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I am refurbishing an old 70s/80s bicycle, I have everything ready but the wheels, what set of wheels should I purchase that will fit this freewheel from Shimano?

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A bicycle of that era will likely need 27" wheels and 126mm rear spacing.

To confirm this, you could put a quick release or other straight small object through the dropouts (as if it were an axle) and measure the distance to the brake pads. A 27" is going to be around 630mm/2 = 315mm in radius to where the tire sits, so the brake pads should be able to extend a little bit closer to the dropouts than this (this is not exactly a way to determine what size wheels the frame was designed for, but just determine that they will work). Depending on exactly when it is from in that era and the quality of the bike, its possible that it would use 700c wheels (which have a very similar 622mm diameter) but very unlikely.

The spacing is the distance inside the dropouts:

enter image description here

from http://farm3.static.flickr.com/2061/1819835696_836e18f8ea_o.jpg

The rear should measure 126mm I would expect, and the front should almost certainly be 100mm (any wheelset that meets the specifications for the rear should also fit the front)

  • Thank you so much for the answer, I've measured and you are 100% correct, front wheel spacing is 100mm and back wheel is 126mm. And there are 315mm from the axle to the beginning of the brake pad. – Eduardo Sampaio Jan 25 '17 at 16:57
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    Great! feel free to mark the answer as accepted. If you need any more help making sure a wheelset will work, feel free to ask. – Paul Jan 25 '17 at 16:58
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    I am not especially familiar with EU shops as I am in the US. That wheel has a 3/8" bolt on axle, which will likely not fit in the dropouts of the frame that you have. You will most likely need a quick release wheelset that has a 10mm rear/9mm front axle. I found this rear wheel on amazon amazon.de/Wheel-Rear-Silver-126mm-WheelMaster/dp/B01KH33FGK/… but that price is insane. In the US we would sell that wheel with front wheel for around 120 USD. I would check with local bike shops first, it is a very common wheel. – Paul Jan 25 '17 at 17:12
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    it is possible that you could buy a 700c wheel and have it work, but you are attempting to do something the bike was not designed for so there are no guarantees. Also 700c wheels with 126mm spacing are extremely rare as very few bikes ever used that combination – Paul Jan 25 '17 at 17:13
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    The usual way to do it is you change the brakes to have ones with enough reach for a 700c rim, and stick a 700c wheel in (possibly spreading the frame). Velo Orange still sells 700c 126 mm wheels. – Batman Jan 26 '17 at 3:19
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Another option -- if you don't mind making the bike inauthentic -- is to change to 700c wheels with a 7-8-9 freewheel or cassette. Since you have a rear hub spacing of 126mm, it would require expanding the frame to fit a 135mm hub.

I did this with my 1975 Peugeot UO18 to turn it from a 2x5 into a 2x9 speed (actually 2x8, as the frame interferes with the smallest cog). Even losing the smallest cog, I expanded my rear cogs from 14-26 five speed to an effective 13-34 on the rear. Made going up hills so much easier!

Several caveats and thoughts:

  • As noted above, you will have to stretch your frame 9mm. Steel frames can accommodate this without issue.
  • Your brakes may not reach and you may need new brakes. My Weinmanns were just fine.
  • Your rear derailleur should might be fine as it is, if it is non-index, but you might need to replace it. Worst case is that you won't make the top and bottom gears, so your 9 speed becomes a 7 speed (see frame interference above).
  • You'll likely need a new chain, though
  • Going to 700c means wider availability of tires and tubes.
  • The 700c alloy wheelsets were much, much lighter than the old steel rims, so I lost about 2kg in weight.
  • A new wheelset means the flexibility of cassettes rather than having to use a freewheel
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    I'm actually surprised that your derailleur was OK. I've definitely had problems with this, as the pitch on a 11-34 is very different from a standard narrow 5/6sp freewheel and a lot of older derailleurs (mainly short cage) will run into the largest cog. Possibly remedied by slamming the B screw. Also, some deraillers just can't swing that far laterally to even reach all the gears, as they were only ever designed to work with 5/6 speeds and 7/8/9 is wider. That aside, this is definitely an option and does offer a lot of benefits (but is also more complicated). – Paul Jan 25 '17 at 21:38
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    an additional benefit: you can also often fit a wider tire in the frame as the wheel is slightly smaller and the tire sits where the chainstays/fork blades are slightly wider. I did a similar mod to my 1988 trek 520 to make it 3x8 with 700cx45mm tires. – Paul Jan 25 '17 at 21:43
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    @Paul - you're right, I did replace the original Simplex with a 1980s Campy derailleur. I can't remember if the Simplex had the reach for the top gear. I only needed enough swing to make 8 gears since frame interference ruled out the lowest cog. – RoboKaren Jan 25 '17 at 22:17

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