I am a newbie to bent riding after many thousands of miles on wedges.
I am not an expert in cycling architecture, but after a couple of
hundred miles on my Corsa, it seems like a great balance between
pedaling efficiency and vertical compliance. I really enjoy the feel
of the input through the pedals and the way in which the bike flexes
over the common undulations in the road. More abrupt bumps, of
course, are a real pain in the butt, but overall, what a nicely
engineered mono tube bike structure. I'm amazed at the the fine tuned
engineering of my Bacchetta.
[email hidden] (RCPINTO) wrote in message news:<[email hidden]>...
Quoted message said:Alan Mushnick wrote;
Quoted message said:Isn't there an inherent structural advantage of triangulated frames
over monotubes? This seemed to be a big part of the discussion of the
Easy Racer vs. Rans V2 debate.Hi Alan
Designers make choices all the time about how to balance the sometimes
conflicting goals of weight, stiffness, aerodynamics etc. of frames.Many times frame geometry and material, or the style of bike (or trike) and
wheelbase make the designers choices easy.Two entirely different stiffness issues are involved here, those against
pedaling forces (fairly important IMO) and vertical stiffness. I have ridden
truss frames out there that are very vertically stiff, but have
wagging/twisting bottom brackets from a lack of horizontal stiffness. Pedaling
forces act on frames in both the horizontal and vertical plane.Vertical stiffness is not always a good thing on bicycles, you have to
consider that you have a human engine on board, and bumpy roads to contend
with. If a frames stiffness against pedaling forces also makes the frame a
jackhammer vertically, you only have the tires and the seat cushioning to act
as springs between you and the road.Also, making a frame lighter by triangulation can make a bike slower by
increasing the frontal area of tubes under the rider, and also by requiring
lower pressure (generally wider, heavier, lower performance) tires for
equivalent rider comfort. A bikes frontal area and the tires rolling
resistance are the two dominant factors in efficiency on most courses.Weight undoubtedly sells bikes- but improved aerodynamics and lower
rolling resistance makes them more efficient on the road.As far as triangulation always yielding lighter frames... the bare
titanium Bacchetta Aero frame weighs 3.5 lbs and has what I feel are the ideal
tradeoffs of weight, low frame frontal area under the rider, and some passive
suspension vertically...but still stiff enough against pedaling forces for high
transmission efficiency.Our steel frames weigh about 3 lbs more and are stiffer vertically, but
still have a good amount of passive suspension to augment the tires and seat
cushioning's road shock absorbtion...VERY important to our bikes performance!That's what is great about the world of recumbents today, everyone can
make a different choice about what is most important to them, and choose bikes
with greatly different characteristics and abilities!Rich Pinto
Bacchetta Bicycles