Alzerbster

My son has an older bike with a tire size as 26 x 2.10. There are not many tires available in that tire size, so I was wondering if a tire in the 26x1.75 to 2.0 range would fit the rim okay?

Andrew R Stewart 

Yes, the 1.75-2.0" tires should fit the rim. Note the tube's width and that it might also want replacing with a slightly narrower one, or not. Whoever mounts the tires will determine that.

While the 26" size (559 ISO) isn't anywhere as common on new bikes these days there are millions of bikes in use that use it and any decent LBS can special order a pair of tires from one of their distributors. Andy

Alzerbster

Okay thanks Andy, I kind of thought that, but just wanted to make sure before I told my son it was okay to get say a 2.0 or 1.75 tire width.

Bill Kapaun

Likely you could run a tire from 26x1.25" to 26x 2.2" just fine.

Alzerbster

Okay thanks Bill for the info. That certainly increases tire options, being able to get a bit different size tire than 26 x 2.10

Bill Kapaun

On my "grocery getter", I run a 1.25" on front and a 1.6" on the rear with "typical" MTB rims.
My riding is all smooth pavement, so I use slicks.
I'll put 50+ lbs. in my rear baskets. Although I'm about 190 now, I was around 250 a couple years ago.

The tire weight reduction makes the bike MUCH sportier. Acceleration is noticeably quicker and slogging up hills is easier.
You may need a better pump, since your pressures will be in the 70-90 range.

WizardOfBoz

Be careful. This following is from Sheldon Brown (a late expert whose website is legendary). If you have 26 x 2.2, you can use a 26 x 2.2, or x 2.0, or x 1.75. but as Sheldon pointed out, don't expect a 26 x 1-3/4 to fit. The following is from: https://sheldonbrown.com/tire-sizing.html. I think the official size of what you have is ISO 559.

Does Point Seven Five Equal Three Quarters?

Inch-based designations sometimes express the width in a decimal (26 x 1.75) and sometimes as a common fraction (26 x 1 3/4). This is the most common cause of mismatches. Although these size designations are mathematically equal, they refer to different size tires, which are NOT interchangeable. It is dangerous to generalize when talking about tire sizing, but I would confidently state the following:

Brown's Law Of Tire Sizing:

If two tires are marked with sizes that are mathematically equal,
but one is expressed as a decimal and the other as a fraction,
these two tires will not be interchangeable. (well, there are three exceptions, noted in the tables below...)

bikeme

If you find a different 2.1 or even a 2.2, check where the brake pads hit the rim once it's mounted. Sometimes a different tire in the same size or a bigger one will get its sidewalls cut upon braking as the pads may touch the tire as well as the rim. Adjust the pad angles as needed.

Alzerbster

Yes kind of confusing. How is 1.75 and 1 3/4 different sizes? Why isn't there a standard for bike tires, as there is for auto tires?

andrewclaus

I was just going to point this out, to be careful about decimal vs fraction sizes. The more you look at it, the more confusing it gets. Available tire sizes barely fit on one page. And by the way, 29er tires go on a smaller rim than 27" tires.

Miele Man

Don't worry about any tires with a fractional size. Your 26" tires are on a decimal size wheel and thus any decimal size 26" tire should fit. Reading the original post, I don't know why someone introduced the fractional size as it was irrelevant.

Just for information though. A 26" wheel with a fractional tire is a larger diameter wheel than a 26" wheel that uses a decimal tire.

Standards are great and that's why we have so many of them. LOL

Cheers

JohnDThompson 

There is a standard, and tires manufactured in the last couple decades should be marked with ETRTO size designations in addition to the deprecated and confusing 26" x 1-3/4 or 26" x 1.75 markings.

The ETRTO size designations look something like this: 45-559 or 38-590. The first number in the ETRTO pair is the nominal tire width, and isn't terribly important as rims can accommodate a fairly wide range of widths; frame/fork clearance puts an upper limit on this value. The second number is the tire bead seat, and this must match the rim or the tire won't seat properly. Find the ETRTO size designation on the old tire and choose a replacement with a nominal width reasonably close to that of the old tire, and a bead seat diameter identical to that of the old tire.

WizardOfBoz

Sheldon Brown thought it was relevant. The OP stated that he had been a bit confused by this. Why would more info, that helped the OP, be irrelevant?

Aren't you answering your own question here? There are two standards that differ by having one expressed as 1.75 and the other 1-3/4, an issue which has caused inconvenience to more than one person replacing a tire. You knew that the dual, similarly labeled standards existed. The OP didn't.

Why in the world would you write a dismissive post about a message that was meant to be helpful, and that the OP apparently found helpful, and that other forum members thought useful?

Miele Man

The OP didn't seem to be confused UNTIL someone else mentioned the fractional size of 26" wheels and tires.

Sometimes a post that's intended to be helpful can cause confusion instead.

Cheers

Alzerbster

Before the Sheldon Brown info was posted, I had read that information about tires on his website, and yes it confused me more. No big deal, I just bypass things that seem confusing and look for other info. Thanks all for helping to answer my question. I just got reintroduced to biking last year, after I retired. I found this forum, and its a great forum to get information from. Seems as though there are lots of seasoned bikers here, that offer lots of good information.

My bike has 700x35 tires, and the sizes that fit my bike just make more sense.
I passed on the info to my son, and he ordered a pair of 26x2.0 tires.