https://bike.shimano.com/en-US/information/news/brake-pad-breakdown-metal-versus-resin-pads--what-you-need-to-kn.html
Brake Pad Breakdown Metal versus Resin Pads: What you need to know
When dropping into a steep and technical trail or zipping through paved switchbacks in a tightly packed peloton, the last thing any rider wants to be questioning is their brakes. For many cyclists – road, mountain, gravel, or cross – brake pads are one of those components that don't get much love. They're taken for granted, and we assume they'll work just fine when we need them. Thankfully, for the most part, they do. But, depending on where, when, and how you ride, choosing the right type of disc brake pads — metal or resin — can make a big difference in your on-bike experience.
So, what’s the difference between metal and resin brake pads, and what are the benefits of each? How should you choose which type is right for you? Here are answers to all those questions and more.
Metal versus Resin
Resin brake pads - also referred to as organic or semi-metallic pads - are made from a mix of fibers held together by resin. Typically, those materials are softer than their metal counterparts, which usually means they are quieter when braking.
Metal brake pads, meanwhile, are sometimes called metallic or sintered, and you guessed it, are made from metallic particles fused together. Metal brake pads are often used for OEM spec, meaning that’s what you’ll go home with if you buy a new bike from a bike shop. This is due to metal brake pads' versatility and their ability to perform in a wide variety of conditions. This is also why you’ll find metal brake pads on most cars and motorcycles.
Weather considerations
Whether you're a mountain biker, road rider, gravel grinder, cross racer, or e-biker, the primary reason to go with metal brake pads comes down to precipitation. If you live in a location where rain is a frequent riding companion, like the Pacific Northwest, for example, then metal pads are likely your best choice. Metal pads last far longer in rainy and wet conditions than their resin counterparts. You'll end up saving money throughout the season with metal brake pads because you won't need to replace your brake pads every few rides like you would with resin.
Noise reduction
If there's one thing that most cyclists can't stand, it’s a noisy bike. And few components can generate more racket than a malfunctioning set of disc brake pads. Heat, moisture, dust, and other contaminants can cause brake pads to squeal. Metal pads are more susceptible to this squeal than their resin brethren.
If you spend most of your ride time shredding dusty mountain bike trails or live in a dry climate, resin brake pads could make you a lot more popular with your riding pals, because no one likes to ride with that guy with the constantly screeching brakes.
Bite and modulation
Metal and resin brake pads feel slightly different in their power delivery and modulation. Deciding which type of pad is right for you comes down to personal preference. Some riders prefer the on-off, near-immediate bite of metal brakes pads. Others lean toward resin’s more modulated feel, which allows you to ramp up power at a more measured pace.
Different types of terrain and your riding style can help decide what pad is best for you. For example, if you ride a gravel bike and are concerned about locking up your wheels on a loose fire road, the enhanced modulation of resin brake pads may give you more control. Conversely, if you’re pedaling a road bike on smooth pavement where traction is typically less of an issue, metal brake pads will likely work just fine — and won’t wear out as fast.
Power, heat management, and fade resistance
When it comes to raw stopping power and heat management, which helps reduce brake fade, metal brake pads are typically your best choice. So, if you're contesting a super steep enduro mountain bike race, or bombing around on a portly e-bike, metal pads are less likely to fade or lose power due to heat buildup.
Shimano ICE-TECHNOLOGIES brake pads feature an innovative finned-design to help manage and reduce heat buildup. Available with both metal and resin brake compounds, these brake fins have a two-layer aluminum and stainless steel construction. Together, these elements provide rapid heat diffusion, which lengthens maintenance intervals, provides longer pad life, and reduces brake fade and noise while riding.
Mix it up
Still can’t make up your mind? Well, it turns out that you don’t have to. Some of the top professional racers in the world, including some members of the famed Santa Cruz Syndicate downhill mountain bike team, often run mixed brake pad set-ups. The idea is that since the inner brake pad typically wears quicker than the outer, you run a metal brake pad on the inside and resin on the outside. This allows riders to reap benefits of both the materials while minimizing drawbacks.
https://bike.shimano.com/en-US/information/news/brake-pad-breakdown-metal-versus-resin-pads--what-you-need-to-kn.html