531 Professional SL tubing

[oldgit]

Is it as weak as people say? the answer will have an effect on the final rebuild. Either a pretty to look at ride to the pub show off thing, or something for the odd decent ride.
And if I buy a set of clinchers to use instead of the tubulars.

 

[Midlife]

531 SL came out in the late 70's and was renamed 531 Pro in about 1982.................can't say I came across any "weak" frames BITD.

Being thinner the rear nightmare is rust which can be a nuisance for 531 but trash 531SL (and 753/ 753) Especially around the BB.

Shaun

 

[daccordimark]

It did have a reputation for denting easily because it was thin walled tubing like 753 but not heat treated.
I was always careful to make sure the 'bars didn't swing round and hit the top tube because of it.
My 531SL frame seemed strong enough to me.

Mark.

 

[roadking]

Re:

They can be dented (esp the top tube as Mark suggests) if you're careless. I've four frames in these tubesets (3 x SL, 1 x Pro) and not had any problems - and they're always stored with pipe insulation on the toptubes -saves accidental paint damage as well as dent prevention.

Rk.

 

[hamster]

Also, 531 fork blades were on the heavy side, so in a crash the impact was transferred to the frame, folding up the down tube rather than the fork.

Later tubesets had lighter fork blades which tended to bend before the frame.

 

[oldgit]

This is pretty rusty. The forks are Professional as well and have cut out crowns with alloy inserts.
I've had it indoors for over a year and really must sort it.

 

[oldgit]

 

[gavr]

Re:

While 531Pro replaced 531SL the Pro and SL tubesets are not the same. I always thought 531Pro had 753 seat stays and the thinner 531 un-heattreated main tubes. Pro is closer to the later morph to 653.

I stand to be corrected of course...

 

[Midlife]

gavr, you may well be right. I just made the naive assumption that when the 531SL sticker went and the 531Pro sticker arrived they had simply rebranded the product for some reason. I never thought much about it.

Rather like Marathon morphing into Snickers and Opal Fruits into Starburst LOL

Shaun

 

[roadking]

Re: Re:

While 531Pro replaced 531SL the Pro and SL tubesets are not the same. I always thought 531Pro had 753 seat stays and the thinner 531 un-heattreated main tubes. Pro is closer to the later morph to 653. I stand to be corrected of course...

I don't wish to be churlish gavr but you're confusing the 531 Professional tubeset with 653; this subject has been posted many times on RB.

SL was replaced by Pro, and they were really the same tubesets. 653 then replaced Pro in 1986, 653 was referred to as (at the time) a concept tubeset - a mix of 531 and 753.

Framebuilders with enough prestige (say riders with Professional - Tour of Britain wins or outstanding amateurs) could specify non catalogued tubesets from Reynolds. I have a frame made in 1964 from what is essentially 531SL, many years before it was commercially available.

Rk.

P.S surprised Midlife doesn't remember this - early onset Shaun?