The Vanishing Point

[DataDan]

2) When used correctly, the VP technique will have you holding a line at the outside of the turn with deceleration until the VP distance goes steady, at which point you should be in more of a maintenance throttle mode, and then when you see the VP start to get further away, commit to a lean angle and roll on.

Please let me know if I seem to have gotten the gist of it.

Correct. When the VP is staying at a constant distance, you're approaching a constant-radius section of turn. At that point, you steer and begin to roll-on the gas.

See the last pic in the photo sequence, the aerial with sightlines drawn in, to better understand the relationship between the radius of turn in front of you and the progress of the VP.

 

[budman]

Agreed Andy... good point.. I was comparing throttle off --scrubbing speed-- throttle on would be maintaining as you pointed out or on more.. adding speed.

Very important aspects for the new rider to understand :thumbup

:smoking

 

[Robin]

Good stuff Dan :thumbup
One can also use other objects to further 'read' a corner. Hedgerows, lamp posts, power lines can give you a feel for where the road goes when it becomes blind.

 

[izzy_OCR]

I'd rather not go there.Newbies are often told to use the clutch to slow down when needed.

Hi can you explain this to me "I'd rather not go there.Newbies are often told to use the clutch to slow down when needed."Do you mean, newbies hold the clutch in and to slow down? I've been riding for a couple of years, and there have been time when, I'll be going into a turn too fast; so what I do is, I squeeze the front brakes hard to slow down a little bit then down shift a gear! As a Vet. (I'm guessing) how would you handle this, when you are going to fast into a turn, I know you would want to lean and have a steady line but, what I'm doing is right??

 

[Bumble6ee]

Very useful info, thank you!

 

[sanjuro]

I was reminded about this today on my bicycle commute.

I was headed downhill to a right turn on a tight street. I've could have easily hit the turn doing 20mph but there were a parked SUV blocking my vision.

I slowed down to probably 10mph and instead of making a wide turn which would have put me into the middle of the street, I took an angle closer to 90 and was able to keep the turn tight.

Good thing because a car was driving down the middle of this very tight street, and I was able to squeeze by even though instead half the road, I barely had the width of a bike lane.

If I had gone full speed, I would have ended up in the middle and I would have gone into the windshield.

When I am on my motorcycle, I tend to take all street turns rather cautiously because the variables are much greater than the highway. But the line of sight is the most important factor in navigating the streets.

 

[latindane]

DataDan, the link on your first post sent me to an AT&T net "content blocked" page; would it be possible for you to attach the pics to the thread? I think they would help me visualize the technique...

 

[DataDan]

DataDan, the link on your first post sent me to an AT&T net "content blocked" page; would it be possible for you to attach the pics to the thread? I think they would help me visualize the technique...

Thanks for finding that. The server space I used to have through AT&T is no longer available. Photos now appear in the OP of this thread, inline with the text.

 

[latindane]

Very nice post! Thank you Dan for uploading the pics. I had heard about the vanishing point, but thought it was a way to keep your sight focused far ahead from the (where you want to go). Will give this one a try next time I'm on the road.

Thank you for taking the time to write this kind of posts for the benefit of the rest of us.

 

[DataDan]

Here's a vivid real-world example of how the VP can help you to judge a turn.

The General thread Crash on HW9 this afternoon (3/28/10) - Rider airlifted is about a crash that occurred on a notorious blind, decreasing-radius right-hander. Misjudging the turn, the rider ran wide at the exit and hit an oncoming pickup (not head-on, but at the rear wheel).

If you have Google Earth, you can follow the turn on which the crash occurred from the same point of view the rider had. Go to 20716 California 9, Boulder Creek, CA. The turn is just south of that location (though nominally north, since that's the direction to Skyline), a right-hander marked with a 25mph warning sign. Click one of the street view icons and rotate your view so you're behind the red Corvette. Follow the Vette through the turn, taking note of the distance to the VP.

What do you notice about the progress of the VP through the turn? At what point would you commit to a line?

 

[speedster]

This is a great post. It's a significant step in riding proficiency. Thanks DD.

 

[louemc]

The Vanishing point is only part of it. That's talkin about stuff that isn't moving (isn't it?).

The public road has something else. On-coming vehicles that may not be on their own side of the road. The closing speed...puts even higher demands on how the biker is entering a corner.

 

[tzrider]

The Vanishing point is only part of it. That's talkin about stuff that isn't moving (isn't it?).

This is correct. The usefulness of the vanishing point is in giving the rider the earliest indicator of the configuration of the road immediately ahead. It's clearly not the only factor one should take into account when setting their speed. That said, seeing that a turn is tightening up will allow the rider to slow down for that portion of the turn before he's in it.

 

[flying_hun]

:bump for an awesome topic

 

[kwh]

Well bumped!

And I just posted a video that covers the vanishing point both near the start & in more depth towards the end, in the 'Video & Photo' topic.

See 'The Art of Turning Left' .

 

[afm199]

The Vanishing point is only part of it. That's talkin about stuff that isn't moving (isn't it?).

The public road has something else. On-coming vehicles that may not be on their own side of the road. The closing speed...puts even higher demands on how the biker is entering a corner.

I've been on organized rides where the lead rider cut the yellow at a blind corner and EVERYONE behind followed them. I asked the person in front of me if they felt comfortable doing that, they responded that:" The person in front of me didn't have a problem." God. I turned around and went home. This was a fairly well known organized local ride. Nobody knows what is coming. Poor Joe Montoya found that out the hard way.

 

[Butch]

Good thread. I have always (maybe not always, but certainly in past decades(ouch old)) that should not outrider the road you can see,

The faster you go, the less far you can see. At 60 mph, if it takes you a half second to recognize and react to something, you just traveled 44 feet. That is 44 feet less that you can see ahead.

 

[kwh]

youtu.be/J4EQlCtBS8o

 

[OVerLoRDI]

Awesome approach. Usually you see this with just the above diagram, but having the actual images of the road from "bike level" is extremely cool.

 

[GAJ]

This thread should be required reading for every BARFer with a bike. :thumbup