V-brakes gives a spongy, weak brake that never quite lets go. We ask which arms are on the bike before we send a lever.

Bleed kits are matched to the fluid and the fitting. DOT systems take DOT 4 or DOT 5.1 and the syringes are rated for it. Mineral oil systems take the maker's own oil and a different funnel or syringe thread. We don't quote hydraulic brakes blind. Mineral oil in a DOT system ruins the seals in an afternoon. The fluid type is almost always printed on the lever body or the reservoir cap, so send us a photo of that and the quote comes back the same day.

  • Lever typesCable, hydraulic, drop-bar
  • Cable pullRoad, V-brake
  • FluidsDOT 4, DOT 5.1, mineral
  • Kit contentsSyringes, hose, fittings
  • Checked againstFluid named on the lever

Per lever or per kit. Quoted after the fluid type is confirmed.

Mount standards

Which caliper bolts to which frame

Ordering flat-mount calipers for a post-mount frame is the third most common mistake we see. The two do not interchange in the direction people want. Look at the bolt holes before you order anything.

Disc brake mount standards
MountHow to recognise itRotor sizesFound on
Flat mountTwo bolts entering from under the chainstay bridge, low flat pad on the frame140, 160Road and gravel frames from about 2015
Post mountTwo bolts entering from the side into threaded posts140, 160, 180Forks, many hybrids, older disc road frames
IS (international standard)Two bolts entering from the side into a tab, needs an adapter for any caliper160, 180Older frames and forks
6-bolt rotorSix T25 bolts around the hub flange140 to 180Most hubs, all price levels
Center Lock rotorSplined hub with a lockring140 to 180Shimano-pattern hubs and many wheelsets

Adapters move a caliper up a rotor size on post and IS mounts. Flat mount has far less adjustment, and the frame's stated maximum rotor size is the limit we work to.

Pad compound comparison
CompoundBite when coldWet performanceWear rateBest for
Resin (organic) discStrong, immediateDrops off, fades on long descentsFaster in gritDry commuting, quiet braking, light riders
Sintered (metallic) discNeeds a few stops to warmHolds wellSlower, but wears rotors fasterRain, loaded bikes, long hills
Semi-metallic discModerateGoodBetween the twoMixed-weather commuting
Alloy-rim cartridgeStrongNeeds a wheel turn to clear waterModerateAlloy brake tracks only
Carbon-rim cartridgeSofter initial biteWeakest wetModerateCarbon brake tracks only, never alloy

Disc pads and rotors bed in together. Fit new pads to a worn rotor and the bite stays poor until the pad wears to match, which can take 30 or 40 hard stops.

How a brake inquiry runs

Four photos and we can quote the whole brake

  1. Photograph the caliper from the side

    That shows the mount type, the pad retaining pin and whether it is hydraulic or cable. If it is hydraulic, include the lever and reservoir cap in a second shot so we can read the fluid.

  2. Read the rotor

    Diameter is usually etched on the arm, along with a minimum thickness. Tell us whether the hub has six bolts or a splined lockring.

  3. For rim brakes, measure the reach

    From the centre of the mounting bolt to the centre of the pad slot, in mm. Also tell us whether the rim is alloy or carbon. That single answer changes the pad compound entirely.

  4. We reply within one business day, Mon to Fri

    Every line in the reply carries the checks we ran: caliper model, mount standard, rotor fitting, pad compound, fluid. Indicative prices sit in a column beside them and the total holds for seven days.

  5. You confirm, we bag and tag

    Pad sets go out with their springs and pins in a tagged bag. Rotors ship flat with the correct bolts or lockring.

What we will not do

Where we stop

  • No hydraulic quote without the fluid named. Not a guess from the model, not "it's probably mineral". A photo of the lever or the reservoir cap, or we wait.
  • No caliper into a mount it does not fit. Flat mount to post mount is not an adapter job in that direction, whatever a forum says.
  • No black alloy compound on carbon rims. We will refuse it even if you ask for it by name.
  • No rotor bigger than the frame or fork is rated for. The maximum is printed near the mount or in the maker's spec, and we work to it.
  • No bleed service. We ship parts. We do not work on your bike.

Who this page is not for. If you ride downhill or trail, you want four-piston calipers and 200 mm rotors, and that is not what this desk keeps. We cover road, city and kids' bikes. If you are not sure which side of the line your bike sits on, call and ask before you send a list.

Contamination. Oil on a pad is permanent. Degreaser, chain lube overspray, a leaking seal: once it soaks into resin, the pad is scrap. Sintered pads can sometimes be burned clean with a torch, resin cannot. If one wheel squeals and the brake feels weak, replace the pad rather than cleaning it.

Common questions

Brake questions that come in every week

Resin or sintered?

Resin if you ride mostly dry and want quiet. Sintered if you commute through rain, carry panniers, or descend long enough that the rotor gets hot. Check the rotor is rated for sintered first; many lightweight road rotors are resin only and it is printed on the arm.

My brakes squeal. Do I need new pads?

Usually it is contamination or a caliper that is not aligned. Clean the rotor with isopropyl alcohol first and re-centre the caliper. If the squeal survives that and the braking is weak, the pads are contaminated and new ones are the fix.

Can you supply pads for my kid's 16 inch bike?

Yes, where it has a rim brake. Most small bikes use short threaded V-brake or side-pull pads, and some run a coaster brake in the hub with no pads at all. Photograph the rear hub and the brake arm. More on that in kids' bike parts.

How long should a set of pads last?

Too many variables to promise a mileage. Resin disc pads on a dry commute often go a season; the same pads through a wet winter can go in six weeks. Measure instead: when pad and backing together are under about 1.5 mm, order new ones. We put the measurement in the reply so you know what to look for.

Do you fit the parts?

No. This is a parts desk, not a workshop. We supply the right part with the checks written next to it; the wrench is yours or your shop's. Returns on a wrong-fit part are covered in warranty and returns.

Send a side-on photo of the caliper. That is most of the quote.

One business day reply target, Mon to Fri. Indicative prices held for seven days once we reply.

Send your bike's details

Nearby in the catalogue

Tyres and tubes Wheels and hubs Cables, housing and fluids Drivetrain parts Road bike parts City bike parts Compatibility checks