I have an older road bike with 27" wheels ... I'm wondering, why did the road bike world move to 700c? Is it more efficient, or does it stay true better, or what?

Thanks!

It's metric.

The U.K. and the U.S. were the only countries using inches. Now the U.K. is using metric measurement. There was no reason to continue manufacturing wheels in different sizes for different markets, and it probably saves the manufacturers money throughout the industry to have one standard size.

quote:and it probably saves the manufacturers money throughout the industry to have one standard size...yeah, but if there's one thing the bike tire industry DOESN'T have, it's standardization. Check out Sheldon Brown's site about tire sizes, it's mind-bogling. Anyhow, ranting aside, another big reason is that the 700C clincher is (supposed to be) the same diameter as the standard sewup/tubular. Big benefit for both the bike builders and especially for racers since you could easily swap one for the other and leave the brakes as they were...say, if you wanted to train on clinchers but race on tubs. And the first lightweight clinchers were French products (Module E and Rigida) so they were certainly going to make them metric, metric IS French.

I know. However, the vast majority of bikes come in two flavors: 700c, and 26". Now, let's take one manufacturer making one model. Let's say the ACME GoFast. Instead of making some bikes for the American market, with cantilever posts set at 27", and some bikes for the European market, with cantilever posts set at 700c, ACME makes all bikes the same. ACME only has to make one bike (albeit in different frame sizes), and can sell that bike anywhere in the world. That results in lower costs for ACME.

See what I mean? Standardization results in benefits for both the manufacturers and consumers.

True, but to me the ultimate irony is that the one surviving bottom bracket standard is 1-3/8" x 24 TPI. The Swiss standard made the most sense by far, being a purely metric 35x1mm, with a self-tightening left-threaded fixed cup, but it's the rarest of all. Go figure ...

Actually, it didn't. The "road bike world" was using that size since the 19th century. Dunlop introduced the 630 mm (27 inch) size sometime in the 1950s for marketing reasons, but it never caught on outside of English speaking countries, and in the 1980s it was pretty much abandoned.

Right.

Sheldon "Does Anybody Else Have A Rambouillet With 630 (27 inch) Wheels?" Brown

Strange. If that's the case, then why do so many road bikes from the 70's and 80's have 27" wheels? Even models made outside the Imperial measurement dynasty? For example, I had a Takara. That's not Takara, Kansas if you know what I mean.

If it was imported to the U.S., then it was made with 27" wheels for the U.S. market. I would bet that the same bike in Japan would have had 700c wheels. The change to a standardized wheel size allowed Takara to make one version of its models for sale in every market, instead of different versions for different markets. I would also bet that all those 27" wheeled road bikes were either made in the U.S., or made for the American market, and if they were made for the American market, and sold at home as well, there are 27" versions, and 700c versions.

Lot's of 1970's bike frames could handle both 27" and 700c wheels and if the right brakes were used they bike could handle either just by moving the brake pads. I have three such bikes. So the manufacturer only had to stock two sizes of rims and possibly different length spokes and then make sure the correct wheels got on the right ships.

That is what makes older bikes so versatile today; they have the clearances to handle skinny tires on lightweight wheels for racing and with just a wheel swap you can go fat and bomb on dirt roads.

Its interesting to note that its still easier to find 27" tires and tubes in the US -- they're in every Walmart/KMart/ACO Hardware. Walmart even stocks a $9 27" tire with reflective sidewalls. You won't find 700c stuff anywhere but an LBS.

Funny though that Bell (the tube brand you'll find in WM most of the time - rebadged Chen Shing), offers a 700C tube w/Presta valve - all their boxes show it on one side, and the color-code of these boxes are teal, yet, I've yet to see one WM that carries them.

-Kurt

Which, other than eBay, a yard sale, or a mail order bike shop, is the ONLY place I would consider shopping for bike parts, including tires.

So, can you replace 27 inch tires with 700c tires, or 700c wheels and tires?

DD74,

Yes. It's an easy swap. My '68 Peugeot has gone to 700 x 23's instead of the original 27 x 13/8. Made the bike steer significantly quicker and a little squirrelly. But I recommend it.

Tyson
Cushing, Oklahoma

Yes, as long as the brakes are long enough to reach the wheel rims. When I converted an old Fuji 10-speed to fixed gear, I also replaced the 27" wheels with 700c. Had to find "long arm" nutted (not recessed nut) brake calipers. Rears worked OK, I had to dremel out the slots for the brake pad bolts to reach on the front.

This is a very euro-american centric view of things. I had a very knowledgable person tell me recently -- and I have no reason to doubt it -- that more 26 x 1 3/8ths inch tires are produced than all other tire sizes combined.

No. Yes.

622 mm (700c) tires will not fit onto 630 mm (27 inch) rims. No way.

622 mm (700c) wheels and tires will fit on a bike made for 630 mm (27 inch) wheels, but you will need to be able to lower the brake shoes by 4 mm. Depending on your bike and your brake calipers, there may or may not be enough adjustment room available. That's the only problem with this conversion.

Sheldon "ISO/E.T.R.T.O." Brown

As others have already said, yes. Now, I'll stretch this statement a bit further:

My 64 Raleigh Gran Sport came with steel 27x1-1/4 wheels. As was my habit in the old days, I immediately replaced them with a set of 700c tubular wheels, and of course loved the difference.

Six months later, I get this Gitane Tour de France, minus wheels. To get it on the road, I transfer the wheels from the Raleigh to the Gitane.

Now, due to some other dealings, I've got a set of 27" clincher wheels on the rack, narrow (1/2" cross section) Weinmann rims. I put on a set of 27x1 - 110lb pressure tyres on them, and I'm not losing too much performance vs. the tubulars. They're way better than classic 27x1-1/4s, I just dread the thought of getting a puncture on the road. Those tyres were a real pain to get on.

So it is easy to get like performance between 27" and 700c wheels - if you're ready for a few tradeoffs.

Syke
Deranged Few M/C

Um, I'm not sure if he meant to be, but I think Dynamic was asking if you can swap different-sized tires, not wheels. I've never tried doing this, but--and someone can confirm or correct this--I'm pretty sure that it won't work. You have to match the tire BSD (i.e. the 'size', 27" or 700c) to the wheel: if you have a 700c wheel, you have to put on a 700c tire, same with a 27" wheel and tire (they have to match). I've recently inquired as to whether the width of the tires have to match the width of the wheel, and the general response I got was that it does not: as long as you have the right BSD size, then the tire will fit. (But note if they're 27" tires with smooth sides, no hooks on the rims, then you have to also deal with that. There's a thread in the past week about this question.

Converting wheel sizes, on the other hand, while a far more involved endeavor, can be done according to the guidelines given by previous posters. Main issue is brake reach (you also have to confirm hub spacing, but that usually isn't a problem).

I was just pointing out that 27" is still easy to find in the places most Americans shop. Not that I'd buy them there, but its nice to know I can find up a 27" tube if I need one in a hurry (or on the road).

Although conversion to 700c can be easy it is my opinion that the rewards are so negligable that it's only worthwhile if 1. You can keep your present brakes and 2. You need new rims anyway. Otherwise, just buy nice 27" tires on your bike and enjoy them.

(I realize there are exceptions to this statement. Such as already having longer reach brakes and an extra set of wheels in parts bin waiting to be put on a bike.)

Thanks! That's the answer/ perspective I was looking for! As usual, you rock!

I happened to buy a 27" tube from WM and I'm sold on it.

I went through a few $6 tubes for my 27x1.25" Arayas with Continental UltraSport tires. A couple of weeks ago, after a flat (that happened overnight so I wasn't stranded anywhere), I didn't get around to replacing the tube until late, and the only place open was Wal*Mart, so I gave it a shot. The Bell tubes there were like $2.50. At that price, I bought a couple of 27" tubes so I'd have spares. The box advertised the tube as having "air lock" technology, which I didn't think about at the time. But after two weeks, I am putting MUCH LESS AIR into the tube to keep it at about 106psi. I'm happy with the product. And it doesn't seem to be inferior to any Pyramid or Continental tubes I've used.

I apologize for my ignorance. I'm not sure I'm getting this straight. I have an old custom-made chrome-moly frame which uses 27x1 tires on 27 (I presume) rims. I have a 105 brake set. Should it be easy for me to switch to 700c should the need arise, and keep using my Shimano 105 brakes?

Switching from 27 inch to 700c rims requires adjusting the brake pads about 4mm. Most (but not all) brake calipers make such an adjustment quick and easy.

Why did 700c "win" over 27 inch? I suspect just luck. Sew-up tires for racing bikes just happened to be the same size as 700c clinchers. So, a guy could use 700c clinchers during the week for training and 700c sew-ups on Saturday for racing and not have to readjust his brakes.

And, road bikes are all about "racing" (for 1% of riders) or having a bike that resembles a real "racing bike" (for 99% of riders). So, if racing bikes used 700c, it was a sure thing that even the cheapest road bike would eventually have to have 700c rims.