Which disc brake pads are best for mountain bikes? Sintered or organic?
When it comes to replacing your disc brake pads, there are a staggering number of different brands and types to pick from. Our guide will run you through what you need to know, covering sintered and organic pad compounds and their relative strengths and weaknesses so you can get the best disc pads for your needs.
- The best mountain bike flat pedals ridden and tested
- Your complete guide to the RockShox fork range
- Buying your first mountain bike: the complete guide
[Updated 21st June 2021]
When it comes to replacing your disc brake pads, the first thing you need to do is make sure you get the correct fitment for your brakes. There are a dizzying number of different styles available, so don't think that all Shimano or SRAM brakes will use the same pad - they don't. For example, there are numerous different pads for Shimano XT brakes, depending on which year they were made.
How do I know which pads I need?
If you know the exact model and year of your brakes, then this is a good starting point, but the best way to know if new ones will fit to remove the old ones and visually compare them - you're going to have to do this anyway if they're worn out, so it's no great hardship.
How to remove disc brake pads
To remove the pads, first, remove the wheel and then clean the calliper with disc brake cleaner and then wipe it clean with a clean rag or tissues. You will then need to push the pistons back - worn pads are thinner than new ones, and hydraulic systems automatically push them out to compensate. Skip this step, and you'll struggle to get the disc and wheel back in with the new pads.
There are specific tools for pushing pads back, and some multitools will have something too, but using a large, flat-bladed screwdriver or tyre lever carefully achieves the same thing. Pop it in between the pads where the disc would sit and gently lever them back until they go no further. You'll need to adjust either cable tension or a pad advance adjuster on cable systems, depending on the model.
Most disc brake pads are secured in place by a pin that sits through a hole in both pads, often with a retaining clip on one end to prevent them from falling out. Remove that and then unscrew or otherwise remove the pin. Make sure you don't lose these, as aftermarket pads often come without them.
Now's a good time to inspect the pads you're taken out too - if they're not evenly worn across the pad, then your calliper is out of alignment, and if one side is more worn than the other, then you have a sticky piston. Both of those issues will need fixing before you stick some new pads in.
Suppose they've worn down to the metal backing pad. In that case, you should carefully check your rotor for scoring damage - and if they've worn through the backing pad too, then shame on you for not noticing. It'd be wise to inspect the pistons for damage also. If you've been through lots of pads on the same rotor, check that the rotor isn't excessively thin. Check the manufacturer's guidelines on minimum thicknesses.
What do the different pad compounds mean?
All pads are made by mixing various powdered additives with a binding agent and then squashing it all together at high heat and pressure to form a solid block on the backing pad. What's in the mix of powders has a drastic effect on the pad's properties. There are three main types of disc brake pad compound for bikes.
Also commonly known as resin pads, these are the usual fitment on most new bikes. These brake pads are made from non-metallic additives such as rubber, glass, carbon and Kevlar to provide an all-around pad that works but isn't very durable under hard use.
|Excellent bite from cold||Friction decreases at high pad temperatures|
|Very little braking noise||Pads wear quickly|
|Slow rotor wear|
Also known as metallic brake pads, these use a very high proportion of metallic fillers such as copper, steel and iron. They're made for work best under extreme use condition, so often aren't the best choice for general riding.
|Strong, effective braking at high pad temperatures||Can be noisy|
|Slow pad wear rate even in poor conditions||Poor bite when cold - need to be hot to work well|
|Metallic content can transfer more heat into the calliper, potentially overheating the fluid|
|Faster rotor wear|
As the name suggests, these have metallic fillers mixed with organic fillers to give a balance of the qualities of each. They're a bit of a Goldilocks option, so they're suitable for anyone that wants increased hard-use performance over an organic pad without the drawbacks of a sintered pad. But, on the flip side, they retain some of the drawbacks of each, too.
|Better high-temperature performance than organic pads||Composition - and performance - can vary wildly from brand to brand|
|Less noisy than sintered pads||Don't have the same ultimate high-temperature performance as sintered pads|
|Decent bite from cold||Noisier than organic pads|
So which brake pads are best?
As with many things in life, it really comes down to what sort of riding you do and where you'll be willing to compromise.
If you live somewhere flatter or just don't throw yourself down huge descents all that often, there's nothing wrong with an organic pad. They'll provide strong braking from the moment you pull the lever while being quiet and often cheaper than the other options too.
If you often ride long, sustained descents with lots of braking or ride somewhere gritty and wet and wear out pads regularly, then sintered pads are a wise choice. If You don't mind the noise, they're powerful and have plenty of bite once they're warm and last for a long time.
Semi-metallic pads are an excellent compromise, with a decent bite from cold, respectable high-temperature performance and good wear characteristics.
Of course, nothing is stopping you from mixing and matching brake pads front to rear to suit your needs. Rear brakes tend to be dragged more while having a good initial bite at the front is always confidence-inspiring. A sintered pad at the rear paired with a semi-metallic compound in the front can offer a good blend of performance, even semi-metallic at the rear and organic at the front.
But what about finned brake pads?
Shimano introduced their Ice-Tech brake pads in 2015. These have a backing plate with a finned heat sink that protrudes from the top of the calliper. It's claimed to improve performance as the heat generated under braking is dissipated by airflow more quickly, resulting in lower temperatures at the braking surface and calliper body, giving a consistent performance.
Initially, these pads were only available for specific Shimano brakes, but several aftermarket manufacturers have taken the idea and applied it to pads for other brands. Superstar Components, Uberbike Components, Swiss Stop and some others all have designs like this. While some have laboratory testing to back up their claims of cooler running, most do not, so it's worth taking these claims with a pinch of salt - especially as they're a fair bit more expensive than standard pads.
You're quite right that isopropyl alcohol is the right stuff to be using, but having a bit of aerosol power behind it is a boon if you're a bit lazy..
Good shout on the tyre levers too!
"claimed to give improved performance as the heat generated under braking"
Well, they do work, and I learned that in practice! My ingenius LBS, replaced my road bike's ice-tech pads, with standard ones and I didn't notice. After suffering several rides with horrible brake fading, the pads and the metal spring between them melted and became one piece. Also the calibers look like burnt and their paint chipped off. I am lucky I didn't get any frame damage (i hope!).
Ever since this incident, I trust my bike to no LBS, and I got ice-tech pads for all my MTBs too!
Highly recommended cheap upgrade
"clean the calliper with disc brake cleaner"
Hayes say "Clean the disc and the hub-mounting surface with isopropyl alcohol (not disc brake cleaners)." I think it's because disk brake cleaners can have additives in. Just stick with isopropyl alcohol, it's the major constituent of disk brake cleaners anyway, and probably a lot cheaper.
Also plastic tyre levers are really good for levering pistons, particularly phenolic ones which can chip easily with a sharp thing like a screwdriver.