Bicycle Wheel Sizes for Adult Bikes

There are a couple of wheel/tires sizes that are standard on American Bicycles.  Bicycle tire sizes are normally measured on the outside of the tire and this is called the nominal tire size.  For example a 26 x 2.0 tire will fit on a 26 x 1.75 or 26 x 1.5 wheel.  The approximate outside diameter with the tire installed is 26 inches. 

 What is the difference between 26 x1.75 and 26 x 1 3/4?
The 1 3/4 size is actually a different bead size so the tires will not interchange.  The 26 x1 3/4 is an old Schwinn size that has not been made since the 60’s but the tires are still available to fit these rims.

Is 27″ the same as 700c?
No the 27 x 1 1/4 tire will not fit a 700c rim.  The bead of the tire is about 1/2″ too big.  Tubes will normally work on either 700c or 27″ tires just fine.

Is 29″ the same as 700c?
Yes, the bead size of a 29″ mountain bike wheel is the same size as the bead size of a 700c rim.  Normally the mountain rims are a little bit wider to allow the 29″ tire to fit a little better.

Old 3 speed bicycle sizes
The old 26 x 1 3/8 tire size is not the same as the 26 x 1.75 or the 26 x 1 3/4.  There is also another 26 x 1 3/8 tire size that was made by Schwinn until the late 70s that was called 26 x 1 3/8 or 26 x 1 1/4.  The bead of this rim is just large enough that it seems you will be able to get the regular 26 x 1 3/8 tire on.  You will ruin the tire if you do get it on and it is nearly impossible to get back off.

Rick Kern Bicycle Hangar Missoula, Mt

Leave a Reply

Your email address will not be published. Required fields are marked *