I am still not convinced it is legally possible to create "DOT legal" bicycle tires at all.
From what I have read
starting here, about tire requirements-
http://edocket.access.gpo.gov/cfr_2009/octqtr/pdf/49cfr571.119.pdf
and extending into the next section, which deals with rim requirements-
http://edocket.access.gpo.gov/cfr_2009/octqtr/pdf/49cfr571.120.pdf
...a DOT-legal tire is only DOT-legal when mounted on a DOT-legal rim, and a DOT-legal rim has to be designed to handle the vehicle's gross weight rating, which is specified in the vehicle's certification label-
S5.1.2
Except in the case of a vehicle which has a speed attainable in 3.2 kilometers
of 80 kilometers per hour or less, the sum of the maximum load ratings of the tires fitted to an axle shall be not less than the gross axle weight rating (GAWR) of the axle system as specified on the vehicle’s certification label required by 49 CFR part 567. ...
Seems to me like any DOT-rated bicycle tire would need to be rated for a DOT-rated rim, that was itself rated for
some classification of motor vehicles, as defined under DOT rules--and bicycles aren't motor vehicles under DOT rules.
I am not a lawyer though.
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I also realize that you guys looking for DOT-legal bicycle tires haven't been told you need DOT-legal rims--but the fact is, you cannot get tires DOT-certified without DOT-rated rims to get them certified on.
Here is the parent index of that page, if you want to poke around yourself-
http://www.access.gpo.gov/nara/cfr/waisidx_09/49cfr571_09.html
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I would think that bicycle tires
could pass the actual tire tests, from what I've read of them in those links. So as far as that part of it goes--I doubt you'd be guaranteed to get any stronger of a bicycle tire if it was DOT-rated or not.
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