frame dims

RJHazell

i have a bare frame.

how do i measure it up so that i can purchase the correct size BB and cranks?
how do i measure so that i can purchase the correct seat post and clamp?

rjh

cooldad

A tape measure?

supersonic

Vernier caliper or very precise steel ruler for the latter.

For the former, measure the width of the bottom bracket shell to start. If 68 or 73mm and threaded then the majority of external bottom bracket (Shimano HT2, GXP) chainsets will fit as come with spacers and the bottom bracket already.

ride_whenever

Go to your local friendly bike shop and ask nicely when they're not too busy.

cooldad

For the clamp and front mech the easiest way is to measure the circumference of the seat tube with a tape measure and divide by 3.14, which will give you the diameter of the clamps.

There are 3 standard sizes:

9cm seat tube circumference = 28.6mm clamp
10cm seat tube circumference = 31.8mm clamp
11cm seat tube circumference = 34.9mm clamp

RJHazell

Wrong end of the stick guys.

Vernier: Check.

Is the seat post size measured by the ID of the frames' seat tube?
Is the stem/handlebar size measured by the ID of the Stem ...hole (?) / OD of the handlebar?

nicklouse

RJHazell wrote:

Wrong end of the stick guys.

Vernier: Check.

Is the seat post size measured by the ID of the frames' seat tube?
Is the stem/handlebar size measured by the ID of the Stem ...hole (?) / OD of the handlebar?

seat post internal but better done with a seatpost sizing tool as they vary by 0.1mm

see the headsets standards on Parktools as it is not as simple as there are more than one headset standard.

and eazy way is to mention the make model and year.