531 double butted cold setting limit

[sawston_vulcan]

I put my Ron Cooper frame in to be painted at Colourtech in Dartford years back. It was 126mm spacing and I had some nice mavic wheels with the correct spacing that I planned to use.

When I dropped the frame in I got a nice surprise, in a small workshop at one end of the building Ron Cooper was there and still building frames.

So I asked him to fit a second set of bottle mounts which he duly obliged.

When I got the frame home I was quite puzzled as to why my nice mavic wheels didn't fit properly.

Turned out Ron had re-spaced the rear end for me and didn't mention it..... Fun times and a pleasure meeting the man himself

But I guess what I'm saying is that Winston Vaz will have the skills to re-space that Roberts frame

I opted out of buying the Roberts frameset and have bought a Bob Jackson 531SL frameset that has been cold set from 126mm to 130mm!

 

[hamster]

I could but all my kit is 10 speed!

Remember that you can run 9 from 10 on a 7s hub - as it's a TT frame, just discard the largest sprocket and spacer.

 

[frkl]

There were a number of suggestions about respacing a 130 hub to 126, and I started thinking about doing that for a bike in which been using a 130mm wheel without setting the 126 frame.

Does anyone have good sources for getting the 126 axle? is it something that can be purchased new, or does one have to find 126 hubs?

 

[Canuk]

Any axle will do (ideally it should be longer than 150mm. The video from YouTube up thread is pretty conclusive about how to do it.

 

[frkl]

I see videos about respacing frames in the thread, but not about axles and hubs. I have done this bringing a 130 to 135, so as to bring a road hub onto a mountain bike, but not reducing the spacing. So technically not an issue, just wondering about recommendations for the part itself.

 

[Guinessisgoodforyou]

There were a number of suggestions about respacing a 130 hub to 126, and I started thinking about doing that for a bike in which been using a 130mm wheel without setting the 126 frame.

Does anyone have good sources for getting the 126 axle? is it something that can be purchased new, or does one have to find 126 hubs?

You can cut down any axle. Dress the cut end with a file and deburr the qr hole. Most 126mm axles will need to be 135mm length to make sure you have enough in the drop out, assuming forged drop outs and quick release. SJS cycles or Spa cycles for spares.

 

[bulgie]

I opted out of buying the Roberts frameset and have bought a Bob Jackson 531SL frameset that has been cold set from 126mm to 130mm!

Uh oh, 531 SL chainstays have a poor track record for durability even when not cold-set wider.
The first batch of 531SL stays were particularly bad, those are the ones where the tire clearance is a sort of flattened area on each stay, the ends at a sharp-ish transition. A lot of those broke, right at that sharp transition.

Later 531 SL c-stays came with the more copacetic Round-Oval-Round shape, and were more reliable.

Tha bad shape is hard to show in pictures, but here are a few I've found:





Not all of them broke! I wish a long life of many happy miles for you and your bike. fingers crossed

 

[Canuk]

I saw the same thing on a bike I lusted after as a teenager. The posh kid in our club (his old man was a used car dealer/would be gangster) turned up one day with a Raleigh 753 'Service Course' TT bike. One of the very first ones in the retail chain in champagne gold.

He decked it on a wet roundabout in his first time trial and cracked the tube right where you have indicated. I'm not sure but I think the stays and forks of early 753s were 531 SL, and that was it. Buggered.

He tried in vain to get a replacement from Raleigh, but I don't think it ever happened. I've never seen anyone so wholeheartedly gutted over a bike!

 

[sawston_vulcan]

Uh oh, 531 SL chainstays have a poor track record for durability even when not cold-set wider.
The first batch of 531SL stays were particularly bad, those are the ones where the tire clearance is a sort of flattened area on each stay, the ends at a sharp-ish transition. A lot of those broke, right at that sharp transition.

Later 531 SL c-stays came with the more copacetic Round-Oval-Round shape, and were more reliable.

Tha bad shape is hard to show in pictures, but here are a few I've found:

View attachment 919694
View attachment 919696
View attachment 919697

Not all of them broke! I wish a long life of many happy miles for you and your bike. fingers crossed

Is the same true of 531 Professional tubing or had problem been solved by then?

 

[bikeworkshop]

I think it's a risk with a high quality tube, the stress-riser at the Chainstay bridge, coupled with a little too much heat when the joint is brazed.
Maybe later they left a little more wall thickness at this point?

I've seen quite a few quality steel frames snap clean through at the butt