FRICTION IS YOUR FRIEND
BRAKE PAD AND ROTOR CLEANING TIPS & TRICKS
Tech Tuesday Presented by TRP
Wondering why your mountain bike’s brakes aren’t feeling as good as they used to? Looking for the best solution to cure contamination or fade? Or are you just looking to make your brakes work powerfully and reliably as they can for as long as they can? We sat down with TRP, World Cup racer Neko Mulally and TRP’s lead engineer Colin Esquibel to give you some tips on cleaning and maintaining mountain bike disc brakes. If you don’t like to read, just check out our in-depth YouTube video and please be sure to subscribe as we’re really trying to grow our channel! Enjoy.
Brake rotors are available in a range of diameters, from weight-weenie approved 140mm discs to monstrous 223mm units that are appropriate for stopping a tank. A larger rotor will add weight overall, but at The Loam Wolf we’d always err on the side of bigger is better. The increased control and confidence in your brakes at the end of a long descent pays dividends. It’s important to make sure your bike will accept a larger rotor and you won’t void any warranties, but it’s one of the simplest upgrades you can make to your stoppers.
Rotor thickness is something that’s often overlooked, but it can make a big difference. Standard rotors are 1.8mm-2mm thick, whereas TRP brakes use a thicker 2.3mm rotor. This not only lets the rotors handle and dissipate the heat a little better, but makes them much less prone to warping or bending. Again, we like to opt for thicker rotors where possible, but it’s important to ensure your brake caliper will accept some of the thicker units.
Brake Pad Material
Depending on the brand, there are usually two or three options for brake pad materials. The standard options are Metallic (Sintered), Semi-metallic (Hybrid material) or Organic (Resin). The resin pads will deliver a softer, more delicate lever feel upon initial pad contact to the rotor, making them the choice for World Cup downhill superstar Neko Mullaly. Once up to temperature, the initial bite is awesome on resin pads, however they can be more susceptible to heat fade, don’t work as well in wet, and don’t last as long as the alternatives.
Metallic pads solve some of the issues from the resin option, however they are louder, slightly more “harsh” in their initial pad contact with less ramp up, and have less initial bite when hot. They resist heat fade a lot better and last a lot longer though, especially in wet, gritty, or sandy conditions. The folks at TRP, and our own personal experience suggest that if you’re a heavier rider or someone who’s on the brakes a lot, metallic pads are the way to go.
Semi-metallics strike a middle ground between the two, not quite reaching the bite levels of a Resin pad nor the longevity of the Metallic. What they do however is blend some of the bite, and lever-feel traits with longevity and heat management. Not quite the best of both worlds, but a good all-rounder.
When it comes to braking, friction is your friend! It’s essential to be very cautious when handling, washing and lubing your bike and to ensure any products that find their way onto the braking system don’t contain any lubricating ingredients like silicon.
Colin Esquibel at TRP won’t even touch a brake rotor with his bare hands, you really don’t want to risk the residue of your Cheetos or natural oil finding its way onto your brakes. TRP and TLW recommend only using Isopropyl alchohol or IPA for brake cleaning as it leaves behind no residue and is safe on o-rings and seals. A spray bottle is particularly useful here to help get it into hidden areas. Isopropyl is probably the cheapest and best hack to keeping your brakes running stronger longer! Use it!
Another thing to consider is your driving situation when transporting your bikes. If you’re carrying your bikes outside your car or truck, driving in the wet, through snow and de-icer, or dried dust, all this crud will cause issues. The debris will fly up onto your rotors and pads, and when you start your first downhill the contaminants will bake into the pads and rotor and ultimately lower friction and overall brake performance. Consider adding a cover to the brakes to keep them safe. Something like Muc-Off’s rotor protectors are a great option, but if you’re budget minded, Neko says he used to use Shower Caps from the .99 Cent store. Also a great reason to carry a spray bottle of Iso. Get to the trail, pull our your sprayer and a rag, and clean all that road gunk off your brakes.
If you’re starting to feel a lack of bite in the pads or they’re making noise, it’s worth popping the pads out and refreshing the braking surface. This is as simple as sanding off the top surface of the pads, which may be glazed or dirty, to reveal the fresh pad surfaced below. Colin at TRP recommends drywall sandpaper for brake pad sanding, as it has holes that let old pad material fall through, preventing it from being rubbed back into the pads. Rubbing the pads face-down onto a piece of sandpaper using a figure of 8 movement, you can quickly reset the pad surface – just keep on sanding on a flat surface until you get a uniform brake surface without the shine of a used pad. If there is oil on your pads or disc, you’ve got to throw away the pads as the oil will seep into the pores and it’ll leach out no matter the cleaning you do. You may clean them and find they feel good initially, but after a few hard braking efforts this oil will find its way onto the braking surfaces again, so be safe and chuck them.
Resurfacing brake rotor is a similar process to the pads but can be done with the rotors still mounted to the bike. It’s always a good idea to check your caliper and rotor bolts are torqued adequately, as a loose brake can spell disaster, or annoying vibrating harmonics. You’ll want to start by wiping them off with some Isopropyl alcohol on a rag. Then take some steel wool with some IPA, and go around the rotor rubbing away any baked in dirt and debris, until you’re left with a renewed, cleaned braking surface. Give the rotor a final wipe with a rag and IPA to make sure it’s as clean as possible, and you should be good to go. At the World Cups, Colin will go so far as to blowtorch the rotor to burn off any remaining steel wool, rag etc. Overkill perhaps for the average joe, but a sure-fire way to ensure the rotor is as clean as possible for his team riders.
IMPORTANT STEP – Once the pads and rotors are resurfaced and cleaned, it’s time to bed in the rotors and pads again before hitting the trails, give this a watch for bed-in tips. After a few minutes getting the rotor surfaces primed for some hard braking, you can enjoy your stoppers that should now be feeling damn good.
TRP kindly provided us with their essential DO’s and DON’Ts list, which even taught us veterans a thing or two, and will hopefully keep us from ever re-living the PTSD-inducing times running old Hayes and Avid brakes back in the day.