Road Bike Tire Sizes Explained

When it comes to choosing width there are two major factors at play.

Road bike tire sizes explained.

The second number refers to the tire diameter in millimeters in most cases this ranges from 23mm to 28mm for road tires but can be upwards of 35mm for cyclocross and recreational use tires. When shopping for road tires you ll look for 700c x your preferred width 23mm being the slimmest option and going up to 36mm. Road tires generally come in the size 700c which roughly equals 700 millimeters. These sizes are almost never found on production bikes but if you re over 6 6 and looking for a bike that fits custom built might be the only way to go.

The letter at the end of a tire size is a throwback to an old french system when the letters a b and c designated different inner tire diameters it does not stand for cm. Size used on some high performance road and triathlon bikes especially those designed for smaller riders. 23c 25c and 28c their width in mm. Some older road bikes still have the 27 inch size.

The first number refers to the rim diameter in millimeters in most cases this figure is 700c. Iso etrto mm english size inch french size mm 35 584. A standard road tire is 700c x 23mm indicating a tire diameter of approximately 700mm and a width of 23mm. Most road bikes have a 700mm outer diameter with widths starting at 23mm.

Some bikes especially triathlon bikes are available with wheel diameters of 650 or 650c. Because of the high pressure and desired low rolling resistance road tires come in narrow widths. While you can find a variety of bikes with wheel sizes ranging from 16 to 27 5 inches the most common sizes include 26 inches 27 5 inches 29 inches and 700c. 27 5 584 mm 650b tires.

Road bike tires generally come in three widths. 27 5 650 6fattie or even just plus tires. All inner tubes will come with a recommended range for tyre width for example 700 20 25 for traditional road tyres 700 25 32 for wider road tyres. Most road tire widths are less than 30mm but you can also find tires as wide as 45mm on bikes intended for gravel roads.

26 1 3 8 1 1 2. Used on mountain bikes these tires also go by the names. Tubes can range anywhere from 1 to 3 inches or 19 to 45 millimeters depending on the type of wheels you have. 32 iso 686 mm and 36 iso 787 mm while extremely uncommon custom built frames for very tall riders often use 32 or 36 wheels.