HLS2K6, this is the issue that puts us and everybody else in the legal position of saying 'use at your own risk'.
Our platinum rim tape is made from a higher strength grade of base film as most of the other tubeless tapes on the market, so it has a similar melt point (actually 10 deg F higher..but nearly identical). The Platinum Tape film is stronger than other tapes, but we use that property to make it slightly thinner, which gives it much better conformability to the rim bed at an equivalent strength to something like the popular yellow tape. The Platinum tape does have a higher strength, full-synthetic adhesive, that is more heat tolerant than the natural rubber adhesive used elsewhere, but that can only ensure reduced movement of the tape and once the tape film begins to melt, the adhesive can't do much anyway.
The problem with this from a system perspective is that we can't control the system in a way that allows us to safely make blanket statements. This is why nobody making tubeless tape really says much of anything about rim brakes. Similar to latex tubes, what works for a 160lb person on 500 gram rims will be very different for somebody who weighs 220lbs on 300 gram rims, and that's before we even begin to talk about what you are descending and for how long..
Our testing has shown the tape to have similar heat tolerance to latex inner tubes in practice, that is to say that if a latex tube bursts due to heat after 2 minutes of 300 Watt Braking input, then our rim tape will fail similarly. Technically the tape has about a 30 degree advantage over a latex tube, but as the tape is directly against the rim surface, it sees more heat, whereas a latex tube will be slightly insulated by whatever rim tape you are using.
As with any tape, using more will add safety margin, we are working on some technical data now, but using 3 wraps instead of 2 puts you at the weight of 2 wraps of yellow tape, but significantly stronger AND higher temperature resistance due to the insulating effect of the additional layers of adhesive, 4 wraps would be even better for the same reason. Of course, just like latex tubes, the real key is brake modulation and ensuring you have the right pads for your rims.
Hope that helps
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