Frame geometry and skidding/ back pedaling to stop
#1
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Frame geometry and skidding/ back pedaling to stop
So my first fixed gear was an se lager which has pretty relaxed road geometry. i have been riding my new vigorelli for over a month now and one of the big differences is how easy it is for me to stop using just my legs.
the lager i could skid but it was extremely difficult and i couldn't really slow down effectively using back pressure with my legs.
I'm relatively new to understanding road type bikes in general and geometry is a mystery to me as to why it makes such a drastic difference in performance. my knowlege really doesn't go past seat tube and head tube angle.
so is this pretty elemetary? has anyone else had experience with this? i just don't hear it mentioned much on these forums.
the lager i could skid but it was extremely difficult and i couldn't really slow down effectively using back pressure with my legs.
I'm relatively new to understanding road type bikes in general and geometry is a mystery to me as to why it makes such a drastic difference in performance. my knowlege really doesn't go past seat tube and head tube angle.
so is this pretty elemetary? has anyone else had experience with this? i just don't hear it mentioned much on these forums.
#3
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46/16 for the lager. 48/17 for the vigorelli. that's one gear inch different. i don't know how substantial that is.
#7
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it is a drastically easier to skid and to stop without skidding. skidding on the lager was nearly impossible. i can do seated skids with the vigorelli. there was no way i would ever go breakless with the lager and i've been breakless on the vigorelli with all the confidence in the world. (this is not a discussion on brakeless, we have plenty of that already)
i just can't believe it's all because of 1.5 gear inches.
i just can't believe it's all because of 1.5 gear inches.
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You are absolutely right in your perception. And it is not because of the 1.5 gear inch difference. It is partly due to the difference in geometry but is also due to the fact that you have moved from cheap, heavy, flexy steel tubing to high quality, light, stiff aluminum tubing. Just as the frame accelerates faster due to the stiff light tubing (as it was intended to do on the track) it can be brought to a stop faster. Less weight, less inertia, less effort needed to stop. Stiffer chainstays, more of your energy is conveyed from the pedals to the rear wheel.
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For what its worth I made the EXACT same switch of gear ratios - 48/16 to 48/17 - and it made a huge difference I thought. After riding around on a somewhat high ratio, even a slight switch made a difference in my ability to skid and stop.
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so right now im at 39/16, i bought a 14t cog, so will it be easier to stop when i go 39/14?
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https://www.sheldonbrown.com/gears/
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You are absolutely right in your perception. And it is not because of the 1.5 gear inch difference. It is partly due to the difference in geometry but is also due to the fact that you have moved from cheap, heavy, flexy steel tubing to high quality, light, stiff aluminum tubing. Just as the frame accelerates faster due to the stiff light tubing (as it was intended to do on the track) it can be brought to a stop faster. Less weight, less inertia, less effort needed to stop. Stiffer chainstays, more of your energy is conveyed from the pedals to the rear wheel.
=====
P=mv
=====
It's gotta be the geometry and maybe the different gear ratio.
maybe even a slight difference in geometry makes a huge difference in performance?!
Just like a small surgical correction to an ugly nose, can make a huge difference to a persons appearance.
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Dude, common. Running uphill is more difficult because the angle between direction of motion and gravity is greater, not because your momentum is bigger.
Momentum is actually smaller when running uphill, assuming you're slowing down.
Again:
P=mv
Momentum is actually smaller when running uphill, assuming you're slowing down.
Again:
P=mv
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Umm, alright. I was thinking more along the lines of distance running. The accepted technique is shorter stride, similar to a person naturally running uphill. Vague metaphor to bicycle geometry, I know.
(P=mv)/flying squirrel
(P=mv)/flying squirrel