TPU tubes are gaining attention as the third force in bicycle tires. We summarize its features, advantages and disadvantages of using it on road bikes and MTBs, and major manufacturers.
Table of contents
Types of disc brake pads
Types of Materials
There are three main types of disc brake pads: metal, resin, and semi-metal. Which pads can be used depends on the brake caliper and rotor, respectively.
Most of Shimano’s current disc brakes are compatible with both metal and resin pads, but some models are not compatible with metal pads, so be careful when purchasing.
The main difference between metal and resin pads is braking power and squeal.
Metal pads have high braking power and good braking effect, but they are prone to the squeal (metal rubbing sound) characteristic of metal pads, and adjustment is severe. Also, they can be too effective, making fine braking difficult.
On the other hand, resin pads have considerably less braking power than metal pads, but the reduced braking power is more effective and allows for fine braking. Another advantage of resin pads is that they do not squeal as much.
The major choice is based on the braking power of the caliper itself and the combination with the rotor.
Semi-metal pads are made of resin mixed with metal powder and have higher braking power than resin pads, but not as much as metal pads. The braking power of semi-metal pads is not so much “in the middle of metal pads and resin pads” as it is slightly closer to that of resin pads.
|Semi-metal pad||Resin & Metal||○||○|
Types of Shapes
Disc brake pads come in a variety of shapes, and it is basically a prerequisite to use genuine brake pads recommended by the brake caliper manufacturer.
However, Shimano for Shimano, SRAM for SRAM, TRP for TRP, and so on, it does not mean that any pads from the same manufacturer can be used, but be aware that there are cases where the pads cannot be installed due to differences in shape.
In particular, Shimano brake calipers have “narrow” and “wide” pad widths, so you need to pay attention to compatibility.
Disc brakes are designed to be braked by sandwiching a metal rotor between pads, but continuous braking causes the rotor to become hot and braking power to decrease. There are two ways to prevent the rotor from getting hotter: one is to install a heat dissipation mechanism on the rotor side (Shimano’s “Ice Technology”), and the other is to install heat dissipation fins (heat sinks) on the brake pads and calipers.
For example, some of Shimano’s higher-end brake calipers for road and MTB use are equipped with heat-dissipating fins on the brake pads, and when combined with Ice Technology-equipped rotors, this prevents both the rotor and pads from becoming too hot.
However, the availability of brake pads with heat-dissipating fins depends on the caliper brake geometry, so not just any caliper brake can be used.
How to Select Disc Brake Pads
As explained earlier, it is basically best to use brake pads recommended by the manufacturer.
However, if the pads recommended by the manufacturer are not available or if you are dissatisfied with the effectiveness, you may be able to use pads with the same shape.
When using pads that are not recommended by the manufacturer, check three things: material, shape, and cooling function.
How to choose pads when you want to increase braking effectiveness
When you want to improve braking effectiveness, the major choice is to use metal pads when you are using resin pads. However, metal pads are prone to squeal, so simply changing to metal pads does not necessarily mean “better braking performance and comfort. On the other hand, there are cases where the brakes are easier to brake after switching back to resin pads. This is the difficult part of disc brakes.
Even without replacing the brake pads, replacing the rotors can sometimes improve braking effectiveness and squeal. Shimano’s Ice Technology-equipped rotors, in particular, have high heat dissipation performance, which can also affect braking performance.
What to do if disc brakes squeal or make a strange noise?
The following three factors are the main causes of squealing or noise in disc brakes.
- insufficient caliper adjustment
- pads are not hitting
- rotor is deformed
If the pads have been replaced, they may not have been hit, or conversely, if they have been hit, the noise may be heard.
Also, if the rotors have been deformed, the rotors will not rotate straight, which can cause the noise.
Thus, replacing the pads does not necessarily solve the squeal or the noise. Since there are multiple factors such as pads and rotors, it is best to try several brake pads to see where the problem lies.