Steel SS frameset recommendations?
 

I built up a Cross-Check as a single-speed gravel bike recently and I’m enjoying the single-speed thing a lot more than I expected. Looking for a steel frameset to build up as a city/road bike. What’s the most supple, cushy, comfy steel single-speed-appropriate frameset out there under ~$1000 USD? (Preferably quite a bit under, because I’m in Canada, and shipping/import costs if I have to bring it in from out of country can add up to 50%.) Considering the Wabi Special (I like lugs), Pake Rum Runner, Bassi Bloomfield, or a State 4130. Vintage isn’t really an option, there’s nothing much local and I need something in the 58-62cm size. Looking for something that'll really eat up the vibrations from crappy pavement.

Wabi seems to have the best reviews. I have never ridden one though. I do ride a '80's steel track bike on the rode and it is a rough ride.

SS conversions
 

The best I've found for steelframe ss/fg conversions are 70s 'bike boom' roadbikes. The 'suicide levers' are the giveaway afa as the vintage. They were made with relaxed geometry to accommodate the broadest spectrum of riders. With some the forks have to be cold set as they're more narrow than today's standard. Anything from a 103 to a 110mm bb will keep a nice straight chain line. I always picked the Pac-Rim brands because they had 68 thread counts and would accommodate wider tires...up to 40mm in some cases. Fuji, Shogun, Nishiki, Raleigh, etc. all make good conversions. I'd stay away from track frames as their geometry is a little too aggressive for comfortable street use. There are a ton of YT vids about ss/fg conversions. Have fun. Cheers from New Zealand! 🇳🇿

This. Contrary to popular belief, whether a bike frame is "cushy" or not has almost nothing to do with the frame material and everything to do with how long the bike's wheelbase is. An aluminum bike with a long wheelbase will always have a more comfortable ride than an ultra-short-wheelbase steel track bike.

Of course, there's always a compromise. Long-wheelbase bikes are comfy to ride but a bit bland. Short-wheelbase bikes are more exciting to ride but harsh. Best is to figure out where you want to be on that continuum and look for bikes with that wheelbase.

Yes, wheelbase affects the ride, but also head tube angle. A shallower head tube angle will transmit less shock up the fork axially and will allow the fork to flex more. Bikes like the Wabi have both long wheelbases and shallow head tube angles.

The '80s Japanese bikes were often designed around 27" wheels. Put 700c's on and you have room for big tires and fenders. I've used a Japanese built Schwinn, a Sekine, a Miyata 610 and now a US but very Japanese copy 4-something Trek as my city/rain/winter fix gears for the past 40 years. I've used Mafac Racers for brakes for both the reach and all-weather stopping power. (No, they are not discs. You have to use some awareness and foresight. But they will bring you to a stop on a steep descent in the wet.)

NJS frames
 

Japanese keirin steel frames are my jam. They can be equipped with brakes if that’s your preference.
There is a decent range of geometries within this category. Some are longer wheelbase, with relatively shallow frame angles (long and low) and as such have a comfortable smooth stable ride quality - predictable but unlike a lot of road bikes they don’t steer like a bus - some are steeper and shorter wheelbase and offer a more agile/nimble responsive ride - a bit closer to my Bianchi Pista Concept, which can be a real benefit in the right circumstance like negotiating city traffic.

That's the theory, anyway. I've never seen any measurements to support that belief; only "it stands to reason" and the like. Similar claims are often made regarding curved versus straight forks, and yet straight forks are as common as curved forks on performance bikes these days.

In the sixty years that I've been riding track and road bikes constructed of different materials and with different geometries, I've never been able to detect any difference in shock transmission that I can't attribute to wheelbase differences. In fact, it appears that head tube angles are chosen solely to achieve a desired wheelbase, with comfort being a consequence of the wheelbase choice, not the head tube angle. Lower average speed, more upright rider position: slacker head tube angle, longer wheelbase. And the reverse for higher average speed.

I disagree with the text that I’ve placed in bold. Head tube angle works in concert with fork offset (rake) to attain a certain amount of trail for different performance characteristics. Racing bikes require quicker steering than touring bikes, while still being stable at high speeds. As to my statement that head tube angle affects the shock absorbing qualities of forks, this is not a “belief”, but rather physical mechanics that can be quantified. The force that the wheel applies to the fork can be broken into two components as follows:

Axial component = Vertical force x SIN (head tube angle)
Transverse (perpendicular) component = Vertical force x COSINE (head tube angle)

As the head tube angle becomes slacker (smaller), the axial component of force becomes lower and the transverse component becomes higher. The axial stiffness of a fork leg is much higher than its flexural (bending) stiffness, such that axial shock force is transmitted with almost no attenuation, whereas transverse force is reduced far more as the fork flexes in bending.

As to straight vs curved forks, that is indeed an old wives tale, and there is no difference in shock absorbing qualities. I do disagree with your statement that straight forks are as common as curved forks on performance bikes these days. That may have been the case 20 years ago, but today straight forks are the norm, and curved forks are only seen on retro steel bikes like the Wabis.

welp polygon1
If you're buying new, and don't want to buy my 1980 Miyata OneThousand touring frameset (about a 56cm size-wize...), I'll point you to the Rivendell (aka RivBike) RoadUno.... if you can wait another 2 months or so... oy...
some info here: https://us7.campaign-archive.com/?u=...&id=a24d941b71

sizing, check out the Homer geometry: https://cdn.shopify.com/s/files/1/14...f?v=1706824082 (top row)

as for me, I'm going 58cm and purple.... but i can wait as i got too many bikes.
cheers!

Your calculations are based on the assumption that significant flexing of the fork does indeed occur. As I said, I'd love to see numbers from measurements.

Proponents of the idea that steel and titanium bike frames absorb road shock far better than aluminum frames make similar assumptions, but measurements of 1997 model year steel, titanium, and aluminum race bike frames showed that, for the chosen simulated rider weight (not specified, annoyingly), the vertical compliance of a Lightspeed titanium frame was 0.064" (and that of a Serotta Ti frame with "oversize" main tubes measured 0.054") whereas that of a Cannondale aluminum frame was 0.049", a difference of 0.015". Is such a difference perceptible, apart from tire and seatpost compliance (and, of course, confirmation bias)? I think not.

(I originally wrote that straight forks now dominate the market, but then I realized I haven't paid much attention to current designs for years, so I hedged my bet.)

My formulas do not make any assumptions regarding the amount of flex, only that there is more flex with a shallower head angle, all else being equal. Are your measurements based on a frame only, or a frameset which includes a fork ? Bicycles frames are basically trusses, where most of the vertical load is carried axially by the frame members and there is very little bending flex. So, even the most flexible frame is going to have a quite rigid ride. If you really want a soft compliant ride, you’ll get a lot more benefit from larger tires inflated to lower pressures. The only time you are aware of a frame’s flexibility is when you apply power to the pedals, which results in torsion and out of plane flexure of the frame members (mostly the downtube).

Here's another bike flexibility report from the 1990's, this one on fork lateral and longitudinal stiffness. For a given load (47.5 lbs), the measured amounts of longitudinal flexing of the forks ranged from 0.130" (for a very stiff Schwinn Paramount steel fork) to 0.185" (for a Trek carbon fork). So a difference of 0.055" from stiffest to most flexible. (The article notes that the Trek fork was something of an outlier compared to all the others.)

How one could use those figures to calculate the range of flexing of a given fork according to head tube angle, I don't know. I don't have the math skills. And I don't know whether it's safe to assume that the effect of head tube angle on fork movement is linear for differing loads.

You do apparently have the math skills, though, so if you can come up with some rough figures, I'd be grateful. My guess is that the effect is minimal, but that's just based on my own experiences, including the fact that my favorite race geometry bike has a straight fork built with oversized aluminum blades and a 1 1/8" steerer.

[Edit] Just realized that this is an unnecessary digression in this thread. Sorry!

oh man - sorry - i didn't pay good attention to your note after reading through the debate on bike geometry and materials.....

back to your question on cushiness - here's an alt-thought:
i think this Cinelli complete might be under $1k USD. https://usa.cinelli-milano.com/collections/tutto-plus
As a counter thought to 'cushy frame', this would allow cushy-tires (it's got canti posts and looks to clear a 700c X 44mm tire.

i understand the fattish tire can give an overly-dead feel to a pavement bike. I ride my cross-bike (lovely GUNNAR) on pavement quite a bit. Right now it's got 700c X 33.3333mm Jack Browns. These work find on pavement and dirt roads. I'll go fatter when I take off the fenders, soon.

take care and happy hunting.

Wabi Thunder will be most comfortable, but likely similar to the Cross-Check. The wheels on the Thunder feel more stable than the Classic wheels due to wider rims. The Classic / Special wheels are light, responsive and faster.

I think the Special will take 32c, that would be sweet.