ForlornEnemy

I notice that many older road bikes (pre-90's) have bigger tires than modern ones. I looked on the Sheldon Brown website and I believe these are called "27s"... but I have questions. Can a modern 700c tire fit on these older rims? If not, is a modern wheelset usually compatible with these bikes? I am finding loads of info online but not for these specific questions. Thanks for any help...

jeepr

27" tire will not fit a 700c wheel. 700c wheels are USUALLY compatible with older frames. The biggest problem is the reach of the brakes. I have converted several to 700c without issues.

late

The cheap thing is to get a good 27 inch tire and call it a day.

But the new wheels are nice. Take it to your bike shop and
see what they have to say. I'd try to keep the overall size of the tire similar
to the one on there now (IOW, if it's a medium width tire, get the new size,
and in a similar width)

ironwood

Modern road wheels might have 130mm rear dropout spacing , while older bikes have a 126mm rear dropout spacing. Some people say it won't hurt to squeeze a 130mm rear wheel in a 126mm dropout, others say cold set the frame. This only applies to steel frames

garage sale GT

27x1-1/8 tires are 28mm. 27x1 tires are 25mm. That's pretty close to modern 700x23mm tires and both sizes are still available new.

It may be a deep section aero rim you want, if you like the modern look, but I don't think you can get a wheelset that has them without a 130mm hub unless you go custom.

I have tried a 130 hub in a 126 frame and it kept sliding forward when I pedaled. You can't just recklessly increase the quick release skewer tension because you'll ruin the wheel's bearings.

I think people raced on tubulars back then so even the racers put pretty wide training tires on their 27s because they would swap them out for tubular wheels on race day.

fietsbob

A rim standard so tire makers and rim makers are talking to each other, has been reached.

27"=630, 700s = 622, it's a diameter , so 1/2 that is 4mm.
your brake shoes have to come down that much, in their adjustment slot.

juls

I've never seen a 27" tubular wheel.

fuzz2050

I've had no trouble putting 130mm hubs into 126mm frames, or even a 135mm hub, although that one did take more muscle. You shouldn't need more tension on the quick release.

scozim 

Same here - heck, the tension of the frame being set at 126mm should actually help. I have one bike I ride with 27" wheels and my kids have two. They roll and ride quite nicely. You can still get decent tires for them. So, as long as your wheel is good why not keep it, slap some tires on it and see what you think.