7 Speed Wheel 5 Speed Cassette?

a) Unless you really love that old bike, consider just getting a new one before spending money on this one...even if it's a similar bike from craigslist.

b) Your old 5spd is most likely 120mm spacing if it's from the 70s...if it's a little older, it could be 120 or 126. The new wheel is the now-standard 130mm spacing. This means that you can't just directly swap wheels. However, with steel frames it's pretty simple for a competent bike shop with frame tools to spread your stays a bit wider. They need to do it right so that the bike will track properly, but it's safe with steel frames so long as you don't have excessive internal rust damage. The shop may do that fairly cheaply...a mechanic familiar with the tools/technique can take care of this in a half hour or less.

c) If you go ahead and spread the frame and buy new wheels, you might as well select a different wheelset that uses the more modern freehub/cassette design rather than the finicky old freewheels. You can find a low end pair for around $60-$90. Finding a 27" pair might be a little more challenging, but they're still available. 700c is the standard wheel size now (just a touch smaller than 27") and if you put those on your bike you'll need to be sure that the brake bads will adjust low enough to reach the new, smaller rim.

You also have the option to hunt down the proper wheel that will be a direct fit for your bike/frame as is, of course. Again, harder to find sometimes, but any bike shop can order one for you. You might also be able to drum up a free or ultra cheap wheel via a bike shop, thrift store, craigslist, garage sales, etc. There are still lots of old bikes and many of them get unloaded for $10-$25, so if the wheel fits that's a great fix if you're patient in locating something.

good question

issue is the frame spacing

this one says it is 130mm OLD

what is a 5 speed?

120 mm Rear 5-speed,

read this

http://sheldonbrown.com/frame-spacing.html

no it won;t work

if you want to risk ruining your frame by spreading it out 10 mm, read that

http://sheldonbrown.com/frame-spacing.html

also it isn;t a cassette

it is a freehub

anything that is a real cassette, also won;t work

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Some standard spacings:

91 mm Low-end front hubs.

96 mm Older front hubs, especially French.

100 mm Modern front hubs.

110 mm Rear older track, coaster brake and other single-speed hubs. Also, front hubs for Downhill bikes with 20 mm axles.

114 mm Rear 3-4-speed .

120 mm Rear 5-speed, Ultra 6, newer track hubs. <<<---you

126 mm Rear 6- and 7-speed (road); some newer internal-gear hubs.

130 mm Rear 7-speed (MTB) and 8- 9- and 10-speed (road); some newer internal-gear hubs. <<<--what yuo want to buy

135 mm Rear 7- 8- and 9-speed (MTB); many newer internal-gear hubs.

140 mm Rear tandem.

145 mm Rear tandem (newer models.)

150 mm Retro-Choppers, some Downhill and Freeride models.

160 mm Rear tandem (new Santana proposed standard.)

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actually it doesnt; make sense

measure your OLD

if it seems like 130mm would work then go for it

if the frame is too wide you can add spacers

problem comes if the frame is too narrow

question is can you spread it out and not ruin it

or maybe jjust get the right wheel?:)

wle

I'm guessing you have a freewheel, not cassette. You are off 10 mm. I'd just

get a good rim and relace the rear, relace is $50 or so as long as the hubs mechanics are fine.

The front, you can buy a premade wheel.

Sounds like a good excuse to buy a new road bike.