In our rig testing, a standard two-stage bed-in (heating to 150°C, cooling, then heating to 225°C and cooling again) didn't stop several pads losing power later, at around 250°C, before recovering at around 350°C. During the testing, Lee Hine of Gorilla Brakes also saw that heating the pads further went along with a better-developed transfer layer on the rotor and more braking power. Put together, this suggests a typical bed-in can leave some pads only partly bedded in and not yet ready for hard use.
What we found
The report documents two things:
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The bed-in didn't prevent later dips. Every pad was bedded in with heating cycles to 150°C and 225°C, with cooling in between. Many pads still dropped off in power at around 250°C and recovered at around 350°C. The report concludes that the bed-in "needed to continue to a higher temperature than 225°C".
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The dips are consistent with green fade. That's the temporary power loss new pads can show the first time they get properly hot. A single heating curve can't prove the cause, but the pattern fits.
Lee Hine's first-hand observation: taking pads beyond the initial bed-in to higher temperatures went along with a better-developed transfer layer on the rotor and more braking power.
The report doesn't measure that observation. We didn't re-test pads at matching temperatures after they'd cooled, so we can't say yet whether the extra power lasts. A before-and-after comparison at the same temperatures would help answer that.
Why bedding in is more than one job
Bedding in does three jobs at once:
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Building the working surface. The pad face is flattened and imperfections are worn away, so pad and rotor make even contact.
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Laying down a transfer layer. A layer of pad material builds up on the rotor surface. That layer is what the pad works against.
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Heat conditioning resin-bound pads. Most pads use a resin binder. The first time they get hot enough, the resin finishes curing and can give off gas, which can push the pad slightly away from the rotor. That's the classic explanation for green fade, and it "usually only happens once", as the report puts it. Sintered pads are made differently, from metal particles fused together, so this resin explanation doesn't apply to them in the same way.
All three jobs carry on as temperatures climb. That's why power can rise, dip and recover during a pad's early life, and why we don't put green fade down to resin curing alone.
The practical point is that good initial bite, or completing a set number of stops, doesn't by itself show a pad is stable across its whole operating range.
Our concern about common bed-in routines
Based on this testing and our experience, we're concerned that many common manufacturer bed-in routines may not generate enough heat to finish bedding in every pad and rotor combination. That's a concern, not a proven finding: our testing didn't compare different manufacturers' procedures.
The temperatures in this article are what we observed on our rig with these combinations. They aren't universal thresholds, and they aren't targets to aim for on the trail.
How we tested
Gorilla Brakes and HINE-R Engineering ran the testing together on 8 September 2026 at "The Lab" in Darwen, North West England. Adam Read of HINE-R Engineering, who has worked in the cycling industry since 2001, built the rig and wrote the report. Lee Hine, who has been working with and selling bike brakes since 2012, supplied the pads and contributed throughout.
Read the full lab report
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Brake: Shimano M9100 lever, HINE-R Wilfred caliper and HINE-R hose, Shimano LV mineral oil, and a Shimano RT86 rotor in 203mm.
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Lever force: a fixed 22.5N, from a 2.3kg weight hung from the lever blade.
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Speed: a constant-speed lathe at 200rpm.
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Rotor temperature: a K-type thermocouple on a skid running against the rotor.
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Caliper temperature: a surface probe on the caliper body. This is the caliper's surface temperature, not the temperature of the brake fluid inside it.
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Cooling: no fan during test runs.
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Braking power: worked out from how much extra electricity the lathe drew while braking, compared with its unloaded reading. These are comparative rig readings, not stopping distances.
What the charts show
Braking power (W) against rotor temperature (°C) for each pad, from the Gorilla Brakes and HINE-R rig testing on 8 September 2026. These are comparative rig readings, and some data points were left out to smooth the curves. All values below are read approximately from the plot.
- Several pads, including Enduro Pro Resin, Factory Racing Stealth and Green, and UberBike Heat Escape, dip in the region the report describes (around 250°C) and recover towards 350°C.
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Enduro Pro Ultimate on the Shimano RT86 ramps up with heat rather than fading over most of its range, reaching roughly 1,350 W at around 375–380°C.
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Enduro Pro Ultimate on the TRP R1 is a separate combination. It gave much more power from cold, and the report notes the rotor "appeared to make as much if not more difference to braking power than the pad type".
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Gorilla Sintered stays fairly flat, at roughly 960–1,020 W, but its curve ends at around 270°C, so it shows nothing beyond that.
Caliper surface temperature (°C) against rotor temperature (°C), from the same testing. Comparative rig readings, smoothed in the same way. Values read approximately from the plot.
- In this setup, pads with more metal content passed heat to the caliper faster. The sintered pads reached 120°C at the caliper at nearly half the rotor temperature of the semi-metallic and ceramic pads, and their test had to be stopped early.
- Trickstuff Power kept the most heat out of the caliper.
- These results are specific to this rig. How long the brake is applied, which rotor is fitted and how much cooling airflow there is all change how much heat reaches the caliper.
A destructive rig test, not something to copy
At the end of the day, Enduro Pro Ultimate pads on a TRP R1 rotor were run until something failed. The rotor reached around 650°C and glowed orange. The report notes "no brake fade even at this temperature", until the hose liner and then the caliper seals failed. This was a deliberate destructive test on the rig. Don't try to recreate it.
On the trail
Lab temperatures are observations, not targets. Don't try to overheat your brakes, provoke fade or ride through a loss of braking. Follow our bedding-in guide, ride carefully on new pads, and treat their first long, hard descent with respect.
Limitations
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One main test per pad. Without repeat runs we can't show how consistent each curve is.
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Incomplete bedding, especially the sintered pads. The report says incomplete bedding "significantly affects the validity of the results", and the sintered pads still weren't fully bedded in after the main test. Some of the dips may reflect pads still bedding in, rather than how they'd perform once settled.
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Dry, clean conditions with no cooling airflow. Real riding is often wet, dirty and cooled by moving air, which changes temperatures and friction.
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Timing inconsistencies and changes in braking intervals. The lathe's power meter averages the last 3 seconds, so some applications ran to 3.5–4 seconds. The switch from short to long braking intervals partway through was hard to keep consistent. Both mainly affect the caliper vs rotor temperature results.
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Some data points omitted to smooth the plots. The curves are cleaner than the raw readings, so small wiggles shouldn't be over-read.
The report sets out a plan for future testing with a longer bed-in, including a stage to 350°C, and two main tests per pad.
Choosing pads
If you ride long descents, Enduro Pro Ultimate ramped up with heat in this testing. It's available for Shimano 4-piston, Shimano 2-piston, SRAM Code / DB8 / Motive and Magura MT5 / MT7 brakes. To weigh up compounds, see our compound comparison. For the right fit, use the Gorilla Brakes pad finder.
FAQ
What is green fade?
A temporary drop in braking power the first time new pads get properly hot. In resin-bound pads it's linked to the resin finishing curing and giving off gas.
Does a normal bed-in stop it?
Not always. Our bed-in went to 225°C, and many pads still dipped at around 250°C afterwards.
Should I heat my brakes to 350°C?
No. Those are rig observations, not targets. Follow the bedding-in guide and ride carefully on new pads.
Do sintered pads get green fade?
The resin explanation doesn't apply to them in the same way. In our testing they took longer to bed in, and their power curve ends at around 270°C.
Is caliper temperature the same as fluid temperature?
No. We measured the caliper's outer surface, not the fluid inside it.
More testing to come
We're still testing, and we have plenty more data to add once we've got it all written up. Check back here and on our lab report page for updates.