Size used on some high performance road and triathlon bikes especially those designed for smaller riders.
Road bike tube sizes explained.
Road tubes come in different widths but not as broad a range as mountain bikes.
Thus you need to be sure any new bike tube has sizing that has a width range that aligns with the sizing on your bike tires.
A typical road tube box may say 700 18 23c or 700 25 32c.
Tubes because they can stretch will list a range of widths.
Bike tube sizing essentially mirrors bike tire sizing with one exception.
How to get the right bike tube and valve size.
As the width decreases there is less rolling resistance or friction and therefore is faster.
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 bike tires generally come in three widths.
A narrower inner tube will balloon out to.
There are a myriad of wheel sizes for road mtb touring and children s bikes.
700 or 26 but the tube s width will vary depending on the amount you inflate them like a kid s balloon.
The steerer tube of the fork is threaded and a threaded race is screwed into the top of the fork to snug up against the top bearing.
27 5 x 1 9 2 3 for example.
Mtb wheels in particular can be further categorised by 26 inches 27 5 inches and 29 inches.
The diameter needs to be the same e g.
This is the reason why you see inner tubes listed with one number for the diameter and a range for the width e g.
Common inner tube ranges for 26 inch 27 5 inch and 29 inch tire diameters 1 0 to 1 15 inches 1 25 to 2 0 inches 2 0 to 2 35 inches 2 4 to 3 0 inches.
The standard sizes are 1 inch 1 1 8 inch 1 25 inch and 1.
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.
Check your tire sidewall for width and choose the right tube accordingly shown as 700 x 23c etc.
You can also get 26 inch mtb tubes.
Sizing width may vary from 18c through to 28c meaning 18mm through to 28mm.
A standard road tire is 700c x 23mm indicating a tire diameter of approximately 700mm and a width of 23mm.
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.