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a modern litre bike will go from 60 to 0 in about 2.3 seconds or about 100 feet. But let me share some simple math with you. At that rate if you double the speed to 120 mph it will take you twice as long to stop, about 4.6 seconds. BUT IN THE TIME YOU WILL TRAVEL 4 TIMES THE DISTANCE or 428 feet. At 3 times 60mph or 180 mph it will take you 3 times as long or about 7 seconds to stop. BUT YOU WILL TRAVEL MORE THAN 900 FEET.

In other words at 180 mph if someone pulls into the road the length of 3 football fields down the road you are still going to be doing 60 mph when you hit them. You’ll be going even faster if it takes you more than 0.37 seconds to recognize the threat and pull in the brake lever.


Sincerely,
Too Much Time On My Hands
 

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dirkmc3 said:
a modern litre bike will go from 60 to 0 in about 2.3 seconds or about 100 feet. But let me share some simple math with you. At that rate if you double the speed to 120 mph it will take you twice as long to stop, about 4.6 seconds. BUT IN THE TIME YOU WILL TRAVEL 4 TIMES THE DISTANCE or 428 feet. At 3 times 60mph or 180 mph it will take you 3 times as long or about 7 seconds to stop. BUT YOU WILL TRAVEL MORE THAN 900 FEET.

In other words at 180 mph if someone pulls into the road the length of 3 football fields down the road you are still going to be doing 60 mph when you hit them. You’ll be going even faster if it takes you more than 0.37 seconds to recognize the threat and pull in the brake lever.


Sincerely,
Too Much Time On My Hands
wow...its a good thing my bike only does 176mph. :eek:nfloor :banana
 

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Good one. Something to think on...
 

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malik ross said:
wow...its a good thing my bike only does 176mph. :eek:nfloor :banana
Damn, I need a liter bike...my bike only does 148mph (not that I would know anything about going that fast just outside of Brodhead :eek: :eek:nfloor )
 

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Isn't there usually the option of going around someone/something to possibly avoid hitting them . . . just a thought :2eek
 

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I'm sure their accelleration away from you plays into this equation as well.
 

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Fun with math, but yes how do you figure in the fact that "said" vehicle which pulls into your lane accelerates in the same directions as you are traveling. Then you can factor in maneuvering the bike to avoid "said" vehicle.

All in all the math is impressive. Just please ride responsible and you would never be in that situation.
 

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When he cut and pasted from the original there wasn't anything there about that stuff...
 

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Yep!

Jokertlr said:
When he cut and pasted from the original there wasn't anything there about that stuff...
Must understand the math, most inexperience drivers only look 5 to 7 second in front of them, at the speeds your talking about, in open road it will be necessary for the ride to be focus on 15 to 25 seconds in the future, even then you could never be fully prepare for that idiot driving the SUV going 130, with enough weight that even when you begin deceleration, it will not matter because he will run right over you.

We are alone out there, better learn our math, crap, I failed algebra twice...
oh well, what is an un-educated simpleton to do... :lao

:cheers
 

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now does this include engine braking? we need to know all this stuff so my math can come out right. What if ur going thru a turn? ur velocity decreases.

i don't have to worry bout this stuff, cuz my bike isn't runnin. ;)
 

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incognito0160 said:
now does this include engine braking? we need to know all this stuff so my math can come out right. What if ur going thru a turn? ur velocity decreases.
Dirk is assuming a steady-state 1.2g braking force. That's on the optimistic side if anything.

I have been able to record as high as 1.4g instantanious g loading, but that was in my car, on DOT race tires... I don't have any data traces on bikes, but I'd imagine they're about the same...

1.2 gs on a bike is really getting on the binders HARD... race track, floating the back-end style! That might be aproachable with street tires, but MAN, they better be warm and the rider DAMN good at modulating those brakes agianst impending lockup/endoing.

Case-in-point, it will take mere mortals LONGER TIME and MORE DISTANCE to stop than even Dirk's numbers suggest...
 

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friday night, it was very hot at the track..kinda greasy, at the end of the 1/4 mile, 145 mph, I was hard on the brakes to try and stop for the turn-around and my rear brake locked up...tried again..same thing..not a good feeling. Must be nose diving and unloading the rear.
 

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dirkmc3 said:
a modern litre bike will go from 60 to 0 in about 2.3 seconds or about 100 feet. But let me share some simple math with you. At that rate if you double the speed to 120 mph it will take you twice as long to stop, about 4.6 seconds. BUT IN THE TIME YOU WILL TRAVEL 4 TIMES THE DISTANCE or 428 feet. At 3 times 60mph or 180 mph it will take you 3 times as long or about 7 seconds to stop. BUT YOU WILL TRAVEL MORE THAN 900 FEET.

In other words at 180 mph if someone pulls into the road the length of 3 football fields down the road you are still going to be doing 60 mph when you hit them. You’ll be going even faster if it takes you more than 0.37 seconds to recognize the threat and pull in the brake lever.


Sincerely,
Too Much Time On My Hands
I believe the math, but I don't know how accurate the last statement is. I would be willing to bet that given 3 football fields a person could stop with room to spare. Just my opinion though.
 

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2002 Busa SE said:
friday night, it was very hot at the track..kinda greasy, at the end of the 1/4 mile, 145 mph, I was hard on the brakes to try and stop for the turn-around and my rear brake locked up...tried again..same thing..not a good feeling. Must be nose diving and unloading the rear.
Have you set your sag? I was going in ~135mph indicated down into corner 1 with my defective speedo (which reads 14% lower), and I didn't touch to the rear breaks, slowing down without any problems into the turn.

Prehaps you need to talk to Todd and/or Trackside :D.
 

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and I didn't touch to the rear breaks, slowing down without any problems into the turn.
your bike is over 100 lbs lighter!!!!!!!!
everything is adjusted on the hard side...I did the front forks almost full hard on the compression to see if it helps..it didnt...
 

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On second thought, even with your suspension sorted out, I'm not sure if you need your rear brakes at all. With all that weight shifted to the front, you probably don't get much stopping power from the rear anyway. I rarely use my rear brakes on the street, and was told at the trackday not to use them at all. IIRC, there was a busa out at Blackhawk as well... Maybe somebody more experienced can chime in.
 

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dorao said:
On second thought, even with your suspension sorted out, I'm not sure if you need your rear brakes at all. With all that weight shifted to the front, you probably don't get much stopping power from the rear anyway. I rarely use my rear brakes on the street, and was told at the trackday not to use them at all. IIRC, there was a busa out at Blackhawk as well... Maybe somebody more experienced can chime in.
I flipped mine on the front straight of BHF with no rear brakes... if I had used them, would I stil have flipped it? dunno...
 

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I would also like to see in that equation...... how far your body would fly after hitting said vehicle...... do you have to take wind speed and direction into account then? :slaugh
 
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