Wildwood 

I have only a few data points, and also only my touch points to prove me accurate.

61 cm all SLX with light internally lugged sloping crown fork.
62 cm R531 db f+f.

Not saying that it's a better or faster ride.
Not discounting drivetrain stiffness as a good thing.
Not against mixing tubesets for size and ride tuning.
But all tubes thin means 'Cloud-like' rides. even with 22mm tires.

yeah, yeah... geometry makes a big diff. But 73deg parallel seems a good common point of beginning, for discussion purposes.

ANYONE ELSE AGREE?
YMMV


will update with pics.

It only makes sense, a tube that's longer and a rider that's bigger makes for a more compliant ride.

Wildwood 

Classtime 

Yes. Yes. But I would say don't go any further or you hide too much seat post for a classic look and from my experience, an excessively long head tube makes the front of a thin tubed frame too flexy when I need to push and pull on the bars during hard efforts. Of course some flex comes with vintage stems and bars. I recently sold a tall one for those two reasons and just replaced it with the same model only shorter. We'll see.

RiddleOfSteel

Welcome to the brotherhood, my friend. May your SLX and 531 find a friend alongside Tange Prestige, SL, and others.

63.5cm, 64cm, and 66cm frames graced with wonderfully thin Prestige tubing reside in my stable. Whippy? Eh, they certainly flex one way before springing back the other. The man-and-machine dance is one to experience and enjoy. One would think 66cm of the lightest tubing I've weighed (as a frame/fork/headset combo) would result in an overly-noodly riding experience, but it is a giant-killer. It is also a road vibration muter, setting itself somewhere in between great steel (with a B17 saddle and nice tires) and modern carbon fiber. I am of course talking about the Land Shark. My 64cm Davidson Impulse lights up a climb or acceleration as good as anything else made, and my 63.5cm Prologue guides you through a many a mile without demand.

I will say, though, a de-tuned wheelset (or just spoke tension) do a lot for ride feel. A stiffer and nearly new ho-hum wheelset with 35mm tires on my Paramount makes that bike immensely responsive out of the saddle. A classic MA2 to 7400 hubs wheelset with spokes that need a bit of re-tensioning makes that same Paramount (with "33mm" tires that measure 28/29mm) incredibly compliant. Those same wheels and tires made my '81 Trek 716 mushy.

Man, between the beer and this thread, I'm going to have a hard time trying to still sell some of these last few bikes....

Drillium Dude 

How would you characterize the Atlanta 1996 wheelset? I had one back in the late 90s and remember them as needlessly heavy (seemed the extra material only served to form the aero profile), they spun up slowly and took a lot of effort to keep up to speed. They were, however, next to bulletproof and survived a couple crashes without ever going out of true.

Another drawback I recall was finding tubes with a valve stem longer than 35mm. That's common today, but back then you had to buy these alloy valve stem extenders that sometimes worked and sometimes snapped the top of the valve right off the tube if you weren't careful.

DD

Insidious C. 

I reluctantly agree with Wildwood on larger frames feeling smoother as a general rule. Reluctantly, because I am self concious about beeing seen riding "French fit." Fortunately for me there seem to be exceptions.

RiddleOfSteel

Besides being the absolute worst thing to mount tires to, with these 6400-era Shimano 600 hubs, these things roll. And effortlessly so, right from the push-off from a stop. I have not felt them slow to spin up. Out of saddle efforts in accelerating or climbing have never felt labored. Now, I'm a tall guy and 210-ish lb, so the extra mass and 175mm crank length certainly helps me. The flywheel effect + parabolic profile makes for easy speed keeping as far as I've run them. I need more miles on them, though. My longest stint has been 25-30 miles, with half of those with a quickly worsening ilio-tibial band etc. But I've had good 10-mile stints where I whipped up some proper speed on an all out sprint effort. They hardly even affected the magic carpet ride quality of the Land Shark frame when I switched from wheelset that was literally a pound lighter. As little wear/use as they'd seen prior to my ownership, I've gone through the hubs, cleaned/polished the wheels, and trued the rims (one spoke became rattly loose) while checking all the spokes. It's good to go now for sure.

sumgy

"Only" 58cm and made of PRX (which is apparently heavier, and so I am guessing thicker walled than SLX).
It is the smoothest riding frame I have ever ridden (even compared to my Ti Moots).

thinktubes 

Don't forget fatter. My frames seem to move better in the spring when I'm still packing the "winter 10".

Wildwood 

My 58cm frames of SL, R531 (all tubes, including fork blades) seem stiffer, and handle quicker, than 62s.

But this is a comparison with only 'touch point facts'.

rando_couche

IME, anything heavier than 531C in a 62-66cm frame feels harsh and "dead". Probably the worst in this regard was my 65cm Eisentraut Limited touring frame. Admittedly, it was optimized for loaded touring (HEAVY tubing) and I was using it as a rain/rando/training bike, but it always felt as if it was actively resisting any effort on my part. A shame, because the geometry and metalwork were wonderful. Just couldn't stand to ride it. I'd love to try a 753/531P/Columbus EL bike in my size some day.

SP
Nwpt, OR

Barrettscv 

Even my 64cm Serotta Nova Special X with heavier Columbus SPX tubing rides very plush. My 64cm Peugeot PX10 with metric Reynolds 531 is very plush and a little too flexy.

John E

The only objectionably flexy frame I have owned was my 1960 Capo Modell Campagnolo. Unlike my current 1959, it had double-butted 531. With a Pletscher rack loaded with textbooks, it was not the ideal university commuter, particularly on climbs, when the BB swayed in the wind, or descents, when it oscillated. In contrast, my lowly UO-8, albeit one frame size smaller, is a superb workhorse. I suspect the panniers help, since I no longer pile cargo on top of the Pletscher rack, but it still seems better suited to being a beast of burden.

squirtdad

I think this may be mostly the case, but tires and wheels can make a big difference......and plush is not all there is

so my recent experiences,

90/91 De Rosa 61cm SLX ultegra 6800 hubs, mavic open pro, Vitorria corsa g+ clinchers 28mm, brooks swift saddle Frame is really too big (and has been moved on) basically almost no seatpost showing very smooth ride, stable

84 Team miyata 56 cm (smallest fit for me) Miyata DB tubing, dura ace hubs, Mavic MA40 rims, bontrager 25 mm tires (feel skinny for 25), flyte titanium saddle..... didn't put many miles on as a new wheelset was coming.....handling good, ride harsh, bumpy

84 Team miyata 56 CM (smallest fit for me) Miyata DB tubing, sanshin hubs, mavic 330 rims (wheelsmith build), Challenge Elite pro tubular 25 , flyte titanium saddle..... OMG a magic ride, not plush but smooth, sucks up bumps, super lively, wants to do corners even my jaded mechanic could not believe it

85 Team Miyata 58 cm (my sweet fit) Miyata triple butted tubing (but not splined) ultegra 6800 hubs, mavic open pro, Vitorria corsa g+ clinchers 28mm, brooks swift saddle ride is smoother than the de rosa, lively, sucks up bumps not quite the OMG of the 84 but close

So my conclusions frames can make a big difference, sizing matters, and wheels and tires can make huge differences. bottom line for me no single formula, appreciate the difference and keep trying new combos

USAZorro

Even when I had horrid, cheap 23mm tubular tires on it, my plushest riding bike is my 1972 Fuji Finest. I believe it has Ishiwata butted, or double butted tubing, and the frame size is a 56. With 26mm Grand Bois Cerfs on it, I would routinely cost down hills faster than almost anyone on the club ride on this bike (even the heavy guy with the expensive Rolf hubs).

My other "plush" riding bikes have rides that I think are as much attributable to their high volume tires as anything else. They are mostly Raleighs with 21-1/2" frames. The tubing on them is all Reynolds, and either straight gauge or butted. However, one is my stupidly heavy converted Giant Iguana. It does make some intuitive sense that frames with thinner gauges with longer spans will be "less stiff", and therefore, "more plush", but I think it's more complex than that.

Kabuki12

All my bikes that I ride regularly are 25" frames and all feel nice and comfortable. My ItalVega and my Windsor Pro are both Columbus tubed frames and feel a bit stiffer than my Raleigh Competition GS and my Super Mondia which are Reynolds 531. Interestingly enough the Raleigh is the only bike in rotation that is a 23" frame. The Windsor has straight gage spokes while the others are double butted spokes(more flex?) The chain stays on the Windsor are quite a bit beefier than my other bikes , being a Cinelli copy. If I had to pick a favorite , it would be hard to do. I also have my first racer I ever bought which is my Kabuki Diamond Formula(25") which is plain gage 4130(who knows?) . I love that bike for sentimental reasons, but when mashing up a hill I can feel quite a bit of flex! I guess this is why we NEED more than one bike? Joe

Paul J

My big bikes are SP and SPX, being a big guy, over 200 I'm happy with the ride quality. My most flexible bike ever was an early Alan screwed and glued which if I was riding smooth was great but man would it fight back and going down a hill watching that aluminum fork flex was a little scary. :-)

ascherer 

Relativity exercise: both of these frames are 62cm. The Mercian is 531c, the International 531. Their geometry is quite different. The Mercian is more upright - 74 degrees parallel, with shorter wheelbase, stays, top tube and rake than the Raleigh. It also has Mercian's distinctive reinforced bottom bracket shell for extra stiffness. It runs with narrow, supple Michelin Pro 4 Comp tires and the International has Compass Bon Jon Pass tires.I'm very comfortable on both. I would say the International is plush. If I know I'll be riding on irregular road surfaces for a long while, I'll prefer the International. The Mercian is solid. It's fast and very quick handling but never harsh. I couldn't say it's plush, but I'm happy to be on it all day long, and it runs smoothly on rougher rural pavement, even with the narrow high-pressure tires. No question that I prefer the ride and handling of my Mercian, possibly because I've had it for 31 years now and the International only 3.

easyupbug 

Even at 58 ctc st and my tt 57 or 58 I would agree. I have a lot of data points over the 60+ years in saddles. Today's daily riders are SLX, SL, EL, MS, 753, 853, Prestige, Gilco. In the last year a late model Vitus 979 frame from a forum member has been getting time and I love the ride, which is a surprise as I think early aluminums loosened fillings and I have replaced an aluminum fork on a Specialized Allez Pro trying both steel then carbon, both for an improvement.

Mr. 66

I have to admit that this summer I picked up some fantastic 61ish this summer that float my boat, one that has found a higher calling. A Univega Gran Premio 61cm which I feel rides very comparable to the Miyata Team/Pro 58cm, but the feel I had of those two the Miyata had just a tad more flex.

SurferRosa

I assume Reynolds started using 531c to denote full 531 (with db main tubes). So the tubing thickness of the two bikes should be very similar.

ascherer 

I’ve read that 531c became the name for what had been 531.

gomango

Can't miss with Columbus EL-OS.

My John Hollands Sportif is soooo nice.

The tt is 58cm and the st is 59 cm.

A smidge big, but I get by with seatpost/saddle/pedal adjustments.

Pretty as well.

Road Fan

According to Touring Bicycles by Tony Oliver, 531 Competition is (TT, DT, ST) 8/5 db, 9/6 db, 8/5 sb. To compare, Columbus SL and SLX are 9/6 db, 9/6 db, and 9/6 sb.

In his text he vaguely references a tube set that I think is the one Trek used at least on the 6xx frames: 531 CS: 8/5 db, 10/7 db, 8/5 sb (numbers from the 1982 brochure on Vintage Trek Bikes- Information on Steel Road Bicycles made by the Trek Bicycle Corporation, bike). I think he said it was called "Club Sport," though I'm not sure that corresponds to other site info that is out there.

There was also a 531 Professional, which was 531 alloy with the butting profiles of the lighter 753 tubes.

seypat

Hard to say since tall people can't be fitted properly to small frames and visa versa. Plus, the frame geometries are different. There is no way I could ride a bike with a short TT in relation to the rest of the frame. Luckily, I ride 54-56 frames. I can go 52 or 58 as well. 52 means a really long stem and seatpost. 58 means the saddle is about touching the frame. The key for me is a 55-56ish TT. It will work with that. I weight around 200lbs. Probably as heavy as most of the bigger riders on the forums.

The stiffest frame I have is a 52cm 90/91 Team Miyata. That frame is way stiffer than the 50cm Lotus Unique I have or the rest of my bikes.(the Miyata and Lotus are for the rest of the family)