Who knows stopping distance from 150 mph?

[Mont]

I am still reading this thread interested as a full load capacity rider. Everyone talks about how weight slows you down getting up to speed, but little is said about the same thing on the other end of the track. My kid turned a 158 in his truck at Texas last time, and got distracted coming through the traps. The rotor and brake in the picture were new, and had only 300 miles on them when it happened. The color change speaks for itself.

Bikes have 4 braking methods: Wind, front and rear brakes and engine compression. Anyone that has made the mistake of popping up at speed knows all about becoming a human parachute. Same thing goes for anyone that has downshifted too hard and slid the rear tire. If you think about how small the area of the brake pads really is, along with the contact patch for both tires, there's really not much to work with there. There's also a lot of heat to dissipate to avoid glaze.

 

[dadofthree]

A Dodge, come on

 

[outlawbusa]

I thought that was an odd looking horseshoe?

 

[StrtRac3r]

Did the officer yell SURPRISE!?!

Lol..... I don't know what your talkin about.

 

[IG.]

Tuf, no offense taken. Did you ask Brendan to explain the silverfish looking deposits on the pads in the picture I posted? Aside from a specific case, a tech support person would give a generic answer - unless pointed out to a specific issue. It's human nature. Also, did you ask him why groves develop on the rotors, especially on those that have been used and abused over years, miles, country riding, and track days?

The reason I deviated from the original question was because it is less important to know the exact distance, but more important to know that it takes a lot longer to stop from 150. I also provided my estimate of the distance. Would you agree with the number?

I feel you brought up a good question highlighting the challenge of stopping from high speeds. It also helps to comprehend the issue by understanding why it takes so much distance, and that is why I went into so much detail about it.

The next logical step would be for you to explain how to properly slow down from 150 - perhaps in a separate post. Just a suggestion. I have a lot to say about it, but it would only be fair if you had the first word.

 

[dadofthree]

Lol..... I don't know what your talkin about.

Yep, cause that's pin it time

 

[Poppy]

I'll say approximately 1108.18 feet

 

[outlawbusa]

I'll say approximately 1108.18 feet

Bike Safer.com: Motorcycle Braking Time

 

[Dookoo]

Bike Safer.com: Motorcycle Braking Time

Thanks for the link and the most helpful answer yet!

 

[Mont]

A Dodge, come on

It's got enough jugs to make two great bikes, plus a Harley When he asked for head bolts for his BD, I knew he was serious about the 170 club.
Stopping from 150 is still stopping, Dodge, Suzuki, or anything else moving that fast.

Deferring to the experts, it appears a perfect 150 MPH run on a bike would take right at one half mile total. That's something most people will never do. I suspect it would be impossible at full load on a Gen 1.

If anyone would like to post pointers on the stopping part, I would find that information useful.

 

[Tufbusa]

Hot damn, we finally got someone to do a google search

I did a google search as well before I posted this thread. I think 1108 feet is a fair number. Since I have never measured the stopping distance I really don't know how far it takes for "ME" to stop from a buck fifty. However, I can tell you that I've performed a stop from that speed then looked back at my brake marker and it was a long fn way, I'd guess around a thousand feet or so.

The answer to the question is: There is no correct answer! Braking is a learned skill and the stopping distance depends entirely on the skill of the nut behind the bars. If we took everyone who has dropped in on this thread and had a braking skill test we would find a broad range in the stopping distance. Our beloved busas will burn speed much better than you may think. However, there are some requirements we must meet in order to tap into her maximum braking zone. First is the laws of physics "You MUST load the tire before you work the tire" Second, we must provide her with enough grip to lift the rear tire without loosing traction and last but not least she must have enough fork spring resistance not to allow the forks to bottom out during maximum braking. Follow these rules, improve your braking skills with practice and you'll be pleasantly surprised how quickly you can burn speed. Your life may one day be hanging in the balance with total dependence on your braking skills.

I'd suggest everyone take time to test their braking skills from whatever speed they intend to ride. At least give the mind a reference point to work from when the need to burn serious speed raises it's ugly head. Also, I bet everyone who does a few braking drills from high speed will be bit more careful about where and when they decide to twist the throttle into the triple digit zone once they are aware of actual stopping distance, then imagine how far you would tumble if you fell down at that speed.

It's been a fun thread. Thanks for playing along!

 

[Busa1166]

150 mph to zero in 3 feet

 

[Mont]

The chart at the link is interesting (well, to me anyways).

To scrub off 40 MPH from 40 to 0 takes 105 feet.

The 140 MPH stopping distance is 974 feet.

The 100 MPH stopping distance is 522 feet.

So, taking the difference in speed (40 MPH), scrubbing off 40 MPH from 140 MPH to 100 MPH takes 452 feet, or over 4 times as long. Something to consider because it only gets more dramatic the faster you go.

Tuf, can you expand a bit on why bottoming the forks affects stopping distance?

 

[TallTom]

The only times I have gone those speeds, was in a situation where emergency braking was not likely to be needed. I didn't get there as fast as the bike was capable of getting me there and when I let off, I had plenty of road ahead of me to simply coast down. When I pick a spot to do 150, I do so with the idea that emergency braking won't be a part of the equation.

More realistically to me is how fast can I brake from 60 or 70 to something a lot less when I get in a tight spot. Or even from 40 when someone pulls out in front of me.

 

[outlawbusa]

.

Tuf, can you expand a bit on why bottoming the forks affects stopping distance?

Let's hear what the pro has to say, but I would think it would be more in the safety of the stopping in that distance than the actual distance itself. It could prolong the stopping distance if you do not have as much control due to lack of suspension action.

 

[Mont]

it would be more in the safety of the stopping in that distance than the actual distance itself. It could prolong the stopping distance if you do not have as much control due to lack of suspension action.

Even loaded completely up, it's still got rebound to work with. In a full on shut it down type stop, you are putting all the weight on the front tire. The guys that are good at it can even make a show out of it. There's plenty of fails on YouTube though It would sure make for an interesting camera angle to put it where it would show the front forks and just see. Personally speaking, mine loads the rear end completely up on launch, so I would suspect it would load the front completely up if I ever got the balls or had the need to do a full out stop. I would be more afraid of the front tire washing out and dumping me than anything else.

 

[Tufbusa]

The only times I have gone those speeds, was in a situation where emergency braking was not likely to be needed. I didn't get there as fast as the bike was capable of getting me there and when I let off, I had plenty of road ahead of me to simply coast down. When I pick a spot to do 150, I do so with the idea that emergency braking won't be a part of the equation.

More realistically to me is how fast can I brake from 60 or 70 to something a lot less when I get in a tight spot. Or even from 40 when someone pulls out in front of me.

You are a wise man to pick and choose where and when you get your high speed jollies off. However, just like crashes, you don't get to pick and choose when you need more skill than you have. This is why its so important to develop good sound braking skills. Practice stopping from whatever speed. Start out gingerly and work up from there. No one would expect a full on power stop from high speed the very first time. With practice your skill level will increase and your confidence on the brakes will soar! Give it a try Tom. I think you'll enjoy the journey once you begin. And, how bout some photos when you reach the point you can lift the rear with confidence.

Personally, I practice quick stops on most every ride. I have worked so much on braking that my right forearm is an inch larger than my left.

 

[StrtRac3r]

Even loaded completely up, it's still got rebound to work with. In a full on shut it down type stop, you are putting all the weight on the front tire. The guys that are good at it can even make a show out of it. There's plenty of fails on YouTube though It would sure make for an interesting camera angle to put it where it would show the front forks and just see. Personally speaking, mine loads the rear end completely up on launch, so I would suspect it would load the front completely up if I ever got the balls or had the need to do a full out stop. I would be more afraid of the front tire washing out and dumping me than anything else.

I have a camera angle showing the forks... Pretty cool to see all the movement. Here's the view.



Well maybe not the forks... But you sure see the body movement over the wheel.

 

[skydivr]

The chart at the link is interesting (well, to me anyways).

To scrub off 40 MPH from 40 to 0 takes 105 feet.

The 140 MPH stopping distance is 974 feet.

The 100 MPH stopping distance is 522 feet.

So, taking the difference in speed (40 MPH), scrubbing off 40 MPH from 140 MPH to 100 MPH takes 452 feet, or over 4 times as long. Something to consider because it only gets more dramatic the faster you go.

Tuf, can you expand a bit on why bottoming the forks affects stopping distance?

I would suggest: Your forks help the tire work it's very best to grip/stop, and absorb the bumps that are inherent in any braking surface. As your tire reaches max load, anything that takes it over that 'point' means the tire stops gripping (and you crash). The shock helps the tire not hit that 'overload point' by absorbing that 'bump'. Once your forks are fully bottomed out, there's nothing left in the shock to help absorb that bump; ergo: you overload the tire, and off you go...

 

[TallTom]

OK and how would you propose I get a picture of my rear end off the ground while I am doing this?

In all seriousness I have got my rear end "light" probably 6 times. And I do routinely practice my emergency stopping scenarios. I have gotten comfortable with finding that edge where I just get that point between lock-up and just before. It sometimes requires feathering the lever on and off, but you definitely build confidence by practice. I also practice 2 -Up as that changes everything.

My goal is not to lift the rear off the ground. I want as much tire contact as possible when braking. I know the rear is only about 30% of my braking power, but in an emergency braking situation, that extra 30%.............