Bicycle Mechanics - Hub spacing for old bike

I recently purchased an old Centurion Pro Tour 15 touring bike. It is 15 speed with five in the back. The rear wheel spacing measures 126mm on a Suzue Sealed Tech 40h hub with 27" tires. The bike is in pretty good shape. Would a road bike wheel in 130mm spacing work as a rear wheel in 700c. I have already put a 700c wheel on the front and was able to adjust the brakes to work just fine. I think this bike is a 1982 to 1984 vintage. My goal would be to increase this bike to a 21 speed. I will only be riding this bike on paved roads and will not use it for touring since I already have a nice touring bike. Thank you.

I'm currently rebuilding a Pro Tour myself, an '83. Sweet bikes! Mine has Suntour sealed hubs front and rear, so I suspect your bike is not an '83. Check out the date codes on your components and compare them to the ones at the www.vintage-trek.com site, you should be able to determine the year model if the components are original. T-Mar (bike forum member), on the Classic and Vintage forum, is an expert on Centurion serial numbers and could probably nail it down for you also............Anyway, yeah, going from 126 to 130 on the rear spacing shouldn't be a big problem, you can either squeeze it in each time you install the wheel or you could follow the directions for cold setting on Sheldon Brown's site and spread the rear triangle out to 130mm for easier wheel changes. The big problem might be brake reach, as there isn't much vertical adjustability with the Dia-Compe cantis that are on my bike (maybe yours has different brakes?)............And actually, in just re-reading your post, you wouldn't even need to go to a 130mm hub to go to a seven speed, just pick up a seven speed freewheel and thread it on to your 27's and you're good to go. Might take a little tweaking with the spacing, but it should be very close. There's a seller on ebay that regularly sells beautiful Suntour 7 speed freewheels NOS. Good luck-

edit: Here's a link to a nice page on Sheldon's site that shows catalog pages from Centurion's '84 model lineup, including the Pro Tour. At the bottom of the page there's sheet you can click on that shows detailed specs on the models, including the Pro Tour www.sheldonbrown.com/centurion1984/index.html I notice the whole lineup used Suzue hubs of one type or another in '84-

So... you have 126 mm spacing in your dropouts, and want to use a wheel spaced 130 mm, right?

No problem! :) Since your frame is steel, you have TWO choices:
* Just squeeze the dropouts open a little extra when you take the wheel in and out. This takes a few extra seconds, but unless you do a lot of wheel changes, it's easy.
* You can cold set the rear dropouts to 130 mm. This means PERMANENTLY bending them outwards. This is perfectly safe, but ONLY for a steel frame. Sheldon Brown's site has a good article on how to do it properly.

As well biked said, for a 7-speed hub your 126 mm spacing if fine. Either buy a 7-speed freewheel for your current wheel or find a 7-speed 700c freehub wheel (they are still available as are 7-speed cassettes). Try a 700c wheel on the frame first to be sure the rear brakes will also adjust properly.

The first thing that I would do would be to trial fit a 700c rear wheel to see if the rear brakes will adjust downward far enough. It might not be the same as the front.