Bob Jackson 531c project

No need to cold-set from 126mm to 130mm: as Matisse said, it'll flex. Getting the wheel in and out will be a little bit of a faff, but over time you'll find it eases as the frame resets itself.

But if you do cold-set, then do something along the lines of Sheldon Brown's method. The threaded-bar-twixt-the-ends method isn't reliable: you're bracing one side against the other (rather than a static point) and small variations in materials and construction mean that one side will move more readily than the other.

Arrived today, and rode home wearing it! I'll be taking the mudguard eyes off it, before sending it to Mr Jackson for a bit of tarting up!

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Got full pics of the whole frame?
Does it really need a respray? Looks nicely aged.

Oops, sorry. I did upload 5 photos, but looks like only one came out!

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Another

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And again

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One more then

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Kurust to block further rusting where paint is missing, careful touch up paint on top, save a respray, keep the nice patina? Haven't seen the frame in the flesh obviously.

Otherwise, I think Mario Vaz would do a good job on a classic frame like this.

TBH, it's pretty ropey all over. The decals are not original either, the frame being too old for that style I think.
I have something very nice in mind

Mike

Why would you take off the eyelets? Mudguards are the best.

I don't do mudguards

That's what I thought too. Until I bought mudguards. Best bike purchase ever. Seems a shame to unnecessarily remove the option for them.

That's what I thought too. Until I bought good mudguards

This

Gone now I'm afraid, odd to have it built with guard bosses but no bottle cage bosses though. No signs of clip on ones either.

Not sure of the year, I may get in touch with the factory to find out.

I had my eye on this! Already got a frame having a respray though so couldn't justify it. Looked almost like the black paint on the head tube in the original post photos was painted on like acrylic, looked very matt. Any particular reason you didn't just leave the bosses and not attach mudguards, just curious? Yeah as many have said 531C is for the Competition edition of 531 tubing. I always thought it was lighter than the standard double butted 531 but I think its actually a rebranded version of it. They used to have 531SL (Special Lightweight) which had thinner wall thickness but was only round for a really short time before it became 531P (Professional). As this changed its name I think that they also changed standard 531 to 531C. Chart here for weight comparison and another for tubing specs:

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Thanks for the info, I'll have a look when I start up the computer.
Just don't like the look of a frame with the eyelets, and as I won't be using guards either, I cut them off. Yes, the paint is a curious one. Not sure when the newer font came out for the decals, I wonder if it's been resprayed at some point, using them.

I hope this is a bike for life.

Interesting looking frame this and it will be good to see what info JRJ say about it.

Its got hints of an early frame about it, guides, seat clamp and the lack of bottle bossess, but then some of the lugs and the fork crown scream a later date.

Also if you follow the JRJ numbering you can find on t'internet, the serial number seems to put it about mid to late 80's and even 90's, maybe. Also Didn't 531DB, become 531C in, or around 1981, I seem to remember reading this somewhere, but cant find it now.

I have a similar frame, and it turned out that it was a 50's TT frame, re worked in the 70's and used for TT training, hence no bottle bosses but eyelets. Odd Yorkshire testers.....

Meaning what? Can you elaborate on that?

I may look into that a bit more. May change the type of build I had in mind. Donald ( BJ Cycles didn't answer that question earlier )

Mike

Apparently, they used to provide you with a small card showing tubeset, all the build info and dates etc, if you requested it, but you had to pay for it! Between £10 and £25 as well.

Don't know if they still do that though, must have had to hold a lot of info about previous builds.

I just e-mailed them about it. See what they come back with. I am giving them some work, so they may help out for free. Maybe.

Mike

Just the standard wind-up. It's a shame to cut the mudguard mounts off, as if you sell it, you have removed the opportunity for someone to mount a proper set of mudguards in the future. So therefore the hope is you don't sell it, it is a bike for life, and you can forever revel in the lack of a dry bottom.

Oh fair enough.
Presumably someone could have the braze ons put back on, were that the case? Not that it will leave me intact!
Trying to find out age, then I'll make a final decision on what colour to go for, along with groupset.

Mike