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  1. #1
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    27.5 roll out measurement

    Looking for the roll out measurement for my Bronson, tires are High Roller II 2.4
    I tried the measurement and came up with 2140mm. Am I close?

  2. #2
    NedwannaB
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    Quote Originally Posted by jgutz71 View Post
    Looking for the roll out measurement for my Bronson, tires are High Roller II 2.4
    I tried the measurement and came up with 2140mm. Am I close?
    Right. Wait! Wha? You did it but want someone else to check it? What exactly are you trying to get at??
    Wait,who did he tell you that?....

  3. #3
    Doesntplaywellwithmorons!
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    Pi times the diameter will give the number also...
    I don't post to generate business for myself or make like I'm better than sliced bread

  4. #4
    www.derbyrims.com
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    Doubt if the number is correct, 26.85 inch diameter? I've seen the 650b Highrollers on a Bronson, it is no shorter than my relatively average diameter 650b Neo-Moto 2.3 which is 27.55 inches diameter and about 2195mm rollout circumference.

    Try 2 full wheel cycles, measure and divide by 2. Mark a side knob, start the rollout with that mark at the floor, plum to the axle.

  5. #5
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    OP, are you weighting the wheel? If weight is applied during the rollout, it will measure smaller than an unweighted measurement. It will be hard to compare against rollouts derived from direct diameter measurements, which are normally unweighted.

  6. #6
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    @ derby: I will try the two complete wheel rotation and see what I get, thanks for the info...
    @ lixxfe: no I didn't weight the wheel, I'll give that a try when I do the two complete wheel rotation...
    @ JMac47: have a nice day...NOT

  7. #7
    NedwannaB
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    I'll try a re-wording: What are you trying to achieve/compare/accomplish by getting this number? Other peoples tire measurements? Or just how to figure out the way to do it?

    Thus the "what are you getting at?".
    Wait,who did he tell you that?....

  8. #8
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    My apologies JMac47 I misunderstood you...I was simply trying to verify my math by comparing what others have measured.

  9. #9
    NedwannaB
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    Quote Originally Posted by jgutz71 View Post
    My apologies JMac47 I misunderstood you...I was simply trying to verify my math by comparing what others have measured.
    Cool. No worries. I see a lot of the micro-measuring of tyre vs tyre, tyres vs rim widths, bb heights, head angles, stem lengths, flat bar vs risers etc etc etc.

    Similar to all the gear inch topics with single speeds. Some times just a change in a specific tyre will make the same difference as a tooth on the cog/ring.
    Wait,who did he tell you that?....

  10. #10
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    Quote Originally Posted by jgutz71 View Post
    @ lixxfe: no I didn't weight the wheel, I'll give that a try when I do the two complete wheel rotation...
    Weighting the tire will give you a *smaller* measurement. I was trying to offer an explanation for Derby's comment.

    Another factor is tire pressure.

  11. #11
    NedwannaB
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    Like I said, lots of "micro-measuring" going on. Pick a tyre and ride your bikes peoples!!
    Wait,who did he tell you that?....

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