Most brands of brake are not going to offer their best performance once the disc brake pads material reaches 1.5mm or less in thickness.
How quickly that happens depends on the sort of riding you do and the conditions in which you ride, as well as the composition of the braking material.
Wet and dirty or sandy and gritty conditions will wear pads much quicker than clean dry conditions – if doing a particularly long ride you may even need to take a replacement set with you and change them during the ride.
More extreme riding, such asdownhill mountain biking, or been on an E.Bike will wear through pads more quickly than regualar cross-country mountain biking or general road riding.
You can also get uneven pad wear if they’re not aligned correctly with the rotor – or they might rub the rotor when not in use.
When it comes to pad wear, you definitely don’t want to reach the point where there’s metal-on-metal contact between the pad’s support and the rotor because this will not only reduce braking performance but also quickly damage the rotor.
Disc brake pads come in a range of shapes and sizes to fit different brake models, so using the correct fitting pad is critical to correct operation of your brakes.
But there’s more to pad choice than that because pads can be made from a range of different materials. The best option for you depends on the type of riding you’re doing.
Pads can be either organic, sintered or semi-metallic, below decribes the differances between the materials..
Organic disc brake pads
Organic disc brake pads are generally made up of Kevlar, rubber and silica, bound together with resin.
Also referred to as resin pads, they’re the quietest option. They also give you sharper low speed braking and don’t need to warm up before they start to work well.
The organic compound helps to insulate the pad from the caliper, so more heat stays in the rotor and less is transferred to the brake fluid, although they’re more prone to fade under prolonged braking.
An organic pad will also wear out more quickly than other options as it is softer, so you’ll need to change your pads more frequently. If you ride in wet or gritty conditions they may not be the best choice, they can glaze over from prolonged brake use to, so you might need toremove the pad from time to time and scrub the surface up with some wet and dry paper.
Organic pads are a good option for less extreme riding in dry conditions, so they work well for summer use onroad bikes with disc brakesand XC mountain biking, particularly if you live somewhere relatively flat and aren’t riding technical descents with lots of braking.
Pros- Sharper initial braking response
- Quick to bed-in
- Excellent initial bite, especially at low temperatures
- Quieter
Cons
- Faster wear
- Degraded performance and faster wear when conditions are wet or dirty
- Braking power fades at high temperatures
- Can glaze over
Sintered disc brake pads
Sintered, or metallic, brake pads are made of a mixture of metallic particles pressed together.
They are more durable than organic pads and should last longer because they can handle dirt and damp conditions a lot better.
Sintered brake pads will keep working well at higher temperatures too, although the metal content tends to transfer more heat to the brake fluid in the caliper than an organic pad.
However, sintered brake pads need a while to warm up before they start to work at their best and are also much more likely to be noisy.
Sintered disc brake pads are a good option if your riding is on the more extreme or higher speed side, such as downhill orenduro mountain biking, or if you frequently ride in muddy conditions.
Pros- Longer lasting
- Strong stopping power under extreme braking
- More consistent in wet and dirty conditions
- Can handle higher temperatures
- Not prone to glazing
Cons
- Take longer to bed-in
- More prone to transfer heat to calipers
- More likely to be noisy
Semi-metallic disc brake pads
Semi-metallic pads look to combine the advantages of both organic and sintered brake pads.
They’re made of an organic compound but incorporate metal particles to increase durability.
Other advantages include better ultimate stopping power than organic pads on long descents paired with quicker warm-up than sintered.
Like organic pads, they’re prone to glazing and they’re often the most expensive option. They’re not as quiet as organic pads either.
They’re a good all-round option for E.bikes, road riders and XC mountain bikers because they’ll work well in the wet or dry, without sacrificing too much longevity.
Pros- More durable and better wet-weather performance than organic
- More predictable power than sintered pads
- Don’t take as long to warm up as sintered
Cons
- More expensive than other options
- Can be prone to glazing
Swapping pad compounds
It can be worth experimenting with pads and pad composition, rather than just replacing like with like. You might want to change pads between summer and winter too, opting for the increased power and quieter performance of organic pads in the summer, and the durability of sintered in the winter.
You can also mix-and-match brake pads, using a longer-lasting sintered or semi-metallic pad at the rear and an organic one at the front. Though don't mix pads in the same brake caliper!
The organic front pad will give you more stopping power, but at the expense of greater wear. Rear brake stopping power doesn’t need to be as great as at the front and the harder pad should last longer and be more weather-resistant.
For optimum performance, when you change pad compounds you could also upgrade brake brake rotors too as some rotors may only be rated for a resin pad use. You should also always scrub the brake rotor surface before running new pads to ensure the old material is not affecting the new pad performance.
Remember to then 'Bed' the new pads onto your rotors before needing to actually use the brake to stop!
The way to bed the pad is can be done by riding your bike some where there are no hazards and the need to stop quickly. Whilst pedalling the bike around pull the brakes on 40-50 times and pedal against the resisantance, pulsing the brakes on and off to allow the pad and disc start working as a system.
Other factors to consider
It’s also worth considering the backing material used on brake pads. You may not have a choice in this, but some brands make pads with either alloy or steel backing plates – the former saving you a couple of grams and sometimes coming with claims of better heat dissipation. Even titanium-backed pads are available from some manurfactures, most notably with Shimano’s XTR brakes.
It’s also increasingly common to see disc brake pads with built-in cooling fins, popularised by Shimano with its Ice-Tech pads and said to improve braking performance by using airflow to quickly move heat away from the pad surface.