| 3/32" | 2.38 mm | Chain/chainring width for most derailer-equipped bikes |
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| 1/8" | 3.175 mm | Bearing balls: freewheels, some headsets, some pedals
Chain/chainring width for most one-speed bikes (frequently rounded to 3 mm) |
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| 5/32" | 3.970 mm | Bearing balls: many headsets, many pedals |
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| 3/16" | 4.763 mm | Bearing balls: most front hubs (10 x 2) many headsets |
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| 7/32" | 5.556 mm | Bearing balls: high end Campagnolo front hubs (9 x 2) |
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| 1/4" | 6.35 mm | Bearing balls: almost all rear hubs (9 x 2)
Most bottom brackets (11 x 2) |
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| 5/16" | 7.937 mm | Bearing balls: bottom brackets for one-piece-cranks.
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| 13/16" | 21.15 mm | BMX
& OPC Stems, seatposts |
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| 7/8" | 22.2 mm | Upright handlebars (grip section), 1" stem quills, BMX Seatposts |
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| 15/16" | 23.8 mm | Drop handlebars (grip secction) |
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| 1" | 25.4 mm | ISO handlebar clamp size, standard top tubes. |
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| 1.024" | 26.0 mm | Italian handlebar clamp size, many higher-end road bars. |
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| 1.039" | 26.4 mm | Old Cinelli handlebar clamp size |
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| 1 1/16" | 27.0 mm | |
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| 1 1/8" | 28.6 mm | Standard steel seat tubes, down tubes, O.S. top tubes |
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| 1 1/4" | 31.8 mm | O.S. seat tubes, O.S. handlebar clamp size, others |
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| 1 3/8" | 34.9 mm | O.S. seat tubes, others |
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| 19" | 48.3 cm | Frame sizes listed in inches are most often "center to top." |
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| 20" | 50.8 cm | |
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| 21" | 53.3 cm | |
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| 22" | 55.9 cm | |
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| 23" | 58.4 cm | |
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| 24" | 61 cm | |
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| 25" | 63.5 cm | |
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