630 mm used to be the US road bike size standard; nowadays its 622 mm and 597 mm was an oddball Schwinn size. 587 mm was an oddball GT size.

597mm was the standard size for British club bikes until around 1950. I figured you'd have known that, NormanF, with your love for Path/Club bikes.

And now a 28 is a 700 from Germany lol

Of course but today are practically obsolete. My last path bike had 635 mm wheels, the last size any one is still making tires to fit them. That would be Schwalbe.

On German sites, 28 and 29 are used interchangeably to refer to 29ers.

Schwalbe still makes 597mm/EA1 tires, too:

SCHWALBE HS130 26 x 1 1/4 (32/597) :: £12.00 :: PARTS & ACCESSORIES :: Tyres - General :: Spa Cycles, Harrogate - The touring cyclists specialist.

You could get alloy wheels custom built off your existing all steel wheelset. I guess they would lighten the weight and stop well in the rain.

571 also was used on some roadsters and utility/cargo bikes, but with balloon tires: 54-571 or 26 x 1 3/4 x 2.

Actually, motor vehicles have their own version of stupid mixing of measures....why is the wheel size in inches, and the rest of the tire dimensions in millimeters? I recall Michelin tried to introduce the metric radial over 30 years ago, and it wasn't accepted.

Back in the early '70s, 26" wheels were used on Western Auto and cheap department store bikes and 27" wheels were used on more expensive bikes.

Don't forget size of the rider. It gets complicated, doesn't it. Suppose we decide that people over 6'2" (188 cm) tall really need to be riding 30" wheels. Should we make a new standard for them? Should adults buy bikes sized not just in frame sizes but wheel sizes? I hope not. It's bad enough that there are 12", 16", 20", and 24" wheels for kids.

And have you ever noticed how bad most 24"-wheeled kids bikes are? I'd try to keep a kid on a 20" bike as long as possible until she's ready for 26".

I think it has more to do with the fact tires are marketed as 27", 700C, 26" etc. If you walk into a bike shop and say your looking for a 25mm wide 700C tire, the guy goes to the wall and grabs it, if you say your looking for a 622-25 tire, many of them will look at you funny. I've seen adverts for mountain bikes with 27.5" wheels, even though it's been called 650B for decades and 29" is really 700C with a fat tire. Americans have trouble with 622-63 but have no trouble with 29"x2.5" even though it's the same tire.

In a US-centric sort of way.

Do you mean "it was already the dominant wheel size in the rest of the world" or "it's only dominant in the US"?

Just because it's so complicated, the solution would probably need an advanced computer model or CAD simulation. Bug I might add that this is in theory. I am interested in the creative part. Not to make things worse.

In the US auto industry there is an engineering society, Society of Automotive Engineers, where practitioners (car folks and for example tire folks) have banded together to knock out a raft of agreements on such matters. They also host golf outings, lectures, dinners, awards, conferences, and all that other clubby stuff.

The auto companies, wanting to have simple procurement processes that actually work, have usually set policies that where there isn't a good reason not to, SAE standards ("J-documents") must be used. The credibility of SAE also gives the company lawyers something to anchor their claws onto ("We followed industry good practices," et cetera) as they survey the incoming threats.

Other than in the USA there are national and continental standards bodies that serve the same purposes and sometimes agree with SAE. Because the industry is so huge, any released (accepted, agreed, recognized) standards really have a lot of effect. In some cases national safety standards enforced by say, the National Highway Traffic Safety Administration (which have legal strength), have followed SAE standards and research. In a few cases ISO has developed international standards on topics that SAE has addressed and vice versa. But the ISO standards are usually recognized for their technical authority and generality, but are not usually made into regulations in the USA. SAE makes an attempt to be consistent with ISO.

Anyway, no such adherince to standards is true in the bike industry. ISO and some national standards exist, but for the most part cottage builders (like the thousands of custom and bespoke frame builders) are free to have their own ideas and to sell what they think works. It's a much more free market in the wild bike world. But "let the buyer beware" is still an important point, as a result.

Another interesting point: tubulars (sometimes called "sprints" in the UK) can be found marked "27 inch." But they still fit what is known in the USA as a 700c tubular rim. And the 700c tubular rim is called that because its brake track is in the same position as the brake track of a 700c clincher rim. Therefore a set of tubular rims (your race wheels) could be readily interchanged with a set of 700c clincher wheels (your training wheels).

I have no doubt that a creative engineer can come up with an optimization process and program it, but the range of factors must be weighted. Do you prefer traction, cushiness, speed, efficiency, flat resistance, or what? I think the "optimized" result would be different for different rider preferences.

But it might be a fun on-line toy for bikie nerds!

Yes! ;)

The Michelin TRX - it was still measured by bead seat diameter. The TRX required a different shape of rim, which is why Michelin choose to introduce different rim sizes so that it was impossible to install a TRX tire on a regular rim.

Old article but an interesting perspective by a manufacturer president:
700c vs. 26"

Outdated but sort of gives an insight how riders and manufactures think and steer the market.

As for myself, scary thought of having bikes with just about every assortment of tire size and type. Old, new, road, knob's, tubulars, clinchers and even tubular/clinchers, 20, 24, 26, 27, 28, 700c. And then there's the LBS asking about my 'exclusive Schwinn' size and not by dimension...LOL.

And lets us not forget the Venerable ISO
[h=3]26 x 1 3/8 inch (590 mm) [/h]

I dunno. My friend Todd didn't seem to have a problem:

http://www.utahtrikes.com/uploads/ut...0167260686.jpg

With regards to road bikes, 700 was and is dominant in Europe. The US had a 27" fling for a while before they came back to the 700.

You should try to find tires for a 36er.

http://www.bikeforums.net/attachment...4&d=1405204312

http://bikeforums.net/attachment.php...hmentid=392834