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Street tire static and kinetic friction coefficients?

  1. Jul 18, 2011 #1
    Anybody know where I can find data on normal street-tire friction coefficients on dry asphalt? I'd like both the static, and the kinetic coefficients. If not, can somebody give me a range of reasonable values?

    While I'm at it... What about racing slicks on asphalt?

    I found one source that said the static friction coefficient of a tire on concrete is about 1. But, it didn't say what kind of tire, didn't give me the kinetic coefficient, it's on concrete, and it seems too high.
  2. jcsd
  3. Jul 18, 2011 #2


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    You may calculate static coeff from breaking distance of cars using ABS. For most family cars breaking distance on dry asphalt from 100 km/h is 45-50 meters, thus (static) friction coefficient is 0.8-0.9.
    Porsche 911 Carrera Turbo on rally tyres on standard German asfalt pavement claims breaking distance of 34.5m => f.coeff=1.1

    Regarding kinetic coeff: police forensics use coeff=0.7 for dry and 0.55 for wet asphalt to compute speed from skid marks during collision investigation.
    Last edited: Jul 18, 2011
  4. Jul 19, 2011 #3

    jack action

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    http://hpwizard.com/tire-friction-coefficient.html" [Broken]

    Last edited by a moderator: May 5, 2017
  5. Jul 19, 2011 #4
    Oh, cool. Before I started this thread, I got search results from that site, but the site was down at the time. I didn't know what was on that site. Thanks.
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