bikemig 

Nah you can set it if its Reynolds. From 1970 to '73, the rear triangle was not Reynolds per the catalogs but I don't know whether it is hi tensile steel or not. It would not surprise me if it were though. If it is, then you will find it easy to spread the rear triangle. I think the '74 is also not full Reynolds. The catalog is not as clear as it could be on this but there is a poster here with a '74 and the sticker was Reynolds 531 main frame and fork.

https://www.velo-pages.com/main.php?g2_itemId=33193

Does your bike still have the Reynolds sticker? A pic would help here.

If you have all the original stuff, I'd be tempted to do a resto mod.

TullySteve

Unfortunately almost all the decals are gone, including the Reynolds sticker. There are just a few artifacts on the downtube, and the headtube sticker (not a physical badge) is still intact. I do not still have the Campy rear der (I had swapped it out for a Suntour with a wider range cluster for hilly riding and touring with panniers. I think I know where it is in my old barn unless the new owners really cleaned out!) or the Brooks saddle, or that original gear cluster. When it was in better shape 20 years ago I looked into resto and was not encouraged about its value due to not being "top of the line", and with kids & such that was the end of that. I'm more interested in using it for my riding style now, not a restoration. At the risk of being asked to leave this forum thread LOL.

bikemig 

The important thing is that it is your bike and you know what kind of riding you do so get it on the road. I'm suggesting that 2 x 7 gearing, 126 OLD wheels, and a crank you can run smaller rings on (say a Stronglight 99) may do the job for you as well.

ZudeJammer

Baby steps with the SB method of leveraging of the frame or you will overbend, I went back and forth a bunch taking a 531 frame from 110 to 130 because I was not patient enough. Luckily the frame rides great so overbending a tiny bit shouldn't matter. (used the RJ diy tool method of alighting the dropouts too)

gearbasher

I slightly over bent one frame was able to bend it back with fairly light pressure using only my hands. It was like the frame wanted to go back.

scarlson 

They're always easier to push together than they are to spread apart. Just my experience. And 531 will be harder, but you can do it just fine. Just helps to know what to expect.

Going out now to ride on my Ron Cooper, spread from 126 to 135 and I've done 6 months of loaded touring since then.

TullySteve

Well I was successful using the threaded rod through the dropouts method. I took a few days just nudging it along. I think I went out to around 165 before it came back to 130. Using a string (no other tools available here), the frame appears to be fairly symmetrical. Now I need to align the dropouts.

Doug Fattic 

Let me suggest a DIY method that is superior to the string method. Perhaps you can get an inexpensive 4 foot aluminum level - the kind that are sold in places like Lowes and Home Depot. You can do a lot more with a level (or any straight piece of metal) than you can with string. Unfortunately the inferior string method is always mentioned when the subject of DIY alignment comes up.

Your 1st goal is to see if either your seat or down tube are leaning over to one side or the other. It can help if you have your bottom bracket cups without the axle screwed into your bottom bracket shell. These can be a truer data point than the face of your BB shell. Your level placed against these cups can allow you to measure any alignment discrepancies. A clamp to hold the level against the cup along side the seat tube can be helpful if you don't have 3 hands. Measure the distance from the level to the seat tube close to the BB shell. Now measure the distance of the seat tube up by the seat lug. Of course they should agree. If not then you should bend the seat tube until it is straight up. This alignment is important if your shoes are cleated into pedals to avoid aggravating your knees. If you can't do this then don't bother with a string method because that system only works (barely) if the front triangle is aligned. After bending the seat tube straight, now check the down tube the same way. Start with a measurement near the BB and then up by the head tube. Bend as necessary. Now you are ready to check the rear triangle.

Place your 4' level against the head tube and seat tube. It is best if your level is as close as possible to the down tube but not of course on a lug. Now measure the distance from the edge of the level to the inside face of the dropout. Flip the level to the other side and measure again. Of course they should agree or bend the chain stays until the dropouts are the same distance from the level as well as being whatever distance you require. 130mm?

There are various methods to check if your head tube is twisted including sighting along the head and seat tube to see if they look parallel. If you have a flat surface, you can try to get a 4 point touch with 4 blocks under the ends of both the seat and head tube.

It is possible to make your level a more useful alignment tool by taping a M5 hole at one end and using the bolt as a distance tool instead of a small ruler held against the level (to solve the problem of not having 3 hands available). The bolt can be improved by sharpening the end to a rounded point.

If all of this seem like too much, than of course you should take it to a frame builder that has all the right equipment and knowledge to do the job properly. The fork in particular can be very difficult to check the alignment without fixtures.

ThermionicScott 

I've used the string method thus far, but good stuff for next time I have to check alignment/adjust spacing. Thanks Doug Fattic !