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Old 09-21-16, 11:19 PM
  #1053  
Koogar
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Originally Posted by brawlo
....I think you'll find the issue will be twofold with max pressure. One factor is the quality of the lip/hook on the rim, and the second will be the quality of the bead on your tyre. If you look at the construction of modern aluminium rims, then they are a double wall design and I would say, very unlikely to spread under any normal (even high up to 160+psi) pressure. Also consider (especially with carbon rims) that what causes rims and tyres to fail is heat buildup. This isn't really a factor on track wheels.
I largely agree with you, brawlo. To be explicit about the heat buildup issue you mention: on the track we don't have to deal with rim braking-induced heating that increases temperature and pressure, which could contribute to several different failure modes. At the same time, I've noticed that wheel manufacturers don't necessarily quote a higher pressure for disc brake wheels. This could be purely liability-driven. And there should be a large safety factor built in to account for inaccurate pressure gauges, weakened rims, non-compliance, etc. But without the data that underpin these limits and being of the understanding that sky high pressures don't tend to provide much benefit in terms of rolling resistance, I personally don't feel compelled to push tire pressures on the track. On a relative basis, the rationales to do so are even weaker if the rider is relatively light or the surface less than perfect. I'm totally open to the possibility that I'm being overly conservative, I just don't feel like I have sufficient data to conclude that at this point.
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