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Incorrectly marked tire width?

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Incorrectly marked tire width?

Old 10-24-20, 11:39 PM
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cubewheels
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Incorrectly marked tire width?

I'm currently using no-brand tires which came with my road bike purchase.

The tires are marked 700 x 35c but when I measured the width of the correctly inflated tires, it's only 28mm across. The outside rim width is 20mm.

Does this mean the tires are actually 700 x 28c, mislabelled as 35c??
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Old 10-25-20, 06:18 AM
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The actual tire width, once mounted on a rim, is dependent on rim width and tire pressure. In addition, the stated tire width is typically just a nominal value to compare it to other tires made by the same manufacturer. For example, I run 700c x 28 on my road bike, but at the pressure I run (80 psi rear, 60 psi front) they measure out at 26.5 mm. With that said, the 7 mm difference between the specified and actual width of the tires you have does seem a bit excessive.

Last edited by Cyclefiend; 10-25-20 at 06:21 AM.
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Old 10-25-20, 06:59 AM
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Wow... that's a pretty big difference. It's been my experience that the labelled tire width, like on a Continental GP5000, is usually pretty close to the actual measured width. Given that your rim width is pretty standard, I don't see how a 35mm tire could be reduced to only 28mm in width.

Does your new bike have rim, disc, or cantilever brakes? If it has rim brakes, there's no way the tires are 35mm wide as no rim brake I'm aware of can handle a tire larger than 28mm.
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Old 10-25-20, 08:03 AM
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I think the tire is probably bottom end, very cheap ones. The maximum pressure on the thing is only 45 psi. I only inflate it to 45 psi.

Bike has disc brakes.

Yeah, the tires ending up with an actual width of 28mm seems uncanny. Both tires front and back are the same, marked 35c but both measured 28mm.
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Old 10-25-20, 04:03 PM
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It may be the narrow rim width and if the rim is hooked or not. 20mm outside width may be something like 14mm inside. A wider rim would stretch it out more.
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Old 10-25-20, 04:39 PM
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That's way off. I've never seen a tire that measures a whole lot less than its stated width, no matter what tire or wheel it's on! Are you sure it says 35? 25 would make more sense.
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