Bike Head Tube Sizes

Out of the three fork trail arguably tells us the most about how a bicycle will steer.

Bike head tube sizes.

The headtube angle is the angle at which the head tube is to the ground. Head tube angle fork rake or offset fork trail. But let s start with the head tube angle. This can seem confusing because the head cups do not measure the named standard.

This size was also used for older british steel drop bars. So a 29 inch mtb tube will have the same diameter as a 700c road wheel while a 27 5 inch tube will be the same diameter as a 650b road wheel. Mainly bmx older mountain bike bars. Traditionally these have been held in pressed cups but modern bikes also see bearings fitted directly into the frame.

Mountain bike tyre sizes are usually stated in inches. Head tubes can use one of several size standards bicycles. Some bikes like the niner air 9 carbon which has a 100mm tall headtube were simply incompatible with rockshox. 7 8 obsolete british size for steel handlebars common on older 3 speeds.

The head tube of a bicycle is sometimes designated by the fork steerer column it accepts. Threaded headset sizes are designated by the outer diameter of the steering column. The various standards are generally not interchangeable. Stem clamp size grip area size application.

This was especially challenging on 29ers where riders demanded shorter head tubes. 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. The threaded standards are 1 inch 1 1 8 inch and 1 1 4 inch headsets. The two bearings at either end of the head tube are what make things work.

This can lead to confusion since head tube inside diameters are dependent on the headset standard. 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. A bike with a steeper head angle has faster steering.