Importance of surprise horizon

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jcochrane
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Importance of surprise horizon

Postby jcochrane » Mon Apr 05, 2021 11:32 pm

Video of my drive the other day. Excuse the "bloody hell" and "Gordon Bennett" Normally I don't make exclamations. Speed limit for road 40mph. How would I have faired if on a motor bike?

Brings home the importance of the surprise horizon and using that to adjust speed so you can stop comfortably on the tarmac available, (builds in a safety margin for these situations).

https://youtu.be/Gn8NcKWt2cw

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dvenman
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Re: Importance of surprise horizon

Postby dvenman » Tue Apr 06, 2021 6:50 am

I think on a bike you'd have been safer, as you had room nearside to move into, and the speed seemed reasonable to the circumstances.

I had a similar situation on a right hander in Scotland while learning left foot braking in an auto. Funny how quickly the car stops with both feet on the brake pedal!

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GTR1400MAN
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Re: Importance of surprise horizon

Postby GTR1400MAN » Tue Apr 06, 2021 7:52 am

Good example, though not sure there's any difference between 'surprise horizon' and 'limit point' at that time.

Nice bridge/viaduct. :)

On the bike I'd **probably** have been a little wider than where your drivers seat is positioned, but then I would have seen it a bit earlier. Being slim :lol: we can get through in a lot of these situations where a head on can result in a car.

Sadly this sort of driving is more and more common, cutting corners with no visibility (as opposed to straightening with an excellent view ;) )

Here's a right hander where I had to squeeze through (I'm the rider in front of the camera bike)

Mike Roberts - Now riding a Triumph Explorer XRT. My username comes from my 50K miles on a Kawasaki 1400GTR, after many years on Hondas of various shapes and styles. - https://tinyurl.com/mikerobertsonyoutube

martine
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Re: Importance of surprise horizon

Postby martine » Tue Apr 06, 2021 9:19 am

Nice drive John - and good reactions.

I couldn't see the oncoming driver - do you reckon they were distracted perhaps on a phone or just very badly positioned?
Martin - Bristol IAM: IMI National Observer, Group Secretary, Masters (dist), DSA: ADI, Fleet, RoSPA (Dip)

janetwise-griggs
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Location: Near Caterham

Re: Importance of surprise horizon

Postby janetwise-griggs » Tue Apr 06, 2021 11:45 am

It's an SUV, typical driving style for around here I'm afraid. That piece of road runs past Woldingham Railway Station towards Caterham.

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jcochrane
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Re: Importance of surprise horizon

Postby jcochrane » Tue Apr 06, 2021 12:51 pm

martine wrote:Nice drive John - and good reactions.

I couldn't see the oncoming driver - do you reckon they were distracted perhaps on a phone or just very badly positioned?


Hi Martin. No chance of seeing the driver. I was more focused on the front of the car hoping it would move back on side. Can't tell from the video either or read the number plate.

It is possible they turned right from the single track lane just passed the bridge. The track leads to a school. I'm pretty sure when I glanced in the mirror the car was still in the middle of the road and appeared to be just starting to move back to my side of the road (but I might be wrong). The driver may have been a foreigner who had visited the school and had a moments laps of attention when turning onto the main road.

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GTR1400MAN
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Re: Importance of surprise horizon

Postby GTR1400MAN » Tue Apr 06, 2021 1:40 pm

jcochrane wrote:It is possible they turned right from the single track lane just passed the bridge. The track leads to a school. I'm pretty sure when I glanced in the mirror the car was still in the middle of the road and appeared to be just starting to move back to my side of the road (but I might be wrong). The driver may have been a foreigner who had visited the school and had a moments laps of attention when turning onto the main road.

I had great trouble finding the road/bridge via the GPS co-ordinates displayed 51°17'46.5"N 0°03'35.9"E

When I changed the Easting to a Westing all was good. Very strange.
Mike Roberts - Now riding a Triumph Explorer XRT. My username comes from my 50K miles on a Kawasaki 1400GTR, after many years on Hondas of various shapes and styles. - https://tinyurl.com/mikerobertsonyoutube

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jcochrane
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Re: Importance of surprise horizon

Postby jcochrane » Tue Apr 06, 2021 2:52 pm

GTR1400MAN wrote:
jcochrane wrote:It is possible they turned right from the single track lane just passed the bridge. The track leads to a school. I'm pretty sure when I glanced in the mirror the car was still in the middle of the road and appeared to be just starting to move back to my side of the road (but I might be wrong). The driver may have been a foreigner who had visited the school and had a moments laps of attention when turning onto the main road.

I had great trouble finding the road/bridge via the GPS co-ordinates displayed 51°17'46.5"N 0°03'35.9"E

When I changed the Easting to a Westing all was good. Very strange.

That's interesting. I live almost on the Greenwich Line and the road in question is definitely west of me.

waremark
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Re: Importance of surprise horizon

Postby waremark » Tue Apr 06, 2021 9:59 pm

jcochrane wrote:Video of my drive the other day. Excuse the "bloody hell" and "Gordon Bennett" Normally I don't make exclamations. Speed limit for road 40mph. How would I have faired if on a motor bike?

Brings home the importance of the surprise horizon and using that to adjust speed so you can stop comfortably on the tarmac available, (builds in a safety margin for these situations).

https://youtu.be/Gn8NcKWt2cw


Good reactions John, and prudent speed, you should be proud

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jcochrane
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Location: Surrey-Kent borders and wherever good driving roads are.

Re: Importance of surprise horizon

Postby jcochrane » Tue Apr 06, 2021 10:08 pm

waremark wrote:
jcochrane wrote:Video of my drive the other day. Excuse the "bloody hell" and "Gordon Bennett" Normally I don't make exclamations. Speed limit for road 40mph. How would I have faired if on a motor bike?

Brings home the importance of the surprise horizon and using that to adjust speed so you can stop comfortably on the tarmac available, (builds in a safety margin for these situations).

https://youtu.be/Gn8NcKWt2cw


Good reactions John, and prudent speed, you should be proud


Very kind Mark, thank you. I think I feel grateful more than anything else.


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