Brake Pads - Sintered Vs Organic

While there are a multitude of unique brake pad formulations available for performance motorcycle applications, most can be filed into one of two basic categories: sintered metal, or organic. In the following paragraphs, we'll examine the properties these pad types have in common, the differences that set them apart, and the uses we feel best suited to each. Keep in mind, however, that these are very broad generalizations. No two pads are the same, and with racing pad manufacturers such as Ferodo, Vesrah, and Performance Friction, constantly upping the bar by combining the best traits of each, lines that used to be clear and distinct are now starting to blur.

Sintered Metal Brake Pads

Sintered metal pads are probably the most common of the two basic types, and are most likely what came came on your bike as original equipment. Sintered pads are characterized by the incorporation of metal flakes or powder into the pad compound. A variety of metals are used, either alone or in combination, including (but not limited to) brass, iron, and bronze. The bulk of the pad material - the 'binder' - is generally one of the many combinations of material used in pure organic pads. In fact, sometimes the only difference between a manufacturer's sintered and organic offerings is the addition of metal. The percentage of metal to binding material varies greatly from one pad to another, though the trend in motorcycle pads seems to be shifting away from pads with extremely high metal content, reducing brake noise, and minimizing rotor wear.

Some properties shared by many sintered pads include:

• Operating Temperature - In most cases, sintered metal pads run at significantly higher temperatures than their organic counterparts. This is not a problem in and of itself, but if you happen to be suffering from heat related issues with organic pads - to include excessive brake fade, rotor warping, or distortion of the brake pads' back-plates - switching over to sintered pads may very well make your problems worse. Conversely, if you suffer from heat related issues running sintered pads, switching over to organics might make enough of a difference to minimize, or even solve the problem without resorting to more drastic measures.
  
  
• Rotor Wear and Compatibility - Generally speaking, sintered metal pads wear brake rotors faster than organic pads, due to their relatively abrasive nature. In many cases, however, especially with some of the newer sintered compounds on the market, the amount of additional wear isn't significant, particularly when used on stainless steel rotors. When used with iron rotors, this abrasive nature, combined with higher interface temperatures, can sometimes cause problems - to include premature wear, rotor warp, and galling of the swept surface. We strongly recommend that anyone running ductile iron / gray iron rotors first consult their rotor manufacturer before considering a switch to sintered metal pads.
  
  
• Feedback - While sintered pads can generate strong braking power and 'initial bite', they sometimes do not provide the feel, progressiveness, and feedback that organic pads can. Some sintered pads are particularly 'digital' in nature, feeling as though they're either 'on' or 'off'… with not much in-between. However, not all sintered pads fit into this mold, and many of the newer sintered compounds we've tried (and sell) come close to rivaling their organic counterparts in this regard.
  
  
• Stopping Power - Sintered metal pads usually provide excellent stopping power in dry conditions, and often exceed the performance of organic pads in the wet. Sintered pads also tend to provide a flatter torque curve across their temperature range, making them great candidates for use on street motorcycles, where operating temperatures vary widely, and predictable stopping power is desired straight out of the driveway.
  
  
• Bed-in - The bed-in procedures for sintered-metal brake pads are usually quick and uncomplicated. In fact, many manufacturers advertise their pads as requiring no initial bed-in whatsoever… just 'mount and ride'. While we personally feel that all new pads should be bedded-in to assure maximum performance, there's no doubt that sintered brake pads are much more forgiving in this regard.

Organic Brake Pads

Back-in-the-day, organic pads were known for two things... less-than-stellar performance, and asbestos. Today - organic pads are putting racers on podiums worldwide - without relying any well-known carcinogens.

In the context of this article, 'organic' is a broad term, encompassing pads that utilize ceramic, kevlar, carbon, fiberglass, natural and synthetic rubber, and other nonmetallic fibers in their construction. These fibers, alone or in combination, are basically combined and formed with a variety of filler materials and high-temperature resins. Due to the wide range of materials used in construction of organic pads, the characteristics of any two pads can differ greatly. There are, however, some properties common to most:

• Operating Temperature - Organic brake pads usually operate at substantially reduced surface interface temperatures compared to sintered. For this reason, bikes suffering from brake fade or other heat-related problems may benefit from these cooler running pads.
  
  
• Rotor Wear and Compatibility - Organic pads are typically very kind to brake rotors, due to cooler operating temperatures and reduced abrasiveness. Most organic pads are safe to run on iron and stainless rotors alike.
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• Feedback - Organic pads generally provide excellent feedback at the lever, coupled with a progressive initial bite that lends well to delicate braking when on the edge of traction. This progressive nature also makes organic pads somewhat more forgiving of aggressive lever input.
  
  
• Stopping Power - In the past, many organic pads suffered from an overall lack of stopping power, compared to sintered variants. While this reduced stopping ability still characterizes a handful of lower-grade organic pads, the better race-bred organics available today give up little, if anything, in terms of clamping ability. However, most organics do still require some heat in the pads to function optimally, which may make them unsuitable for some street applications.
  
  
• Bed-in - Organic pads typically call for a short bed-in procedure after initial mounting in order to assure optimum performance. It is also recommended that brake rotors be completely cleaned of old pad material and properly surfaced before mounting new pads, particularly when switching from sintered pads. While these bed-in procedures aren't complicated or difficult, significantly-reduced performance may result from not following through with them before putting organic pads into service.

Our Recommendations

• Race or Track-Only Motorcycles:
  
  For motorcycles that are ridden exclusively on the track, we recommend either a top-quality organic pad, or a sintered pad that incorporates some method of reducing interface temperatures. Under the constant, extreme brake loads that characterize track riding, heat-related brake fade and component distortion are common problems. If you're currently experiencing these problems with sintered pads, organic pads are probably the way you want to go. The same goes for iron rotors. Otherwise, the choice between the two pretty much boils down to your personal preference regarding stopping power, initial bite, and feel.
  
  As stated above - in the most general terms - organics are known for progressive feedback, allowing for precise and controlled trail braking. And sintered pads are known for sheer stopping power, coupled with strong initial bite. But the latest offerings from the racing pad industry do a great job of combining the best attributes of each. In the end, you pretty much just have to try a few brands and pick what works for you.
  
  The heat-dependent nature characteristic of many organic pads - the same nature that makes them a questionable choice on the street - is essentially a non-issue on the track. By the second or third turn on your warm-up lap, organic pads will be well up to operating temp. Break-in requirements for organic pads, however, must be followed to assure optimum performance. But once again, this shouldn't be an issue on a track bike.

• Street or Street & Track Motorcycles:

  For riders that spend most of their time on the street, with or without a few track days thrown into the mix, we generally recommend one of our more progressive sintered pad offerings. The brake loads and operating temperatures seen on street bikes are wide and varied, as are the environmental conditions in which they are used. Sintered pads tend to offer more consistent, predictable performance across these extremes, minimizing any potential surprises a rider may experience when the time comes to pull that brake lever. Sintered pads bed-in quickly and easily. And, as almost all production motorcycles come off the showroom floor with stainless steel rotors, rotor compatibility with sintered pads is rarely an issue. In fact, most OEM pads are sintered-metal.
  
  There are, however, a couple of caveats to these recommendations. While sintered pads usually offer improved performance over organics in the rain and snow, sometimes this can serve as a double-edged sword. Sometimes more braking power in conditions of limited traction is a bad thing. So if anticipate riding in the rain, carefully consider your options, your skill level, and what design would work best for you.
  
  Also, if stunting is your thing (or if you're just REALLY hard on the front brakes!), the progressive nature and feel of organic pads is pretty hard to beat when rolling out long endoes.

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