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  1. #1
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    Rim width vs tire width Acceptable minimums

    I have a set of Alex Adventurer rims (700c size) which have a width of 24.2mm. What is the narrowest tire that I could put on this rim? I'm guessing that a 700c x 25 would be cutting it too close, but what about a 700c x 28? Experiences or recommendations about a minimum tire width?

  2. #2
    Low car diet JiveTurkey's Avatar
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    I'm guessing 24.2mm is the outter width, as that is pretty wide. It's the inner width (between the two bead seats) that you should measure.

    Sheldon Brown has a chart for matching rim and tire widths: http://sheldonbrown.com/tire-sizing.html#width

    The chart recommends a 25mm tire be paired with a rim that has about a 13 to 17mm inner width.
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  3. #3
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    A true 28mm tire would be the minimum. . . . . meaning a tire that actually measures at least 28mm wide...not one that just says so on the label. Keep proper pressure levels.

  4. #4
    Senior Member marvelous's Avatar
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    My understanding of things is from reading C. Calvin Jones's book The Big Blue Book of Bike Repair. He states that a tire should be 1.5 to 2 times the width of the rim.
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  5. #5
    aka Phil Jungels Wanderer's Avatar
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    The actual width of those Adventurer rims is 18. Check the label - it will say 622X18.......

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  6. #6
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    As others have posted it is the INTERNAL width that determines what tires will fit correctly. I have gone one size narrower on a tire than recommended and going wider on tires than the ISO/ETRTO recommendation is relatively common, even from bike manufacturers.
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    It is hard to go by the size written on the tire. In the past I used to buy Specialized tires and I'm sure that the 700x25 actually measured 25mm wide, but the Michelin tires I'm using now say 700x20 but they still measure 25mm wide.

  8. #8
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    Quote Originally Posted by bjtesch View Post
    It is hard to go by the size written on the tire. In the past I used to buy Specialized tires and I'm sure that the 700x25 actually measured 25mm wide, but the Michelin tires I'm using now say 700x20 but they still measure 25mm wide.
    Years ago I bought a set of Vittoria folding tires that claimed to be 700 x 25. Mounted width on a normal road rim measured 20.5mm actual width fullly inflated.
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