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It doesnt matter if you are going 1mph, the speed of light or 100 times the speed of light. If you where in a car and turned the lights on the light would race away in front at 186000 miles per second...... Any physicist would agree with that statement 100%
Yes the speed of light is always 186000 miles per second.......> RELATIVE to the observer
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Time for an update-
Nerd is basically right on seat bounce and the relativity.
FTE gets the "out of his element" award for trying the "appeal to authority" fallacy on a technical topic! Bad form, very bad. That tactic works for juries and judges, but not for technical facts.
The secret to getting your head around real seat bounce physics, and not the spring stuff, is understanding what happens when you approach certain jumps and where your CG is, and how you move it.
Think of the opposite of seat bounce, the BMX move called the Manual, where you approach a jump with CG high (standing up more) and then with the right move at the jump, they keep the trajectory flat and don't jump up. Nerdy got a killer shot of Stewart doing it at Troy on a 125. There was a section that everyone on the track but Stewart had to jump into, and he figured out how to hit it flat out, standing, front wheel up, and manual it. It was way faster.
Approach a jump sitting and get your weight lower, and you do the opposite of what Stewart was doing at Troy. When you translate forward motion to vertical, you feel the acceleration in the "up" direction, like a strong elevator effect. This is mistaken for a spring "bounce." You do feel something, but its just because you move up and feel it.
No one should ever argue that seat bounce is because of a spring after seeing all the pics we used to post of top riders seat bouncing, and they leave jumps sitting with rear wheel digging in and suspension compressed at the moment they leave the jump. Springs have to move to release energy, and to make the spring thing work, it has to be touching the ground as it releases, not air. This is where one is reminded also that springs on race bikes are damped, exactly to prevent sudden release of energy in the vertical direction.
As far as Thede trying to explain it via FTE's second hand comments, it reminds me of when we asked KW about it and he wasn't buying the physics. He said he knows he can change his settings and seat bounce more or less. Well, he's KW, that's different. He's talking about refining something and not how the move really works. KW can figure out how to make a bike do anything, but explaining it never was his strong point.
Yes, of course.
If you had a space ship with headlights that could go the speed of light, and you turned the headlights on, you would see dark. Incredible things happen at the speed of light, and there are some things that can't happen.
If I didn't know better, I would think I was right and left the thread alone because I was working, and because I knew I was right and ultimately didn't care if everyone else didn't think so...
Nice seeing you again.
People go to carnivals and ride rides to feel acceleration. Same thing!
TFS wrote: Sup foo!?
Yes, of course.
If you had a space ship with headlights that could go the speed of light, and you turned the headlights on, you would see dark. Incredible things happen at the speed of light, and there are some things that can't happen.
That's some funny shit and it proves what some of us have known: TFS failed freshman physics.
Nerd is uneducated so he's excused from not knowing (being arrogant about it is another issue). You on the other hand claim to be an expert.
Thanks for playing TFS...time to hang up your keyboard.
I put your F in bold so you wouldn't have to spend all day googling it.
Pit Row
Seat bouncing is a good technique to use when you’re approach into a jump is short and you need more height and/or distance and/or don’t have enough time to stand up for the jump. Since you’re sitting on the seat your body weight is going to go straight into the bike and therefore compress the rear suspension more, causing it to rebound harder and give you more lift (airtime) out of the jump. If you were standing your legs could absorb some of the compression and rebound, keeping you lower. When seat bouncing clutch and throttle control are very important and usually pulling back on the bars at the right time is also important for these two things are what control whether your front end is high or low. You see, you have to deliver the power to the rear wheel just right with the clutch and throttle as that rear wheel compresses into the jump and rebounds out of the jump. This is an advanced technique and even then can only be used on short approaches where you’re accelerating all the way through the compression part of the jump. The jump face also has to be smooth with no kickers in it.
Check out my All About Jumps and Whoops DVD for all the details. Now 50% off. http://www.gsmxs.com/dvds/volume-2/dvd-3-all-about-jumps-whoops or better yet my newer DVD Volume 3 DVD # 7 Seat Bouncing and Launching Techniques; http://www.gsmxs.com/dvds/volume-3/vo3-dvd-7-motocross-absorb-scrub-whi… See a free preview and order or Stream online.
The speed of light is RELATIVE to the person observing it.
Someone may have caught this, I did not read the entire thread.
"In 1905 he realised how it could be that light always goes at the same speed no matter how fast you go. Events that are simultaneous in one reference frame will happen at different times in another that has a velocity relative to the first. Space and time cannot be taken as absolute. On this basis Einstein constructed the theory of special relativity, which has since been well confirmed by experiment."
http://math.ucr.edu/home/baez/physics/Relativity/SpeedOfLight/headlight…
You're new to Vital Gary......
Cue TFS and Nerd in 3,2,1...
Good to see you on here...
This battle goes back years, I started out 2 laps ahead and Nerdy is about the only one that keeps the pace!
Look at the above pic. This proves the spring has nothing to do with the "bounce." A compressed spring releases no energy. The energy is released as the spring extends. This one is not going to extend until the rear wheel leaves the ground. This is all you need to prove that the bounce has nothing to do with the spring.
What you "feel" is actually acceleration in the vertical direction due to translating a horizontal velocity to the vertical. The faster you translate horizontal velocity to the vertical, the stronger the "spring" feel, only you can do the same on a bike with solid suspension, a BMX bike, or even on a wakeboard.
I have no doubt that KW, yourself, Thede, and others with experience can argue all day that suspension and settings matter, and that would be true, they do. But the key aspect of seat bounce, getting more height, is not spring related, as the pic above proves beyond any doubt.
The spring does not create upward lift because the rear suspension does not start to extend, or rebound, until after the rear tire leaves the jump face. All seat bouncing does, by bottoming the rear suspension, is allow the bike to leave the jump face at an angle, or trajectory, that's as close to the steepest angle of jump face as possible.
When standing, your flexing legs act as dampers and causes the rider to be a dynamic force on the bike, which absorbs some of the vertical lift, and causes the bike to leave the jump face at an angle that's less than the angle of the steepest portion of the jump face. The Rider's CG has little to do with it. You can get a similar effect if the rider's legs are locked straight, but it's easier for the rider to became static on the bike if he is in the seated position.
Actually, no, buddy. I respect that you are an engineer and that I (and Nerd) am not. I deferred to your explanation. But Paul Thede is every bit as much an engineer as you, and more in the sense that he's been working out engineering solutions to motocross suspension for at least as long as you've been figuring out why aircraft fail.
The difference is that I think he's more vested in an honest answer rather than talking crap on people on an internet forum. All I said is that having accepted what you've said in the past, I'm inclined to defer to Paul under the circumstances. I've got no case to make, it was just a comment in a post that's rerun a ton over the years. I honestly don't care who is right about how it works, and God forbid you should ever be wrong.
If you want to go back to Matthes' podcast and clarify how I misunderstood him on stored energy in the spring and how that plays out in the technique, I'll accept that. It was a really great discussion on far more suspension issues than seat bouncing; I'd think you'd be interested in that as an engineer and a moto fan. Better yet, if you have any writing impulses left, why not talk to Paul and vet the issue and write an article transcribing the interview.
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