Road Bike Frame Tube Diameter

Read on to find out how to size up your road bike or mountain bike frame.

Road bike frame tube diameter.

If you want to know the sums then to find your road bike frame size take your inseam length in centimeters and multiply it by 0 70. Frames made to british or italian standards will typically have 1 1 8 28 6 mm seat tubes older french bicycles used 28 mm. Let s say your wheels have a 26 inch diameter and a 1 3 inch width. By the late 70 s reynolds advertised variations on the basic set of tubes with options for touring and larger frames.

For a hybrid bike take your inseam and multiply it by 0 69. Most steel bicycle frames have tubing of standard outside diameter. If you look near the bottom of this tube about 3 inches 7 6 cm up from the chain sprocket you ll see a glued on label that states the bike s frame size. Heat treated reynolds 753 appeared in 1978 which was offered in wall thicknesses down to a 7 5 7 top tube and 8 5 8 down tube on road bikes.

Getting the size right is essential. The seat tube is the long tube that the bike seat post sticks into. Tubes are basically suspended beams. If you find a tube that s 26 x 1 1 1 5 for instance that will fit your tires.

If the size isn t given. Ridley s size s frames have a top tube around 54cm which is equivalent to many brands size medium frames. Other tube manufacturers soon followed with their own heat treated offerings. This diagram shows the various tubes that make up a road bike frame immediate media co manufacturers make frames in various sizes to suit the variety of riders.

When a road bike fits properly it s more efficient easier to handle and better at transferring your power to the road. For mountain bikes take the same measurement and multiply 0 6 you will then need to change the centimeters into inches. Old american style commonly used on bmx bicycles and other bicycles that use one piece cranks uses a 1 seat tube standard outside diameter accommodates standard lugs and clamp on parts such as front. There s much more to understanding road bike frame sizing than effective top tube length stack and reach and choosing the right size is key to proper fit and handling.

As long as you buy tubes made for a 26 inch diameter wheel you can buy any range of tube width that covers 1 3. Tube size is a whole another matter as described below. From the calculations by peterson and londry most of the forces are bending therefore the tubes when in a bicycle frame act more or less as a suspended beam. While not all bicycle frames have a size label it ll save you some work if yours does.

Deflection at one. The deflection can be summarized by the equations below.