Steel! Haha... There were many diffeeent types of steel from the basic carbon steels also known as mild steels to the alloys of steel, the most popular being chromium and molybdenum added to the steel which were known as chromeolly or cro-mo steels. Typical frame badges would have Tange cro-mo or Reynolds 500, or the heat treated Reynolds 501.
Going up from there you get manganese molybdenum steels... Which are badged under names like Reynolds 531, 531ST, 531C, 531MTB, and Reynolds 653. There was also a Reynolds 753 but if you see a 753, don't bother as they have a sell by date where after a year or two the livelyness of the frame will go dead as the metal ages. Also if you see Reynolds 453, it is ordinary bog standard mild steel,,and they are actually rare as othet makes of frame tubes were cheaper then Reynolds, so why pay extra for bog standard tubes? Only once have I ever seen a bike displaying the 453 badge). 653 is rebadged 531C. C stands for competition which has very thin frame tubes built for racing ad time trialing frames, and has a weight limit of a max of 16 stone for the riders... ST stands for Super Tourist which has stronger frame tubes used for touring bikes, and the strongest was the 531 MTB for mountain bike use.
More modern trends are to eliminate lugs and weld directly... Which is an issue as the 531 ranges (And 653 which is 531C) need lugs as they are either silver soldered or brazed... More commonly brazed for strength. So a new alloy of steel was formed which can be welded directly so lugs were no longer needed, and it was designed to be a weldable version of 531. Unfortunately those who have tried them thought 531 to be superiour. These are badged up as Reynolds 631. Actually I have never tried one as yet, which is hard to believe! They also habe Reynolds 831 (Or was it 853?) which is 631 but with an internal octagonal shape to the tubes but the outside is round. The idea is these tubes are stiffer so in theory give better performance, and these are said to be on par with titanium frames in the way they ride.
However, all is not what it seems. Todays bicycle frames are designed to be stiff. To reduce flex... Which is essential if one has an aluminium alloy... As aluminium needs to be stiff to prevent rhw material from breaking... Carbon fibre also needs to be stiff where the load bearing areas especially around rhe bottom bracket areas, hence they use the larger but (In my view based on repairing and servicing many of the things) probelematic design of bottom bracket assemblies.
Now ordinary mild or carbon steel will absorb your energy when you pedal it every time it flexes in the bottom bracket area of the frame, hence why most of these frames are not that lively, and they are also generally heavy. Ok, no two ordinary steels are alike. Some badged as ordinary steel mzde in Bangladesh on Emmelle bikes back in the late 1990's were out performing better quality aluminium bicycles which were typically six times their price! Yet a few ordinary steel bikes I have ridden... I could almost walk faster! Well. Not quite that bad... But you get the idea!
Now I mentioned the issues with bottom bracket flex in a negative way... (Where modern trends are to add a thick downtube to stiffen the frame as much as possible).... but 531 manganese molybdenum frames have (If the frame builders are experienced and know their stuff and habe taken advantage of this) a spring back effect to the flex. Now done right... Boy does this work well! One of my touring bikes is an Orbit, and Orbit was a small manufacturer which rather did their own thing, and their bikes either worked well or did not at all. Now when I bought this Orbit secondhand, initially I was dissapointed. Its owner said it was a Dawes Super Galaxy which I habe a Galaxy and done a great many miles on over the years. The super bit just means it had more expensive parts. Bug this bike had an Orbit Gold Medal frame, as the Dawes frame had been involved in an accident, so the salvageable parts were built onto the Orbit frame.
Tje issue I initially had was I thought the frame was bent as it wasn't riding straight. I happened to read up about Orbit bicycles on the internet, and I found a key bit of information which sorted out my problem. Now I was trained in how to straighten bike frames so I was gojng to attempt to do this... However, I found out that Orbit, doing their own thing, made the bike to take an undished rear wheel which is very unusual for a bicycle of this type, and as Dawes which in those days were traditional and built some cracking bikes... (These days I think they have lost their edge).. Well Dawes, like everyone else built their rear wheels dished. So I had a dished rear wheel on a bike designed for an undished rear wheels... Umm. So spokekey at the ready and 15 minutes later and voilla... I had a nice and true undished rear wheel...
And so I took the bike for a ride... You know I mentioned about 531 apringback? Well, Orbit, with this frame managed to pull it off so well I was absolutely loveing the ride!
So what does springback do? The idea is to use the frame materials springing qualities to aid pedalling efficiency rather then reduce it. The frames are made with a small degree of bottom bracket flex in mind. When the cyclist pushes down on the pedal, the bottom bracket flexes away from the force applied on it in a horizontally directed flex, and this flex is held until the cyclist reaches the end of the pedal stroke. When the springiness of the frame material goes to return the frame back to its origional position, tjis spring back effect provides that little bit extra force on the forward momentum of the pedaling power so it carries the cyclists pedalling through the dead area of the pedalling stroke so the next stroke of the opposite pedal is ready to do its work... And the effect, when the frame has been built right is so awesome, that I wouldn't trade this bicycle (Or my other 531 framed bikes) in a direct swop for any of the modern bikes out there. And yes 531 is still available, but as they no longer make 531 chain and seat stays, you are only going to get a 531 mainframed bicycle, so it is doubtful you will ever get the springback quality to great effect like the older bikes had it.
So try to get an older 531 framed bicycle... Even if it needs a complete rebuild. Do not be tempted to open out the rear forks to cram any more then a 7 speed freewheel or cassette in it as though it can certainly be done, you will have altered the qualities of the springback effect... Just fit a triple chainset instead to increase the gear range...
So to conclude, steel frames are so varied... I could ride one of my 531 framed bicycles three times as far and at a much faster speed on the same energy that I would take to ride a poorly made standard steel heavy bicycle. It is all about how the frames make use of rhe pedalling efficiency... And ordinary carbon steels do not have the same spring back speed, so they tend to habe the sappinh effect of the movement of rhe bottom bracket area without the correct timing of the return of rhe movement, so the further hamper the efficiency of the bike, as the return movement is hampering the initial pedalling stroke of the opposite pedal... (Hence why the modern trends are for smaller frames with stiffer downtubes to keep the frames as stiff as possible. Yes the initial pedalling is more efficient, but one does not have the extra springback to help the pedalling motion through the dead section on the pedalling stroke...
21 Jun 2019, 8:20 pm
