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Visual Focus And Cornering


Crash106

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I was wondering about speed and vision and how close is too close in terms of watching the road in front of the bike. I decided to do some math and find out. Here is what I learned.

 

  1. Average reaction time = 0.20 seconds
  2. Average time to lean a bike (or get on the brakes) - 1.00 second
  3. Total time to react and start turning or stopping the bike = 1.20 seconds

  • At 40 mph, distance traveled in 1.20 seconds = 70 feet (or 10 bike lengths)
  • At 60 mph, distance traveled in 1.20 seconds = 106 feet (or 16 bike lengths)

 

So, if my calculations are correct (please double check), then there is little reason to look at ANYTHING closer than 10 bike length in front of the motorcycle when riding at 40 mph or faster. Even if the road literally ends and drops off into a canyon, we will barely have time to start braking or turning before we sail off into infinity.

 

On the other hand, by looking MORE than 10 bikes length out, we are more likely to see signs of trouble--cars disappearing over the edge of the bridge, a guy waving his coat, brakes lights or whatever.

 

Today, after work, I'm going out to the parking lot to pace off 70 feet and 106 feet. Just so I can see how far out I need to keep my focus. Do you agree or disagree?

 

Crash106

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Funny you would bring this up...

 

I was thinking about illusions of depth perception. I noticed the other day that as I was really far away from the corner (I was in my car this time), that I felt I was going to fast for the upcoming corner and got on the brake. As I got nearer the corner I clearly could see that I was waaaay wrong and got on the gas.

 

What causes these vision/ speed/ timing errors? I sure this is discussed somewhere in T2, but my copy is in storage right now.

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I was thinking about the two step. Before the school I had just gotten to the point where I would start looking into the corner about 10 feet before hitting my TP. Going from 10 feet vision, moving fast, to wide view looking through the corner, I noticed that I had scrubbed off a lot of speed. I was going way too slow. Now I'm having the problem that I turn the bike, I'm still going too slow, but I just found out, thanks to Matt, that it's early braking (something the CSS doesn't work to correct), and that's something I have to work on. I'm sure I'd do better if Stu came out and I could follow him around Inde all day, but for now I've got to work it out.

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.... there is little reason to look at ANYTHING closer than 10 bike lengths in front of the motorcycle when riding at 40 mph or faster.

 

Crash,

 

Taking that thought to an extreme, how would it feel riding at 40 mph with some kind of optical device that meant you couldn't see anything closer than 10 bike lengths? I'm not sure I'd want to try that!

 

Muppet

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Muppett,

 

You asked, "How would it feel riding at 40 mph with some kind of optical device that meant you couldn't see anything closer than 10 bike lengths? I'm not sure I'd want to try that!" Good point.

 

I recently read a review of the Victory Cross Roads and Cross Country. The writer preferred riding the Cross Roads with the clear plexi-fairing over the Cross Country with the large, handlebar mounted fiberglass fairing. He said, being able to see the road under his feet gave him a greater sense of agility. That feeling is an important part of our riding pleasure.

 

On my bike, I have a clear view over the windshield at about 40 feet in front of my bike. At anything over 30 mph, if I see something THROUGH the windshield, I can barely make the bike start to wiggle before I'm on top of the object. Since we are all human, our vision WANTS to get caught on stuff. Perhaps the trick is to learn to catch-and-release these "visual magnets."

 

Crash106

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Very interesting post crash. Now I have to go out and pace off 106 feet to see for myself how far that really is.

 

I think having something that blocked any portion of your vision would make you feel very uncomfortable.

 

The point isn't what you see though, it is where you have your attention. The trick is to ignore the stuff close to the bike and have you attention on what is up ahead. On the track you still want to use your peripheral vision to track your apex, but your attention should probably be on your vanishing point :) On the street, you can use your peripheral vision to keep track of the center line of the edge of the road while keeping you attention further up ahead.

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While I generally agree with the premise you have put forth, I think there are still some things you can do within that short time to react to things you might only see within that short distance. For example, a surface irregularity, such as fine grain gravel of similar color as the pavement, it might not be visible until you are very near it. And within that short time before you get to it you could: brake for a moment, get from off-throttle to on-throttle for stability, or steer the front tire around an obstacle. You won't change your direction by much but just getting from off to on throttle can be a real help in a lot of circumstances involving sketchy surfaces on public roads.

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While I generally agree with the premise you have put forth, I think there are still some things you can do within that short time to react to things you might only see within that short distance. For example, a surface irregularity, such as fine grain gravel of similar color as the pavement, it might not be visible until you are very near it. And within that short time before you get to it you could: brake for a moment, get from off-throttle to on-throttle for stability, or steer the front tire around an obstacle. You won't change your direction by much but just getting from off to on throttle can be a real help in a lot of circumstances involving sketchy surfaces on public roads.

 

 

I think what the OP is saying is that even if you saw something that close, by the time you reacted (got your fingers to the brake, or even just pulled in in if they were already there) you would have already gone past what you saw.

 

I think the question is how long does it really take you to react. In the OP he states it is 1.2 seconds, does it really take that long to grab the brake?

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There is such a device that can be used to restrict vision. I've used a Vision Limiting Device (foggles) during instrument flight training. There is also a device affectionately called a 'hood'. Yes, it affects you more emotionally than anything else.

 

So how does one train himself to look at only what's important and pay less attention to distractions? Not really practical on the street, but can pay dividends on the track.

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During flight training the hood has a side effect of emotional stress, our vision is limited to watching the instruments telling us (often) the opposite of what our body is telling us. This is a limitation to the parallel we could draw to what we do on the motorcyle, so thankfully there a way of answering your question without duct taping your visor (as interesting that'd be for spectators :)).

 

Jaybird180 said:
"So how does one train himself to look at only what's important and pay less attention to distractions? Not really practical on the street, but can pay dividends on the track."

If the rider were to do a ride (in a safe environment such as a trackday), where their riding plan was to focus on the "distractions", keeping their vision down, then the next session alter their riding plan to ignore the distractions (that we can't control), use reference points and three step (ask if you dont know what that is!) to get attention where it needs to be, then would this give them a very clear example of how their riding would be impacted?

 

Would this assist them in making a concious decision in future to focus on what is important.

 

In other words for riders reading this who would like an answer, the answer may be staring at you, but until you convince yourself by way of trying the method that doesn't work versus the method that works, then no amount of text on a forum, independant of the writer will override your SR's when you need it most - convince yourself and you have it on good authority to do what works when you really need it!

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While I generally agree with the premise you have put forth, I think there are still some things you can do within that short time to react to things you might only see within that short distance. For example, a surface irregularity, such as fine grain gravel of similar color as the pavement, it might not be visible until you are very near it. And within that short time before you get to it you could: brake for a moment, get from off-throttle to on-throttle for stability, or steer the front tire around an obstacle. You won't change your direction by much but just getting from off to on throttle can be a real help in a lot of circumstances involving sketchy surfaces on public roads.

 

 

I think what the OP is saying is that even if you saw something that close, by the time you reacted (got your fingers to the brake, or even just pulled in in if they were already there) you would have already gone past what you saw.

 

I think the question is how long does it really take you to react. In the OP he states it is 1.2 seconds, does it really take that long to grab the brake?

 

1. Average reaction time = 0.20 seconds (from OP)

OK seems reasonable.

 

2. Average time to lean a bike (or get on the brakes) - 1.00 second

Some people can lean it a lot faster I think.

 

3. Total time to react and start turning or stopping the bike = 1.20 seconds

Just because it took somebody 1.0 second to lean a bike doesn't mean it takes 1 second to pull the brake lever, twist the throttle slightly, or steer the tires around an obstacle.

 

I can think of a lot of cases where I reacted to something that seemed quite closer than 70 or 100 feet at 40 to 60 mph. Hell the bike is so damned maneuverable at those slower speeds. However, while many of us may be a good judge of distance in a practical working sense, and know what we can react to at any given speed based on a lot of previous experience, I doubt myself or most other riders are that great at asigning actual numbers to it like specific feet or seconds. I can walk into a room and tell you off-hand if it is 10 feet wide or 12, but in outdoor environments plus moving at speed, it's a much different story. In outdoor environments I typically way underestimate horizontal distances.

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Try to ride towards a manhole at 40 mph and see how close you can get before swerving to avoid it. I think you will be surprised how close you can get, probably around 20 ft. It will depend heavily upon the bike and the amount of power you use on the handlebars - a chopper will take ages, a nimble 200 lb machine can turn on a dime.

 

I do this all the time when riding on city streets I wait until the last possible moment before swerving to avoid manholes, potholes etc. Not only will it make you more confident when it comes to excerting a lot of force to the handlebars, it will also make it more likely that you will countersteer in an emergency situation. Finally, following cars tend to keep a very safe distance because from their view you look like a lunatic :)

 

When driving and riding on the road, I try to look past all other traffic as if it wasn't there, seeing as far forward as possible. The worst you can do is look directly at the car in front. You just need to be aware of it at all times, not stare at it.

 

However, when I ride I constantly switch my view between far ahead and real close - I do not want to hit holes or bumps or paint or anything else that can upset the bike. Looking far ahead is great on a race track where the conditions are known, but limiting yourself to the wide view on public roads is not something I would recommend.

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Harniois, Eirik and All

 

I think you are correct that we CAN react to, swerve around or break for things closer than I originally stated. After all, I think I'm on pretty solid ground to say we've all turned into a corner, then leaned the bike over More at, or just before, the apex. Clearly, we're reacting to that approaching reference point. But I'm not sure focusing on a planned reference point is the same as seeing, comprehending and reaction to an unplanned patch of sand or oil.

 

I've certainly been calmer on the bike since I started scanning the road surface as I approach a corner, then making a commitment to standard throttle control (if that is appropriate in that corner). I feel I am riding smoother and safer by NOT trying to react to every little thing I see. That's what I was trying to get at.

 

Thanks to everyone for a great discussion.

 

Best wishes,

Crash106

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An interesting discussion for sure. One thing that hasn't been talked about much was having a wide view, starting from the approach to a turn. How would this effect the whole visual situation?

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The wide view, as I tried to explain in my own way earlier, makes things slow down dramatically more often than not. You will run a smaller risk of getting surprised by other traffic, obstacles, change of road direction etc. However, as I also mentioned, relying solely on the wide view on public roads is - IMO - a bad idea because it will obscure things like small patches of sand, oil, bumps and dips etc since the peripheral vision isn't sharp enough to notice them, nor are they always visibile from a distance. Hence road riding demands - IMO - a constant alternation between the wide view and glances on the road quite close to the bike. Eyes must move constantly. On a track, with a known surface, scanning the road is of less importance and keeping things "slow" is of greater importance.

 

At least that's my take on it :)

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The wide view, as I tried to explain in my own way earlier, makes things slow down dramatically more often than not. You will run a smaller risk of getting surprised by other traffic, obstacles, change of road direction etc. However, as I also mentioned, relying solely on the wide view on public roads is - IMO - a bad idea because it will obscure things like small patches of sand, oil, bumps and dips etc since the peripheral vision isn't sharp enough to notice them, nor are they always visibile from a distance. Hence road riding demands - IMO - a constant alternation between the wide view and glances on the road quite close to the bike. Eyes must move constantly. On a track, with a known surface, scanning the road is of less importance and keeping things "slow" is of greater importance.

 

At least that's my take on it :)

 

There is a bit more information on the VW as it is covered in the classrooms currently. Not trying to be secretive, but I can't put it down in a few works all the pieces that Keith (or Dylan/Stuman) go over in the briefings.

 

I'll say one thing: if one could keep enough space out in front, and still keep track of tihngs that happen closer in, would that be an ideal situation?

 

CF

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I'll say one thing: if one could keep enough space out in front, and still keep track of tihngs that happen closer in, would that be an ideal situation?

 

CF

 

 

Most definitely. If you have a way to do that without constantly moving your focus point from close to near to close to - you get it - I'd be highly interested. Because I can only see details within a very narrow "window". For instance, keeping the VW I cannot even make out anything from the instruments or mirrors. I do notice that they are there, but I do not have enough details in the information that I can use it for anything, no matter how hard I try to focus (cannot make out the point needles or whether there is a car etc. in the mirrors, it's all just a blur). Same with minor stuff in the road.

 

Just after the snow went a few weeks back, I made a walk in the park keeping the VW all the time. Very cool to observe birds in the sky while not looking at them, etc. I also stepped in lots of dog turd because I couldn't make it out from the gravel and mud :unsure: Shifting my view from near to far constantly saves my shoes :lol:

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I feel I am riding smoother and safer by NOT trying to react to every little thing I see. That's what I was trying to get at.

 

Definitely. With good throttle control and a loose grip, the bike adjusts and stabilizes on it's own and this is something I've come to realize thanks to the superbike school. Unless riding at crazy lean angles, it takes a severe and sustained loss of grip or a collision with a fairly large object to bring it down - a good reason not to ride with severe lean angles on public roads, and to learn good throttle control and a loose grip! However, on the brakes or off throttle and leaned over it can go down real quick on a slick spot, so those are the moments to have the most concern with surface details. And when I think about my visual habits on public roads, I tend to pay a lot of attention to the surface condition as I enter a turn, when I'm off throttle or braking and not yet turned in (but maybe still on a somewhat curved path). Once I turn in and get on throttle my attention moves up around the turn. On the track it's much different, there is really no time when I'm paying much attention to surface details - on turn entry I'm looking ahead to the apex.

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Just after the snow went a few weeks back, I made a walk in the park keeping the VW all the time. Very cool to observe birds in the sky while not looking at them, etc. I also stepped in lots of dog turd because I couldn't make it out from the gravel and mud :unsure: Shifting my view from near to far constantly saves my shoes :lol:

 

Recently, I see an experiment on how the eye sees things in motion. Try this, place your right thumb pointing up in front of you at arm's length while you are looking in its direction but focus far behind it (in wide view). Keep your eye direction and focus unchanged, but swing your arm slowly in a an arc to the right until you cannot see the thumb because it is just out of peripheral vision. At this position, hook and unhook your thumb and now (in wide view) you will see the thumb is moving but you cannot see it earlier when it is not hooking. Some how our eyes can see things in motion better than in static. No wonder with wide view, you can see the bird in the sky while stepping on the dog turd--me too. :lol:

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Perhaps I didn't get it, but yes, I clearly understood that I could better make out the thumb when it was moving than static.

 

 

When I was in Marine Corps marksmanship training, I learned that the human eye cannot focus on 2 objects at varying distances with sharp focus simultaneously. As the thumb experiment above, this applies to a static target and hopefully static gun sights (LOL).

 

When we ride, NOTHING is static except for our view of the tank, windscreen, gauge cluster, etc. So if we're looking at these things, it is not possible to also have the eye/brain process the view of the road ahead.

 

Focus your attention on the patch of dirt and the moving objects blur.

 

So, Cobie...spill the beans man. What's the new concepts on vision?

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Perhaps I didn't get it, but yes, I clearly understood that I could better make out the thumb when it was moving than static.

 

 

When I was in Marine Corps marksmanship training, I learned that the human eye cannot focus on 2 objects at varying distances with sharp focus simultaneously. As the thumb experiment above, this applies to a static target and hopefully static gun sights (LOL).

 

When we ride, NOTHING is static except for our view of the tank, windscreen, gauge cluster, etc. So if we're looking at these things, it is not possible to also have the eye/brain process the view of the road ahead.

 

Focus your attention on the patch of dirt and the moving objects blur.

 

So, Cobie...spill the beans man. What's the new concepts on vision?

 

Vision...this really is one of the big issues in riding. I think the Level 2 material is the most often re-viewed, clarified, learned again (at a great pace, the game changes), of all our material. New concepts---not sure what we have that would be dramtically new to you JB, but one can tell exactly what a rider is looking at and where his attention is going by riding behind.

 

Ever see a rider go through a turn/series of turns, not going really fast, and then gas it hard when comes out? You can tell the exact moment that he looks up and gets more space!

 

CF

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