why the switch?
 

Man, I can't believe I want through all that registration for one silly question, but this has been bothering me. Does anyone know why road bikes switched from 27" to 700c? Anyone that works as a mechanic long enough accidentally grabs a 27 and when installation is attempted one finds that it is significantly larger than a 700c.
With all this hoopla about 29ers and bigger being better, why not the 27? Was it due to the quicker acceleration of the smaller wheel? Some kind of industry induced standard? The rest of the world snubbing the U.S. for its rejection of the metric system?

A 700c clincher wheel is interchangeable with a tubular wheel. Better bikes have always been built this size.

The switch to 700c clinchers in the U.S. coincided with the introduction of better lightweight bikes.

Probably best to start with Sheldon Brown on Tire Sizes

Now can anyone tell me why the switch from 8-track sound systems?

Simple! Can't rewind 'em!!!!

27" was a British/Imperial size. 700c is a French size.

This time around the French sizing system won out. Back in the day when I started racing I was using 27" tires for clinchers and the tubular/single tires were all French (700c) sized. You generaly could use either sized wheels/tires in most frames although there is a 4 mm diameter difference. Using 700c clinchers AND 700c singles is way more convenient so I guess it won out.

Regards, Anthony

FWIW, 29ers and 700c have the same diameter (622 mm). The only difference is that 29ers are wider. In contrast, 27" has a 630 mm diameter.

The Metric Conversion Act of 1975 decreed that everything would be converted to metric by 1985. It was only after it was discovered that The New Math taught in the early 70's had failed to equip children to multiply and divide by ten that the whole idea was abandoned. You youngsters won't remember these.

http://lamar.colostate.edu/~hillger/...am-freeway.jpg

I think that would the one;)

[QUOTE=wanders;5662833]The Metric Conversion Act of 1975 decreed that everything would be converted to metric by 1985. It was only after it was discovered that The New Math taught in the early 70's had failed to equip children to multiply and divide by ten that the whole idea was abandoned.[QUOTE]

Here is my theory. Young people picked up the metric system with out much trouble. The real culprit was the older people. They were not in school, so were never "forced" to learn metric. I remember my Mother griping about not understanding the metric system. Older people just also happen to be the same group that are the lawmakers. So instead of learning, they changed the law.

Also the idea of putting both measurements on everything sounds good on the surface, but it is nothing but failure built in. Why learn how far 6 kms is when 4 miles is posted right there? If we put Chinese and English on everything are you going to learn Chinese?

Dumb question...how is 700c prononced? and what does it mean?

A) "seven hundred see" is how I say it.

B) It was a French size. There was also a 700A, B, and D size. See the link to the sheldon brown website in the first reply for details.

I blame the failure of the metric system in the US on the attempt to use the inferior celsius scale.

I blame the failure of the metric system on The Captain and Tennille

But I could be wrong.

I blame it on The Count on Sesame Street....stupid immigrant.

Yeah, heaven forbid that the temperature scale makes any sense:rolleyes:

700c or 650c ect aren't metric sizes actualy. 700c is ISO (or metric I suppose) 622 mm BSD (bead seat diameter)

Regards, Anthony

All rim dimensions for everything from aeroplanes to wheelbarrows are set by E.T.R.T.O. ISO has nothing to do with it.

622 is a figure that is calculated and not actually measured, according to the procedures and using the specific tools described, in detail, within the E.T.R.T.O. book. I have the latest edition sitting on a shelf next to my desk. It is a mind numbing read but something I need to be very familiar with in my work.

Again, for those who haven't picked up on this the first 20 times I mentioned it, ISO has nothing to do with setting these standards.

I know there are old rims with ISO written on them and I know ISO is listed on Sheldon's site but trust me, it's E.T.R.T.O. all the way.

Perish the thought that it have a useful resolution. :rolleyes:

Their origin =is= metric, but that's just quibbling.

No, EVERYTHING is George W. Bush's fault.

thanks....that makes it clear. I wanted to make sure it didn't stand for something other than "C" to differentiate from "A" and "B". I felt stupid walking into the LBS talking to them thiniking the whole time I was saying it wrong and waiting for them to correct me:D

Exactly! And George W. Bush is the other George Bush's fault.

Thanks to the mods for deleting my posts without telling me. Good job! Great forum!

A real noobie question:

What's a "clincher" wheel versus a "tubular"?

Setting temperatures relative to the freezing and boiling points of water are just slightly less arbitrary than those used by Farenheit (0 set a the lowest temperature achiveable in the lab at that time, a mixture of ice, salt and water, and 12 set at body temperature, later sub divided by 8 to become 96, and later still adjusted to 98.6 as accuracy improved). The Celcius scale, as anyone who's traveled to Europe knows, lacks the resolution of the Farenheit scale so it's more difficult to tell if you need a sweater or jacket outside.

If we want to get technical they both suck. Kelvin and Rankin are the only two REAL temperature scales. :)

:lol:

Hmm I wonder if Kelvin and Celsius have any similarities?

Well, I'd rather get stuck in 0 Celsius weather than 0 Kelvin. :)