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. On Thu, May 21, 2020 at 6:12 PM 'John Hawrylak' via RBW Owners Bunch < rbw-owners-bunch@googlegroups.com> wrote: > 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, 3rd 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, 3rd 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 > > -- > You received this message because you are subscribed to the Google Groups > "RBW Owners Bunch" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to rbw-owners-bunch+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/rbw-owners-bunch/7aeafb41-aca2-4594-8bc3-e999739c6c10%40googlegroups.com > <https://groups.google.com/d/msgid/rbw-owners-bunch/7aeafb41-aca2-4594-8bc3-e999739c6c10%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- ----------------------------------------------------------------------- Patrick Moore Alburquerque, Nuevo Mexico, Etats Unis d'Amerique, Orbis Terrarum -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To unsubscribe from this group and stop receiving emails from it, send an email to rbw-owners-bunch+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/rbw-owners-bunch/CALuTfgt9wneZX5-vLBYHKtbb2XTrnYncGNNzy-GzcbGnvenXYg%40mail.gmail.com.
