Kolari Vision, a company known for various camera modification services, introduced a $400 heatsink improvement program for the Canon R5. After they muck in the intestines of your R5, it will come back with a new piece of copper hardware that draws heat into more parts of the camera, reducing the load over the main processor.
This translates to roughly doubling the time you can film in 8K at room temperature, and then roughly tripling what you can film after a five minute cool-down period. At 60 degrees, it doesn’t appear to overheat much at all.
The modification process typically takes two weeks, and Kolari claims on its website does not cause any diminishment of the weather sealing of the camera.
Importantly for many of the R5 owners who pre-purchased the body for the July 9, 2020 launch, the Canon warranty ends precisely on the day Kolari could get the camera back to you were you to purchase the service today and ship your camera to New Jersey overnight.
The firm put up notably terrible demonstration video that we suppose suffices as proof of performance.