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I thought vented brake rotor disc cooling effect would be more equally spread
Sharing..........
Since my rear brake pads, rotor disc, caliper piston seal and dust boot and parking brake pads.........all are virgin new, yesterday was my only longest test drive so far, after the job completion.
Not too far a distance , but decent. Nope, I can't do proper brake pad bedding, not even on Sunday afternoon, Jakarta sucks for traffic.
I was monitoring brake pad "touch", on dyno mode its been good. But not road tested yet.
Since dyno mode has no wind cooling down the rotor, real driving has wind cooling down the rotor, its nice to see how vented disc helps cooling.
Reading is in Celsius
REAR RIGHT side only ( easier to photo ). 8:18PM. All are 7th Dec Sunday 2025.
I did not expect to see the structural rib of the venting system visible on thermal... now I can see.
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Rear : 8:50PM
When its already cooled down some time later. WHITE/BRIGHT = HOTTER. , DARKER = COOLER
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The front. When already cooler. 8:52PM
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REAR, RIGHT. Monday 8th Dec 2025.
To see permanent marker gone aka friction surface of brake pad to rotor disc
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REAR, LEFT
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Duration of logging chart is 50.90 minutes at 5hz.
Brake Caliper Body temperatures
Lame traffic, as usual
Brake Booster Use. Zero is perfect vacuum or -14.7 PSI equivalent.
Spikes up is when I press the brake and the vacuum reduced. Absolute pressure sensor in use, thus at ambient pressure at sea level it will read +14.7PSI and at "perfect" vacuum, it will read zero PSI.
this is a interesting view of your front disc internal structure.
Infrared imagery showing temps
The working disc really has multiple temperatures areas.
What does that show about the cross-drilling effectiveness ?
Every time I read on cross drilling, it is not for cooling per se. The best cooling is the vented disc design.
It is for venting off the gas which some types of brake pad will produce, so that the brake pad can contact rotor disc better.
Asbestos oohhhh, that is old stuff
When I think of vented rotors, I think of slotted, and/or drilled rotors.
The one picture that I saw that is different from how I think about vented, is curved valleys sandwiched inside 2 smooth exterior rotors.
Is that about right?
Great idea for a thread, and the IR pictures tell a story of at least a thousand words.
S. Prihadi for MBWorld Hall of Fame!
Mine is light weight and has tripod thread on its bottom, but it is not the most sensitive for today's standard for the price. It is only at 70 mK thermal sensitivity.
Also USA controlled thermal, hence only 9hz and that is a crappy for video. Now US$300 cheaper than when I bought it 7 years ago in 2018. https://www.thermal.com/seekshot-series.html https://www.thermal.com/uploads/1/0/...ecsheet-v3.pdf
Actual video footage I took of the rear brake while on dyno mode. No sound. Recording frame rate is 17 FPS, but refresh rate is still the 9hz.
I guess doubled up for video but the data is worth only 9 hz and not 17 hz.
You are better off buying this 25hz unit below , albeit less thermal sensor resolution than mine which is 320 x 240 = 76,800 pixels
Thermas Master THOR 2 , True Resolution of imager is only : 256 x 192 pixels = 49,152 pixels. Becareful of their line doubler bull-shiet claiming double resolution.
40 mK thermal sensitivity. The lower the number the better the unit is .
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Thermal imager sensitivity, also called Noise Equivalent Temperature Difference (NETD), is the smallest temperature difference a camera can detect, measured in milliKelvins (mK); a lower mK value means higher sensitivity, allowing the imager to see finer temperature details in low-contrast scenes like fog or smoke, crucial for better image quality, detection range, and reliability in challenging conditions. Key Aspects of Sensitivity
NETD (Noise Equivalent Temperature Difference): This is the standard metric, representing the electronic noise level of the sensor translated into a temperature difference.
Units: Measured in milliKelvins (mK); 1 mK is one-thousandth of a Kelvin or Celsius degree.
Low is Better: A lower NETD (e.g., 20mK vs. 50mK) indicates a more sensitive detector, capable of differentiating between very subtle heat variations.
I am still waiting for thermal master to up the sensor resolution and if NETD can be 35 mK, it will be awesome.
FLIR is too expensive and low refresh rate due to restriction.
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BUT there is one thing FLIR does well, each pixel of the FLIR has its own meta-data for review at end of working day.
I have an old FLIR, this one : a 100 mK sensitivity. only 80 x 80 pixels
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