Those seat tube angles keep getting steeper

[bicycletricycle]

Seems like those seat tube angles keep getting steeper and steeper. What's going on here?

Ideas on ideal fit changing

The pursuit of ever shorter seat stays

Seats that provide more set back

More people using longer cranks

Need for super aero rear wheels that tuck into the seat tube

Lots of former multi sport riders buying road bikes

They aren't getting steeper and I'm crazy

People's feet are getting shorter


I can't think of anything else that could be a factor but I'm sure I'm missing something, anyone else have any pet theories? What's going on here?

[dave thompson]

More folks with shorter femurs (like me) cycling now?

[buldogge]

How steep are we talkin' Ryan???

-Mark in St. Louis

[rustychisel]

Yeah, nah, but nah. Think it reached it's apotheosis in the mid-late 1980s. Lots of 74.5º, bifurcated seat tubes, silliness like that.

What are you speaking of?

[benitosan1972]

Racing.
Wanting to race.
Wanting to look like a pro who races.

Racing on Strava. Slam that stem. Weight weenies. Aero Cervelo S5/Sworks Venge's.

Just look at how parts & accessories are changing too.
Deep carbon wheels, electronic shifting, race cut/fit, helmets with shields, etc

Bike Industry catering to Bike Dreams of looking, riding, living like a Pro? I'll have another espresso now, where's my Softshell jacket? It's getting chilly here.

[Dead Man]

Racing.

Racing on Strava.

Dude... Strava is the only reason I don't have credit cards maxed out like the rest of you bijez. Nobody can see your POS bike, just the time you post up.

I'm eagerly awaiting the days when people I don't otherwise know or ride with, but follow my profile, finally meet my bike. "You posted all those times with this?"

[rustychisel]

ok, but what's your seat tube angle?

[bicycletricycle]

just seems like i see lots of 73.5 + seat tube angles on bikes bigger than 58. im no expert on

bicycle fitting
bicycles
vintage bicycles
bicycle geometry
or
ergonomics

but.........

that seems a bit steep for me and in comparison to the historical norm.

did they get even steeper in the 80's? tesch's were steep, i remember those twin seat tube bikes but i didn't know they were steep, i thought they were just in pursuit of short.

[carpediemracing]

Those twin seat tube bikes with 36 or 37 cm chainstays were crazy steep, like 78 degrees. They also had really steep head tube angles, like 75 degrees or something nutty like that. Whatever green bikes the Wolfgang restaurant team rode in Tour du Pont when whoever went on a super long break (I want to say it was a sprinter guy that used to be on 7-Eleven, maybe like something McCarthy but not Mike who raced for Subaru?).

I think the historic seat tube angles were optimized for European riding, i.e. 150-180 mile stages in the 80s and before. There was a lot of resistance to any kind of change.

Then some folks (Guimard I think started it) did some biometric type experiments. Long cranks, aero > weight, etc, at least for Guimard's team.

Lemond showed up with his very long quads and wanted a really set back saddle position, hence his bikes' very shallow angle.

Then with triathlons riders started using really steep angles for the TT position. At first there were those forward reaching posts. Later the frames had a steep angle to begin with, making those crazy stem-like posts unnecessary.

At the same time some good riders had some issues forcing them to use a steep seat tube angle (Alexi Grewal started that).

Although riders like Davis Phinney went to a shallower angle for Europe he said that the steeper more forward position was better for US crit type stuff, anything where he wasn't riding 200km at a time or more. And, honestly, I so rarely ride even 100km at a time that it's a special day on my calendar when I hit the 100km mark.

Now riders will do what they think will work best, whether because they were in the wind tunnel or do a retul or whatever. Jens Voigt has an extremely forward position - he's either the same height as Boonen or taller but his saddle is much more forward.

Shorter femur riders (think Japanese as a general population, for example) need a steeper angle. My bike has a 75.5 deg STA. With 73 STA I was slamming my saddle forward on a zero set back post and sliding so far forward I'd sometimes slide down off the nose of the saddle. My quads are short enough that I always have plenty of legroom on planes or in the backseat of a car. When I visited Japan about 25 years ago I visited a custom frame builder's shop. His bikes were mainly 46-50 cm frames with typically 53-56 cm top tubes, designed for the Japanese riders in the area. Basically I would end up riding a similar frame. I took his frame for a spin, I think it was a 50x55, and it was great! I contemplated buying one but it was just too much money, I think the equivalent of $2k in 1985 or so. I maybe should have, in retrospect, but my thought process didn't work as well back then :)

I think that with the acceptance that not all riders need a 73 deg STA the bike industry (riders and manufacturers) have accepted that a steeper STA is okay.

[Lewis Moon]

Perhaps you're looking at frames from the Tri/Crit end of the spectrum? Since I've been back I've been pleasantly surprised at how many big frames have seat angles at or less than 72.5 and how many have "square" geometry. The last time I raced was back at the end of the short TT and steep SA* era. A dark time indeed...

[bicycletricycle]

thats interesting.....

i wonder how all of that seeps down into stock geometry.

do we have more short femured people? enough to effect the average?

since a very small amount of people actually race shouldn't geo be based on "comfort" (like the move to higher headtubes on many bikes) and not which type of theoretical racing situations we (I) will never find ourselves in, spring classics or downtown crit.

i know the knee over axle thing can be controversial, if the average cyclists body hasnt changes than we must be moving away from this slowly to knee in front of axle.

[polyhistoric]

I would also consider whether the increase in cross/gravel bikes have changed the balance of the rider over the bike, especially with increased rake to avoid toe-overlap.

Perhaps sloping top-tubes play a factor, along with the desire to use a set-back post for riders under 56cm sizing.

[oldpotatoe]

Perhaps you're looking at frames from the Tri/Crit end of the spectrum? Since I've been back I've been pleasantly surprised at how many big frames have seat angles at or less than 72.5 and how many have "square" geometry. The last time I raced was back at the end of the short TT and steep SA* era. A dark time indeed...

Saw two written interviews, one with Ugo DeRosa, one with Ernesto Colnago. Both said their stock geometry frames were 'ideal', in spite of them being on opposite ends of the spectrum. About 20 years ago. Looking at frames, most seem about the same as always. DeRosa pretty laid back, Colnago fairly steep, for say a 58....

[Lewis Moon]

Saw two written interviews, one with Ugo DeRosa, one with Ernesto Colnago. Both said their stock geometry frames were 'ideal', in spite of them being on opposite ends of the spectrum. About 20 years ago. Looking at frames, most seem about the same as always. DeRosa pretty laid back, Colnago fairly steep, for say a 58....

My last 'Nago ('93) had a 60 ST and a ~57 TT :eek:

[Kirk Pacenti]

thats interesting.....


since a very small amount of people actually race shouldn't geo be based on "comfort" (like the move to higher headtubes on many bikes) and not which type of theoretical racing situations we (I) will never find ourselves in, spring classics or downtown crit.



This is a real problem, but one that will likely never change. Like it or not, racing (or the fantasy it inspires in the customer) drives sales. Unfortunately, there might be 400 people in the world that can make a bike perform at it's limits as intended with racing geometry. The rest of us (no matter our fitness and how good our handling skills are) should probably be on very different bikes (imo).

In other words, we'd be giving up none of our meager 'performance' if the bike had slightly slacker angles, lower BB's, longer stays, higher bars, etc. But we *might* actually gain some performance from a more comfortable, stable and confidence inspiring ride. The Trek Domane (to me) is about an ideal bike for most enthusiasts and even it, could be a bit slacker and longer still...

Just because we all have a drivers license, doesn't mean we can go out and handle an F1 racer. ymmv.

Cheers,
KP

[zennmotion]

This is a real problem, but one that will likely never change. Like it or not, racing (or the fantasy it inspires in the customer) drives sales. Unfortunately, there might be 400 people in the world that can make a bike perform at it's limits as intended with racing geometry. The rest of us (no matter our fitness and how good our handling skills are) should probably be on very different bikes (imo).

In other words, we'd be giving up none of our meager 'performance' if the bike had slightly slacker angles, lower BB's, longer stays, higher bars, etc. But we *might* actually gain some performance from a more comfortable, stable and confidence inspiring ride. The Trek Domane (to me) is about an ideal bike for most enthusiasts and even it, could be a bit slacker and longer still...

Just because we all have a drivers license, doesn't mean we can go out and handle an F1 racer. ymmv.

Cheers,
KP

No, this is a mis-informed opinion based on what? Meaningless without pictures, we need some good illustrations of just how terrible and boring, for example, a welded steel bike can be, built just so we can "ride far", "efficient", and "comfortable". Who wants that over zoom-zoom? Show us some pics of those bikes so we can see just how awful and outdated they are. Otherwise, I might just buy one accidentally, throwing the interweb crabon market into a tailspin.

[EricEstlund]

Seems like those seat tube angles keep getting steeper and steeper. What's going on here?

What bikes are you looking at? A cursory glance of some of the big players top road models doesn't seem to show this- I'd be interested in seeing the bikes trending in this direction.

[bicycletricycle]

like any good post i did little to no research before posting :) , just seems that a bunch of the bikes that i want to buy would work except for the seat tube angle, perhaps i am mistaken and there is no trend and seat tube angles are stable.

What bikes are you looking at? A cursory glance of some of the big players top road models doesn't seem to show this- I'd be interested in seeing the bikes trending in this direction.

[Dead Man]

ok, but what's your seat tube angle?

itz like probably medium. :banana:

[mhespenheide]

like any good post i did little to no research before posting :) , just seems that a bunch of the bikes that i want to buy would work except for the seat tube angle, perhaps i am mistaken and there is no trend and seat tube angles are stable.

In my own completely non-thorough attention, I'd say that I think I'm seeing the opposite. When I got into cycling in the late 80's and going into the early 90's, any number of bikes had 73.5 or 74-degree seat tube angles. 72.5 or 73 seem more common now, particularly among the "big 3" US sellers: Trek, Specialized, and Cannondale. All three were heavily criterium-influenced and have retreated to a more stage-race geometry in their racing bikes, to say nothing of the "endurance" models.

Note that I'm 6'4" and -- out of my passing inattentive survey -- only really pay attention to 61cm/62cm/XXL bikes. The medium-sized and smaller bikes might be a completely different story.

But all of that might be confirmation bias, as I'm not interested in bikes with steep angles, so perhaps I just ignore them.

[Keith A]

...Just because we all have a drivers license, doesn't mean we can go out and handle an F1 racer. ymmv...Thread drift...this reminds me of an episode of Top Gear were Richard H. was driving an F1 car. Even though he seems to be a very experienced driver, sitting behind a real F1 was not easy for him (although I'm sure part of it was to make good TV).

[Kirk Pacenti]

Thread drift...this reminds me of an episode of Top Gear were Richard H. was driving an F1 car. Even though he seems to be a very experienced driver, sitting behind a real F1 was not easy for him (although I'm sure part of it was to make good TV).

Even if this was just made for good TV, I think it illustrates the point well.
Today, any affluent cyclist can have the very best equipment available and in some cases even better than pros get to ride. But like many things in life, just because we can, doesn't mean we should.

disclaimer: My mis-informed opinions are my own. As always, ymmv. ;)

Cheers,
KP

[ultraman6970]

Ultra agrees with carpediemracing.

[weiwentg]

Shorter femur riders (think Japanese as a general population, for example) need a steeper angle. My bike has a 75.5 deg STA. With 73 STA I was slamming my saddle forward on a zero set back post and sliding so far forward I'd sometimes slide down off the nose of the saddle.

Funny, I had a Chinese rider make the same remark to me. I'm also Chinese. My STA is 76.

I'm not seeing seat angles in general getting much steeper in the smaller bike sizes, insofar as I've been paying attention. Specialized and Gunnar have relatively step STAs in the smaller sizes, but I think that's been true for some time.

[lukeheller]

just seems that a bunch of the bikes that i want to buy would work except for the seat tube angle...


Ditto. Throw in the desire for Brooks saddle with short rails = screwed. I don't even bother at this point. 72* STA at least for me or nothing.

And it's a shame that the bicycle industry must cater to the market's delusions that they'll be a pro. Or do they? Would the masses be just as happy to ride more comfortable bikes with slacker angles? I would bet yes. But I'm no expert.

[bicycletricycle]

Ya, that brooks is a killer, need a way back post and a way back seat tube angle

[chismog]

Does it have anything to do with OS seat tubes and tire clearance? I have two custom frames with (otherwise) all-day geos, big OS tubes, and clearance for 28s.

It's feasible that a bike with big tires and an OS seat tube might have clearance issues with a lower angle seat tube. A half degree seems almost like a design consideration since it can't have a huge change on how the bike is going to ride.

One of my frames was built by niccrump, maybe he has some input...