Handling Effects of Shorter Stems (from the OT discussion in a previuos post on the New Sams in Sept)

[John Hawrylak]

In an earlier post on the new Sam Hillborunes coming in Sept,

 

“New batch of Sam Hillbornes this fall”     5/16/20

 

The discussion went OT to the longer top tubes RBW uses in the MIT Atlantis, and the need for shorter stems when using drop bars .  Patrick Moore expressed concerns about the stability of short stems:

 

“How do such short stems affect the handling of the Atlantis?”

 

I went to my copy of Bicycling Science, 3^rd Edition, 2004, and read the chapter on Steering & Balancing.  One main point made is the importance of Mechanical Trail, steering torque, and the fact the steering axis is inclined to the horizontal and is not vertical or near vertical on the stability of a bicycle.

 

I assume stability and handling are somewhat synonymous.  I made a new post for this issue

 

I could not find any discussion of stem length, except on pages 288-289, in a qualitative discussion on the importance of the ‘tilted’ steering axis.  I typed the words from this section below.  The text includes a personal communication from John Allen discussing the effects of stem length on stability. Instability section of Chapter 8 Steering & Balancing

 

 

Bicycling Science, 3^rd Edition, 2004,  pages 288-289,  Nonoscillatory Instability section of Chapter 8 Steering & Balancing

 

“ Who was the genius who thought of tilting a bicycle’s steering axis?  And was this tilting valued for its stability benefits, or for something more mundane like minimizing hand-force steering disturbances during stand up pedaling or preventing rearward bending damage from striking a pothole (Brandt 2000)?  The development of a tilted steering axis is one of the major mysteries of bicycle evolution.  John Allen (2001 personal communication) writes:

‘In the early days of the safety bicycle, the handlebars were placed close to the cyclist, as had been the tradition and necessary with high wheelers, with their very serious pitchover problem.  High wheelers had little or no forward angling of the front fork: it would not have been practical because it would have prevented the cyclist from standing over the pedals , and would have placed the force vector from pedaling too far from the steering axis, making steering difficult.  Bicycle evolution involved innumerable experiments, but the answer is most likely mundane: the fork was angled forward in order to keep the handlebars close to the cyclist, and for the front wheel to clear the feet, in spite of what intuitively would seem to be a stability reduction.  This development occurred before the discovery (by Major Taylor?) that a greater distance to the handlebars improved both power production and aerodynamics.  A longer stem also greatly improves stability when riding with one hand on the handlebar, an important side benefit which would not accrue simply by lengthening the top tube and keeping the fork vertical’”

 

It seems the only stability issue with a shorter stem would be some decrease in stability when riding with one hand on the bar.

 

 

John Hawrylak

Woodstown NJ

[Joe Bernard]

"It seems the only stability issue with a shorter stem would be some decrease in stability when riding with one hand on the bar."

As far as my not-an-engineer brain can tell this would only be true in a situation - like a flatbar- where the shorter stem moved your hands back exactly as far as the the stem reduction. Which is not the purpose James/Candice/Analog are marketing the 0 stem for. It's to use a frame you can ride riser are pull back bars with, and convert it to putting your hands in the same general spot with drops: Stem comes back, bars move forward. There should be no change in steering between the two setups.

[John Hawrylak]

Joe

The Bicycling Science chapter did not discuss the of bars, but all the figures were the standard -17° stem with drop bars.  So I would assume John Allen had drop bars in mind in his 2001 communication to Wilson.  Also, Patrick's question concerned drop bars, not swept back bars.

My takeaway from the chapter is the shorter stem has no 'fatal flaws' except some reduction in stability when riding with 1 hand on the bar per a qualitative discussion and lack of any discussion on hand position vis a vis stability in the rest of the chapter on Steering and Stability.  The reduction may be small and easily adaptable.  

As far as the zero length stems, I read the Analog description of their stem and of course they did not discussion any 'cons' or 'unintended consequences" of their design.  

I agree if your top tube is too long, their product is required and you need to live with the consequences. 

John Hawrylak

Woodstown NJ

[Nick Payne]

There's a discussion of this exact topic here: https://www.cyclingabout.com/steering-masterclass-how-stem-length-affects-your-steering-speed/.

Nick

[Drw]

I feel like Joe said it pretty good and in a way that made sense to me in the other post, which I will now butcher. The bike doesn’t care how long or short a stem is, It only cares how far beyond or behind the steering axis your hands are.

I don’t know if that’s true but it reflects my experience.

[Joe Bernard]

"I agree if your top tube is too long, their product is required and you need to live with the consequences."

To be clear, Analog is not promoting the 0 stem as to adapt drops to bikes that have too-long toptubes. The idea is the toptube is just fine for trail riding without TCO, and the stem with flared drops is part of that design plan.

[Alex Wirth- Owner, Yellow Haus Bicycles]

As a contributor on this topic with very recent experience....I switched from 80mm stem/drop combo to 0mm stem/drop combo without any perceptible drawbacks so far (other than an oddball aesthetic).

I’d guess I’m in the realm of an albatross or albastache/50-80mm stem with this new set up.

https://www.instagram.com/p/CAb1vs3gLhN/?igshid=wnzwckinbawf

Alex in Rochester

[Alex Wirth- Owner, Yellow Haus Bicycles]

Quick clarification....no *handling* drawbacks.

I don’t think there’s a way around it but since the bar covers the quill adjusting bolt the bars need to be removed any time you need to adjust height. A little fussy when dialing in height. Thought it was worth mentioning...

[Bill Lindsay]

Building on Joe's comment that the top tube is just fine, I was amused/intrigued by the Evil Bikes Chamois Hagar, LINK.

I started to look at the frame geo numbers and it's a pretty vanilla contemporary mountain bike kind of setup.  Put a flat bar and a medium length stem and you'd have a full rigid but otherwise normal mountain bike.  In other words, it looked to me like somebody took a normal mountain bike with a tall head tube and put a really stubby stem and dirt drops on it.  Voila, Monster Gravel, or whatever you want to call it.  

I ended up with a retired team bike that was too trashed to re-sell, and decided to run that experiment in reverse.  I swapped a stubby stem and dirt drops onto a normal mountain bike.  It ended up astonishingly normal.  I would call it a hair small for 5'10" me, but a 5'8" rider would be right at home on it.  Here's a flickr album of this quarantine project.

https://www.flickr.com/photos/45758191@N04/albums/72157714412160443

Big picture, think about it.  Some people ride 38cm wide drop bars and some people ride 48cm wide drop bars, and others ride 66cm wide drop bars, and they all do fine.  Some people ride 800mm flat bars and others ride 550mm flat bars and they all do fine.  There is nothing objectively bad about a short stem, provided the bike fits.  

Bill Lindsay

El Cerrito, CA

[Max S]

http://www.peterverdone.com/some-bikes-are-more-evil-than-others/

http://www.peterverdone.com/airspeeder/

http://www.peterverdone.com/2018-pvd-bird-of-prey/

- Max “color me intrigued” in A2

[Doug Hansford]

Those are nice looking builds. Thanks for sharing Max.
Doug

Sent from my iPhone

> On May 22, 2020, at 1:44 PM, Max S <msh...@gmail.com> wrote:
>
> http://www.peterverdone.com/some-bikes-are-more-evil-than-others/

>
> http://www.peterverdone.com/airspeeder/
>
> http://www.peterverdone.com/2018-pvd-bird-of-prey/
>
> - Max “color me intrigued” in A2
>

> --
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[Bill Lindsay]

That Peter Verdone guy has a very 2020 rhetorical style.  Paraphrasing:

-Here's the way things are

-Anybody who disagrees with me is uninformed

He may be totally right on many/most points.  I guess if his objective is to improve his designs for an audience of one (himself), then he doesn't need to be persuasive or humble.  

That said I'd totally love to ride that Bird of Prey bike.

Bill Lindsay

El Cerrito, CA

[Max S]

He does build all these things himself and does his own test "flights" and isn't shy about relating failures (can't find the link, but there was a recent crash involving his own carbon/metal bar and broken bones). 

If you scroll down in this post, he shows a good comparison of rider contact points and where the wheels end up: https://www.peterverdone.com/baron-review-offroad/ 

In some ways, I agree that his style is a bit more cocky / confident / declarative than warranted. In other ways, I find it a bit more palatable than the all-too-non-committal, "everything is subjective" style that I think is more the current trend. But we're getting into philosophy... I'd love to ride one of his bikes, although my riding currently doesn't include "getting rad" offroad. 

- Max "feeling fast in my WFH lounger" in A2

[Patrick Moore]

This has been an interesting discussion, and I've learned something, namely that it seems that if a bike is designed to situation your weight in a certain position, you can mix up the bar and stems as long as your maintain the range of positions the bike was designed for. Stated like that it seems obvious, but it took a breakdown of component ideas for me to see the obviousness. A couple online essays I read in the interval support the conclusion of this discussion.

This implies of course that you can't rely on a short stem and bar (or, conversely, very long ones) to make a too-long bike fit and handle properly because the frame is not designed for such a short reach, no matter how achieved.

For about 18 months I owned one of the original green Sams with cantis, a 56 cm st and a 59 cm tt. I got rid of it for several reasons, but one reason was that the reach to the Noodle bar was too far with the bar as low as I wanted it (sorry, I do not agree that bar height doesn't matter; it matters if it matters to you the rider, tho' there is a range of reach versus height tradeoffs that work for a given preference). I wonder how it would have worked with a 6 cm stem, say. As I said, my Riv Roads use 8 cm stems, shorter than usual on road bikes, and they handle not only impeccably to my taste, but they are my handling benchmark. Of course, there are all sorts of variables, including notable saddle setback wrt the bb, thus sta, but 59 cm even with a shallower sta than my road bikes was still ~1.5 to 2 cm too long to use what I considered normal stems. But a 6 cm? Perhaps that would have worked.

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-----------------------------------------------------------------------

Patrick Moore

Alburquerque, Nuevo Mexico, Etats Unis d'Amerique, Orbis Terrarum

[Patrick Moore]

I should have added that in retrospect I've experienced the viability of short stems myself: I've built many long tt mountain bikes up with drop bars using radically upjutting stems (10 cm DD, Tioga T-Bones) with effectively very short reach; not 0, but certainly less than the 8 to 10 I expect on a road bike that fits. Handling was --- like that of a nice mountain bike.

[Joe Bernard]

I think there's more psychology involved in what we think a bike is "supposed" to look like than we admit to. If my brain thinks a long-ish 7-shaped stem is the right way to run a dropbar, I'm liable to think a short stem handles weird because the look convinces me it will handle weird.

[lambbo]

$20 way to test a 300mm stem if you don’t mind chinese made.
https://www.ebay.com/p/534752766?iid=262029398924&chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&itemid=262029398924&targetid=884692771401&device=m&mktype=pla&googleloc=9004358&poi=&campaignid=9344508178&mkgroupid=100238954131&rlsatarget=pla-884692771401&abcId=1139336&merchantid=102014203&gclid=EAIaIQobChMI9Kr3jPjI6QIVloTICh3puQd-EAQYBiABEgJbYvD_BwE