Fissile

I tried to find the answer to this question at Sheldon's site, but no luck.

It's my understanding that 700C wheels came first and then the 27 inch wheel and then back to 700C. My question is this: Why did manufacturers switch from 700C to 27 in the first place? The difference in diameter is only 8mm. Were there any real advantages to increasing the wheel size by such a small amount? Or was it just for purposes of marketing hype? "Look! New and improved!"

rootboy 

Good question. No answer other than I figured 700c was a Euro metric thing , and 27 inch was an Imperial thing. Which is too obvious and stupid, but hey...

Fissile

But 27 "inch" is metric, it's actually 630mm.

Ex Pres 

I think the British introduced the 27" because they didn't want to be French.

dbakl

700 is the same size as tubulars, allowing one to switch easily between tubulars and clinchers without resetting brake pads. That's how we did it in the 70s.

Fissile

I should have known this came from the diseased mind of an Englishman....like driving on the wrong side of the road and building cars with positive ground electrical systems.

rhm

27 x 1 1/4 was a proprietary size introduced by Dunlop in the 30's. Dunlop made both rims and tires, and the idea was that they would corner the market on high end clinchers. They became increasingly common in the 50's, eventually supplanting the 26 x 1 1/4 size that had previously been popular.

I don't know when 700c clinchers were introduced, but I'm pretty sure the same size tubular tires (28", "sprints") had been around for years by that time.

sykerocker 

You must have lived in a more urban area than me. In Erie, PA, you had the choice between 27" clincher (99% of those riding), or 700c tubulars (myself and one or two other crazies). None of us had ever heard of 700c clinchers back then, none of the catalogs that came in to the bike shop where I worked offered anything in 700c clinchers. It's only when I got back into cycling after one heck of a long absence that I heard about 700c clinchers, and I'm still not really clear as to when the one transitioned into the other.

At least sewups are forever. Which is one (of many) reasons why I still ride them.

sykerocker 

The Napoleonic Wars (hell, the War of Spanish Succession) hasn't been entirely settled yet in some national minds. It was a real shock that England and France actually allied together to go to the Crimea. That was a political equivalent of hell freezing over. The English do it their way, because back then their way was better.

prathmann

Certainly not the only example of different groups each wanting their own unique size. Just look at the whole list of different tire sizes on Sheldon's site. I remember as a kid that Schwinn bikes had their own size of 26" tires that were incompatible with everyone else's 26" tires. Similar to 27" vs. 700c, the Schwinn rims were just a little bigger - looked the same but you could struggle for a long time trying to get one of the other 26" tires to fit on a Schwinn rim.

When 10 speed bikes (2 in front, 5 in back) first became popular in the US the tire size was 27" for clincher rims and 700c for tubulars. Then 700c clinchers allowed racers to quickly switch wheels without having to adjust the brakes and the popularity of this size gradually increased.

Fissile

Is that it? I was told that the 700c made a comeback because most of the 27" clinchers did not have hooked rims. As tires improved, and it became possible to make skinny high pressure tires, the bike makers wanted to avoid the liability of people placing high pressure tires on rims without hooks. Since there were hardly any non-hooked 700c clinchers in existence, they went back to that size for hooked rims.

sykerocker 

Which, so far, is the first logical reason I've heard for the switch-over.

Fissile

According to member rhm, the original reason for the switch to 27" was because Dunlop attempted to seize the lion's share of the road bike tire market by producing a proprietary tire size and a rim to utilize said tire size. They probably offered a good deal to bike makers on both rims and tires, knowing they would get a lot of the biz for replacements. So it's like I assumed, the original reason for the switch to 27" was marketing, and the slight increase in sized offers no real advantage.

kc0yef 

Different spokes for different parts of the world
They didn't have much air mail package service and the internet in those days

garage sale GT

There were plenty of hook bead 27" rims and tires marked for use only on a hook bead rim, so they didn't sink the 27" size to avoid blowouts.

I think British makers just got a lot less important in the 1980s whereas French, Italian, and other foreign makes got more important.

Mr IGH

I worked in a high-end LBS/custom frame shop starting in 1976, I remember 700C clinchers starting to be used in the late 70's when Rigidas became widely available. Even then, most riders of fancy bikes preferred sew-ups and no USCF riders trained on them (except winter). I had a set of 700C Rigidas with Campy track hubs for winter training and to ride to school. Once the Avocet/Specialized tire wars started in the mid 80's clinchers started to replace sew-ups for most riders.

dbakl

No, small college town in CA. But there were lots of kids from the big cities who knew what was what. My mentor and riding buddy was from LA, sold me my first good frame, taught me how to build it, loaned me his tools and told me about them. The local bike shop that catered to the serious cyclists carried them circa 1972. First wheels I build, to save my sewups for the weekend rides. During the week it was how I got around: no car until I graduated.

dbakl

Hmm, as I remember the old Weinmann clincher rims are one without a hook edge, but I think they were only 27". Rigidas and Super Champions were the clincher rims I remember, the same except for size. Still use them today when I can find on ebay, just built a pair of Super Champion in 27".

Honestly, for me, I choose whatever is going to fit the bike the best; sometimes its 27". Need to build up a set of Rigida 27" next.

garage sale GT

I have heard that tubulars marked 27" were actually the same size as 700c.

When raceable clinchers were developed, maybe it was too expensive to create two nearly identical tire sizes for no avail, especially since most 27" raceable bikes were probably already capable of taking a 700c tubular and race tires are made in smaller numbers which doesn't justify several different sizes as easily.

The market is race driven so everything went to 700c although 27" and 26x1-3/8" plodded on for a while because manufacturers were already set up to make the wheels and training, touring, or low-end tires for them.

27 only got started back in the days when more stuff was proprietary and I guess Schwinn chose to adapt the English size. That one decision probably affected a lot.

So, anyway, that's my wild guess.

randyjawa 

Long have I wondered about this, and many times have I asked others the questions being presented here. As I understand it, clincher 700c rims were released in 1976 for the first time. Prior to that, you could choose between 700 tubulars or 27" clinchers. However...

This old Torpado came fitted, originally, with 700c steel hoops, believe it or not and my best guess about the vintage of the bike would be late sixties or early seventies. Anyone else care to guess at the vintage for the Torpado.

As for the huge popularity of the 27" wheel, I would suggest that it became solidly established as a result of two things. The Bike Boom and the fact that one of the biggest markets in the world, the USA, measured everything in Imperial rather than metric units. Canada, also was a big market, once again opting, most of the time, for the 27" wheel sets.

Please keep in mind, I have never found anyone who actually knows the answer to when did 700c clinchers begin. What was the first 700c clincher. And why were there two standards - 700c and 27".

BHOFM

Doesn't that cause hair loss?

753proguy

Or Whitworth fasteners! Nothing like inventing a third nut and bolt sizing system that is neiter Metric nor Imperial!

You know why the Brits drink warm beer, right? Because they have Lucas refrigerators.... Bada bing....

(FWIW, I consider myself an honorary Brit. Lived there as a child. I was even called "English boy" for a while in middle school, back here in the USA, so hopefully it is OK for me to say these things).

garage sale GT

I really think I pegged it. There were two standard road bike systems because Dunlop introduced a proprietary one and some other makers picked up on it.

Their high end race machines could bolt on tubular rims for a race and train on 27" training tires, but even if they rode only tubulars, the "cool" still rubbed off on the standard 27" bikes. But the tubulars were actually the same size as 700c.

Then, when companies like Michelin started developing 700c racing clinchers like the famous E-type, it was too expensive to make a whole new mold for 27" just like it had been for tubulars, because racers aren't as big a market as casual users, commuters, touring riders, etc.

They could not rebadge 700c clinchers as "27 inch race tires" because someone was bound to notice they didn't fit the regular touring rims on a standard bike.

I think British makers were in a state of decline in the mid 70s and there wasn't a lot of interest in racing in the US so the biggest makers and users of 27s had no incentive to develop race tires and light weight rims for applications where the extrusion die or the tire mold may only be used rarely.

They may have sold race gear at a loss like the Paramount in order to promote the rest of the line so there may have been no money in it at all, only a question of how much you can afford to lose.

Makers like Raleigh and Schwinn continued to use their wheelmaking equipment for humbler lines but racing drives cycling and you could no longer point to the 27x7/8" badge on your 700c-size tubular and say you had the same type of wheel as a Varsity or Raleigh Record. Then, they changed hands and the equipment probably went to replacement parts makers as spares.

Fissile

And impotence.

garage sale GT

OK, latest version, the other two were way too complicated.

Dunlop never came out with a 27" racing tire or rim in the days of tubulars, they just rebadged 700c tubulars and rims. Probably wasn't enough business in it.

So, why should they start doing so with clinchers, in a decade when the British bike industry was declining?

But, they couldn't just rebadge 700c clinchers because someone would have tried them on his touring bike and everyone would realize the race tires weren't really the same as the touring and training tires, and the promotional effect would be lost.