how close are 27 to 700cc?

[10timesbetter]

I already did a search, and couldn't come up with anything, so sorry if this has been covered numberous times before, but i didn't find it before,

but....exactly how close are 27 inch wheels, and 70cc wheels? i have a schwinn world, with 27inch tires, been fixing it up since i've gotten to school about two months ago, and it's doing pretty nice, but my goal has been to slowly replace parts, keeping the old parts, to the point that hopefully in spring, i can buy a new frame, switch all the nice parts over to it, but all the old parts back on the schwinn, then just have that for a crappy weather bike, but next i'm trying to find a decent fork, and if i found one for 700 wheels, would a 27 inch wheel fit in it? i know the newer forks usually run right up next to the wheel, where as my setup now has a good inch or two in there, so if the 27's are smaller it'd probably fit, if they're bigger it'd rub i'm sure, 27 should be smaller by my calculating, but i've been told it was the other way around, so i wasn't sure if they just made a mistake, or if maybe one was measured by the outside ofthe tire, one by the rim, or who knows, i've just been curious about it for a while,

 

[531Aussie]

I don't have the exact dimensions, but....

27 inch wheels are bigger than 700c.

Most new frames and forks should cope with 27 inch wheels, especially the forks, but you've gotta make sure the brakes are short enough. Many new frames have short chain-stays (~40cm), so a rear 27 inch wheel could rub on the seat-tube.

The only problem putting 700c wheels in an old frame is that you might
need longer brakes.

 

[boudreaux]

Most new frames and forks should cope with 27 inch wheels, especially the forks,

BS!................

 

[boudreaux]

I already did a search, and couldn't come up with anything, so sorry if this has been covered numberous times before, but i didn't find it before,

but....exactly how close are 27 inch wheels, and 70cc wheels? i have a schwinn world, with 27inch tires, been fixing it up since i've gotten to school about two months ago, and it's doing pretty nice, but my goal has been to slowly replace parts, keeping the old parts, to the point that hopefully in spring, i can buy a new frame, switch all the nice parts over to it, but all the old parts back on the schwinn, then just have that for a crappy weather bike, but next i'm trying to find a decent fork, and if i found one for 700 wheels, would a 27 inch wheel fit in it? i know the newer forks usually run right up next to the wheel, where as my setup now has a good inch or two in there, so if the 27's are smaller it'd probably fit, if they're bigger it'd rub i'm sure, 27 should be smaller by my calculating, but i've been told it was the other way around, so i wasn't sure if they just made a mistake, or if maybe one was measured by the outside ofthe tire, one by the rim, or who knows, i've just been curious about it for a while,

You are just trying to whizzzz up a rope here. Ride the Schwinn, buy what you want in the spring and stick it together,and save alot of hassle.

 

[capwater]

You're going through all this hassle and expense just so you can use your old 27" wheels? You're nuts. You are never going to make it cost effective to buy a new bike piecemeal.

 

[10timesbetter]

no, my plan is to get a second bike with 700cc wheels, I was just curious if new wheels would fit in this bike, I can get them and just wait until spring, but i'm not the kinda person who likes to spend money on something, and let it sit around for months until i get to use it, if i bought a new fork or wheels, i'd probably end up gettin gbored and try to put them in the bike i have now....

 

[531Aussie]

27 inch wheels are about 8mm bigger in diameter than 700c.

 

[ritcho]

I already did a search, and couldn't come up with anything, so sorry if this has been covered numberous times before, but i didn't find it before,

but....exactly how close are 27 inch wheels, and 70cc wheels? i have a schwinn world, with 27inch tires, been fixing it up since i've gotten to school about two months ago, and it's doing pretty nice, but my goal has been to slowly replace parts, keeping the old parts, to the point that hopefully in spring, i can buy a new frame, switch all the nice parts over to it, but all the old parts back on the schwinn, then just have that for a crappy weather bike, but next i'm trying to find a decent fork, and if i found one for 700 wheels, would a 27 inch wheel fit in it? i know the newer forks usually run right up next to the wheel, where as my setup now has a good inch or two in there, so if the 27's are smaller it'd probably fit, if they're bigger it'd rub i'm sure, 27 should be smaller by my calculating, but i've been told it was the other way around, so i wasn't sure if they just made a mistake, or if maybe one was measured by the outside ofthe tire, one by the rim, or who knows, i've just been curious about it for a while,

27in = ISO 630mm
700c = ISO 622mm

Ritch

 

[10timesbetter]

thanks, that's what i thought, the kid i talked to must've just gotten it backwards, i could figure out the acctual size compairisons myself, but i wasn't sure if they just started measuring them by a different part of the wheel or anything like that,

 

[JudeChow]

I have the problem..i got an older bike...Apollo MKII ..i checked my breaks and they can move down 1 cm more...does that mean 700cc rims will fit???
Furthermore I see someone mentioning about upgrading to cantilever?..how much is the process if I just want a set that works...nothing great performance wise etc...???

 

[dgregory57]

I have the problem..i got an older bike...Apollo MKII ..i checked my breaks and they can move down 1 cm more...does that mean 700cc rims will fit???
Furthermore I see someone mentioning about upgrading to cantilever?..how much is the process if I just want a set that works...nothing great performance wise etc...???

I will assume that your bike use 27" wheels now...

With a diameter 8mm smaller on the 700c than the 27", all you need is an additional 4mm of brake reach, so you should be good to go.

The rear spacing may need to be a little wider depending on the hubs you are changing from and to... but probably not a show stopper, especially if your bike has a steel frame.

It is a lot of work to convert to cantilevers if your bike doesn't already have cantilever bosses. So, unless you have a compelling reason to move to cantilevers, stay with what you have.

 

[mikesbytes]

I already did a search, and couldn't come up with anything, so sorry if this has been covered numberous times before, but i didn't find it before,

but....exactly how close are 27 inch wheels, and 70cc wheels? i have a schwinn world, with 27inch tires, been fixing it up since i've gotten to school about two months ago, and it's doing pretty nice, but my goal has been to slowly replace parts, keeping the old parts, to the point that hopefully in spring, i can buy a new frame, switch all the nice parts over to it, but all the old parts back on the schwinn, then just have that for a crappy weather bike, but next i'm trying to find a decent fork, and if i found one for 700 wheels, would a 27 inch wheel fit in it? i know the newer forks usually run right up next to the wheel, where as my setup now has a good inch or two in there, so if the 27's are smaller it'd probably fit, if they're bigger it'd rub i'm sure, 27 should be smaller by my calculating, but i've been told it was the other way around, so i wasn't sure if they just made a mistake, or if maybe one was measured by the outside ofthe tire, one by the rim, or who knows, i've just been curious about it for a while,

Problems with slowely replacing the parts, is 1. compatibility, not all parts fit all bikes. 2. cost. It is a lot cheaper to buy a complete bike, than to buy the parts individually. 3. result. You could find that the bike with the parts gradually replaced will not be as good as a complete new bike.

BTW I had a similar situation, a 27" frame with 700c wheels and I had problems with the reach of the brakes.

 

[Don Shipp]

I have had the same bike for many years and nearly every part of it has been replaced several times, always with an upgrade. It was a 10 speed with 27" wheels, but is now a 27 speed with 700c wheels. What made this possible was that I never went over to indexing, so the Shimano/Campag/whatever parts could all work with eachother.
I am not saying that this would be possible for any bike, it depends partially on the tolerances.

 

[mikesbytes]

Sorry, I should of clarified what I meant by compatibility. It's not that you can't get the parts, as there are parts for pretty much anything out there, more of a case that you want the latest bit and it don't fit your retro bike.

My spare bike is a 1980's steel frame bike that looks like a heap of s**t and is a collection of parts rescued from the succession of good bikes that have suffered death. Goes a lot better than it looks, so it can be fun blasting past guys on flash bikes on the way to work, but I wouldn't like to ride it in a weekend bunch ride, not as confortable a modern bike.