British and italian standard for seat tube diameter was 1 1 8 28 6 mm.
Bike seat tube sizes.
First bicycle frames were made mostly from steel with steel tubes of a standard outer diameter.
One size that fits the average population of adults and other bikes that come in different sizes just like clothes.
Older french bicycles used 28 mm tubing.
Schwinn bikes that come in one size if you are an average sized adult male or female you will be able to fit 90 of schwinn s bicycles that come in a single size.
The seatpost must be inserted at least a certain length.
Most steel bicycle frames have tubing of standard outside diameter.
If all three have a 15 frame there will be a height difference between them due to their wheel size.
The seat tube contains the seatpost of the bike which connects to the saddle.
This is marked with a minimum insertion mark.
99 13 99 13.
The top tube length is measured along the top tube starting at the center of the seat tube and ending at the center of the head tube.
Some bikes like the trek madone have a.
While there are now fewer frame sizes to choose from for many mass produced bikes deciding on a frame size remains a convoluted process.
Bike frames are measured from the middle of their bottom bracket to the end of their seat tube.
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.
While not all bicycle frames have a size label it ll save you some work if yours does.
Old us bicycles mostly bmx and older bikes that used one piece cranks was 1 25 4 mm.
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.
We usually give four sizes for the complete bicycles and three sizes for the frames.
Frames made to british or italian standards will typically have 1 1 8 28 6 mm seat tubes older french bicycles used 28 mm.
You can find them with 26 wheels 27 5 wheels or 29 wheels.
Schwinn bikes come in two variations.
The seat tube is the long tube that the bike seat post sticks into.
On some bikes this is achieved using a quick release lever.
Again it s trickier than it sounds.
Seat tube length is the straight line distance between the centre of the bottom bracket and the top of the seat tube.
Upanbike aluminum alloy bike seat post length 350mm30 8mm black for mountain bike fixed gear bike seatpost four sizes for you to choose by upanbike 12 99 12.
If the size isn t given.
The saddle height is adjustable by changing how far the seatpost is inserted into the seat tube.
