the ride quality of different materials

[eddief]

I know this could be a religion and politics sort of topic, but the certainty of the opinions on each side drive me a bit crazy. I'm in the process of believing my Giant OCR C really does have a different road feel/ride quality than my other rides. Not radically better or worser, but definitely different than my other steel rides. I'm enjoying the ride a lot; which I know is the most impt. But wouldn't the physics and other esoteric sciences support that similar dimensioned and inflated bikes made out of different materials ride differently?

Here is quote from a thread on rbr and I'm wondering if science supports it or not:

"The "ride quality" of a frame and fork is determined by two things: wheelbase (longer is smoother) and the fork. Since the fork is cantilevered off of the frame, it is free to flex to absorb some road impact. The rest of it is in our heads. Bicycle frames are ineherently stiff in the vertical plane. Any deflection will be so small that it will be masked by the far greater deflections in tires, stem, seatpost, saddle, and handlebars.

It's like arguing which car has a smoother ride, the one with leather seats or the one with vinyl seats."

[obtuse]

is this a trick question?

obtuse

[Fat Robert]

round wheels ride well

square ones ride like crap

[Grant McLean]

Here is quote from a thread on rbr and I'm wondering if science supports it or not:

"The "ride quality" of a frame and fork is determined by two things: wheelbase (longer is smoother) and the fork. Since the fork is cantilevered off of the frame, it is free to flex to absorb some road impact. The rest of it is in our heads. Bicycle frames are ineherently stiff in the vertical plane. Any deflection will be so small that it will be masked by the far greater deflections in tires, stem, seatpost, saddle, and handlebars.


Frames (and most components) also flex in torsion. (twisting)
This affects the ride a lot. Good or bad: depends on
the purpose, the rider, and the amount.

g

[David Kirk]

I"ll bet I'm in the minority if not alone in thinking that the ride of different materials will be different because of the differences in material hardness. All else being equal (which it never is) the softer material (carbon/epoxy aint too hard) will have less road vibration (feel, feedback, road buzz...chose your own words here) than a harder material (steel maybe?). The "all things being equal" deal is the wrench in the works. It assumes that you have the same diameter and wall thicknesses regardless of material. Because of the mechanical properties of the different popular materials this is rarely the case. Ever heard of a .4mm carbon tube?

That said..........picture baseball bats made of all the popular bike frame materials. The diameter and wall thicknesses of the materials would vary with the material and would give each tube has the same stiffness, regardless of material. Now picture swinging this bat as hard as you can at a telephone pole (stupid I know but I was bored a lot as a kid and I could hit the pole beacuse it never moved......i'm not too good at "ball" sports). Use your imagination and think about what it would feel like to your hands as the bat wacks the pole. They would have distinctly different feels and sounds even though they are all the same stiffness. This is due to the hardness of the material. It's the hardness (all things being equal!) that determines how much vibration makes it to your hands.

Apply this too bike frames and you can see how the road buzz would be transfered (more or less) depending on the hardness of the material.

Think about how it aplies to musical instruments.......there's a good reason cymbols aren'ty made of wood.

I could go on but you are already bored and my wine glass is empty. Have a great weekend.

Dave

[Ginger]

Someone say Track?

Dave. I like that theory.

[eddief]

not sure how anyone could argue. I would guess that with the proper instruments that the deflection and/or the transmission of more or less vibration (buzz) would me measureable. Is that not what the Rinard tests were about?