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Old 09-05-2014, 02:17 PM   #201
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What's the meme for "you're retarded"? When you resort to meme's instead of good concrete logic based on science then it just makes you look even more retarded.

Good luck with business calculus.


Cos your science and math doesn't apply to this rider's crash you dumb how many times I gotta tell you boy? This isn't a space shuttle going speed or sound. drag applies to endo? It's so small that shouldn't even be calculated, like jumping up and saying the earth weighs less for a split second. GTFO here.
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Old 09-05-2014, 02:18 PM   #202
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Old 09-05-2014, 02:22 PM   #203
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I would tend to disagree with you based on momentum and center of gravity relative to the axis of rotation, in this case the front axle. While I'm sure drag imposes some opposing force on the rider / motorcycle, I don't think it's nearly enough to state that it's "easier" to induce this rotation at a lower speed.

In this case, you have both the forward momentum at the center of gravity (above the axle) moving forward, plus the force of deceleration between the ground and front tire acting at roughly 1' distance below the axle. The faster you're going, the stronger those rotational forces are going to be.

Honestly not trying to be an here: I'm not always great at describing things in words, I'd be happy to draw a diagram of exactly what I'm trying to describe if it would help.
Momentum is p=mv while drag stated earlier has a v^2 term so drag will grow much faster than momentum. Not saying Stoppies or endo's can't be done at higher speeds but only that it takes more braking force to overcome the drag.
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Old 09-05-2014, 02:23 PM   #204
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*yes that's oversimplified and negates gravity, but I intended only to highlight that the most important factors in this dynamic only increase with increased velocity, assuming you're operating at the tractive limits of the tire.
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Old 09-05-2014, 02:27 PM   #205
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Cos your science and math doesn't apply to this rider's crash you dumb how many times I gotta tell you boy? This isn't a space shuttle going speed or sound. drag applies to endo? It's so small that shouldn't even be calculated, like jumping up and saying the earth weighs less for a split second. GTFO here.
I just calculated drag and how much it resists endos. The answer is more than your internal combustion engine out of a sports car can produce.

When was the last time you took a physics class? Fluid dynamics class? Dynamics class? Aerodynamics don't need that much speed to make a difference.
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Old 09-05-2014, 02:29 PM   #206
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*yes that's oversimplified and negates gravity, but I intended only to highlight that the most important factors in this dynamic only increase with increased velocity, assuming you're operating at the tractive limits of the tire.
Gravity is constant at any speed.
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Old 09-05-2014, 02:32 PM   #207
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Old 09-05-2014, 02:32 PM   #208
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Locked rear at that speed, heading into a corner, you go from being a pilot to passenger. Great if you are on motard but not on a supersport. Nothing but modulating the front brake and (counter) steering could have save any of them.

The other thing that is hard to reproduce is the lever effort you exert and speed at which you exert it, in an actual panic situation. You're him and come in to a corner (off line) thinking you will follow another bike through at twice the speed you thought the are actually going, realize it and start to check up, you're on the brakes but its clear you are going to hit them really hard, squeeze brakes more, more, who wouldn't panic? OR you're her thinking, "man that was a rush, oh I got to slow down, didn't think I would get to this corner that fast, oh wait, no not that slow" them BAM! "What the... was that bike upside down... brakes brakes brakes, oh I'm going to run this guy over... more brakes. Getting hit by the wrong end of bike from behind would make anyone here panic! That's tough to recreate even when you are trying.

In fact I change my theory. These endos were NOT cause by the prevailing laws of physics, they were cause when the vacuum generated by panic induced rectal evacuation, sucked the rear tires off the ground rotating the bikes end over end, only when the riders finally exhaled as they flew in the air did the bikes finally disengage from their seats.
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Old 09-05-2014, 02:36 PM   #209
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But you didn't figure in gravity into your answer, did you? Nah, can't cause you Physic majors don't know what the it is.
When comparing two situations when there are constants you can ignore them. If I was calculating how much braking force it would take to do an endo I would need to calculate gravity but since I'm not doing that then gravity is irrelevant to the discussion of what speed is easier to endo at.
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Old 09-05-2014, 02:38 PM   #210
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I endo'ed b4 t3 at TWS (Texas World Speedway) same day and the rear came up, I still made the turn tho got some footage I may post
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Old 09-05-2014, 02:40 PM   #211
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Gravity is constant at any speed.
not warp speed



camiseta camiseta keep calm and bazinga ilustracao
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Old 09-05-2014, 02:41 PM   #212
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Quote:
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Gravity is constant at any speed.
yeah, I meant to have that comment with the diagram, didn't realize this was so popular and so didn't refresh before just posting.

If we were debating easier to endo at 120 mph or 160 mph, I might buy into drag having an effect, as the drag force might have a greater effect than the force of deceleration, as the traction of the tire is limited by the tire compound, drag is only limited by velocity. However, I'm not sold on the real-world explanation between 20-80 mph.
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Old 09-05-2014, 02:55 PM   #213
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If it makes a difference from 120-160 it will make a difference at 20-80. Motorcycles have terrible aerodynamics, especially with the rider sitting upright like with braking.

Another thing to consider is if a bike/rider have 50/50 weight distribution then at 20 mph it will be 49/51, then at 80 mph it will be 40/60(random numbers used to explain a concept. That means the braking force is going to have to overcome that weight bias before flipping the bike.
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Old 09-05-2014, 03:17 PM   #214
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Hahahahhahaahh at some of these replies
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Old 09-05-2014, 05:07 PM   #215
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All you guys and arguing over this are gay. Honestly, who gives a fk!? It's a crash. Instead of enjoying the video, you choose to argue about that doesn't even matter.

Anyways, I'm out. Catch you ladies later.
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