Originally Posted by
jpshaw
I know, a dumb question but I'm not getting any smarter until I ask. My cruiser's tire says 26 x 2.125. Replacement tubes are 26 x 1.75 - 2.25 and when I checked on new tires they said 26 x 1.75 - 2.25. So does the rim alone determine if it's going to be 1.75 or 2.125?
a couple of my favorite references for figuring out if my rim is wide enough for the tire I want to use:
Tire Sizing Systems
https://www.schwalbetires.com/tech_info/size_markings
Page 10 of this PDF for rim width to tire diameter:
https://www.schwalbe.com/en/cataloge...fo-2015_GB.pdf
-- is your question how fat the tire is? The diameter of "fatness"? Or how BIG the WHEEL is?
As mentioned in the first response, there is the WIDTH of the tire, FATNESS.
Then there's the SIZE of the wheel, how tall the wheel is. The tire you can fit on the rim is determined by the Bead Seat Diameter, and how fat of a tire you can fit on your bike depends on bike clearances. And of course the FATNESS affects how TALL the wheel is too.
What's really confusing is you can get an old "27 inch" road bike wheel from the 70s and 80s. The RIM is bigger than a 700C wheel you can get then and now.
BUT when you buy a "29er", the BSD is the SAME as the 700C wheel, but it's called a bigger size than the old 27in wheel! Which actually has a "taller" rim..... ugh.
And make sure you know the difference between your 26in MTB wheel and your 26in cruiser wheel from the '60s!
Any way, two cents worth. Cheers!