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 I need some help with an explanation
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James R. Davis
Male Administrator
17362 Posts
[Mentor]


Houston, TX
USA

Honda

GoldWing 1500

Posted - 07/26/2020 :  4:15 PM Follow poster on Twitter  Join poster on Facebook as Friend                        Like
I haven't ridden a bicycle in over 20 years. On the other hand I was a newspaper delivery boy 60+ years ago and I rode bicycles proficiently.

Where is this going? Well, I recently had another of those chats with a defense attorney who knew nothing about motorcycles and who needed to understand why his client could not successfully manage a large sweeping left turn and nearly died after running into the guardrail. Yep, a lesson about counter-steering was provided.

He almost bought it, but then said that he rides bicycles and can CERTAINLY steer simply by leaning - no hands needed. I confirmed that I had done the same, but that I could not do so with a motorcycle if I was travelling at anywhere near 10 MPH.

Here's the thing, I've HEARD OF motorcyclists who CAN steer by leaning - no hands - at speeds above 10 MPH, though I've never actually seen them do it.

Can somebody please explain to me how that's possible?

Eagle Six
New Member
20 Posts


Snowflake, Arizona
USA

Kawasaki

ZX14R

Posted - 07/26/2020 :  5:28 PM
We know that regardless of how the lean is initiated, the lean is what allows the bicycle and motorcycle to turn (motorcycles lean much more than bicycles, but bicycles are normally ridden at slower speeds). To initiate the turn we can do that by the force of counter steering or by weight shifting (which instigates counter steering). The force of counter steering is deliberate, smooth, and precise, as well as the counter steer to recover from a lean/turn.

Weight shifting is only as effective as the weight difference ratio between the load on the bicycle/motorcycle and the weight of the bicycle/motorcycle. So, the heavier the rider and the lighter the motorcycle, the more effective is weight shifting. The weight of a rider as compared to a bicycle is considerably more than that in comparison to most motorcycles, so it is reasonable we would be able to steer a bicycle easier and more effective by shifting out weight. Also the bicycle is normally traveling at slower speed, so there is more time to adjust for the turn in the road for more turn precision.

I'm 150# geared, and with that weight it is easy for me to shift my weight on a 20# bicycle to throw the weight off axis and initiate a turn, which also induces counter steering to go around a common sweeper at 20 mph.

That same sweeper would be marked 55 mph. My motorcycle weighs in at 540 pounds. Unlike me being heavier than my bicycle, I'm far lighter than my motorcycle and I can hang off as far as possible and get it to start a turn, but not enough turn to negotiate a sweeper and keep my speed at 55 mph. So the motorcycle will turn but I will run off as my the turn radius is not enough to equal that of the sweeper.

The No B.S. motorcycle designed by Keith Code and used at the California Superbike School provide a good example of the limited use of weight shift steering/body shifting and there is a very good video on Youtube showing a demonstration.

We also know that dirt bike riders used weight shifting to a greater effect than street bikes. One the tire contact has less traction so it can be effective more by shifting weight and brute force of the rider, and by comparison to my street bike a dirt bikes comes in around 250#. This supports the issue that weight shifting/body shifting steering if more effective the lighter the motorcycle.

Not sure is this is what you want because I know you know all this, and I know you can put it in a better argument than I, as well as, work out the weight ratio math for comparison.

Although I don't have any proof, I would make two additional arguments.

1. If we setup a video camera to record a bicyclist oncoming, hands off the bars, and body shift to steer (thereby missing the camera), when the video was put into slow motion a counter steer would be detected.

2. It is a lot easier to body shift a motorcycle (although not very effective) into a turn, than it is to body shift out of that same turn.

I would make one more argument.....the average motorcyclist could not explain the dynamics, differences, and/or effectiveness between counter steering and weight/body shifting. Not that this would have anything to do with the explanation you are preparing for the attorney.
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James R. Davis
Male Administrator
17362 Posts
[Mentor]


Houston, TX
USA

Honda

GoldWing 1500

Posted - 07/26/2020 :  5:52 PM Follow poster on Twitter  Join poster on Facebook as Friend  
"It is a lot easier to body shift a motorcycle (although not very effective) into a turn, than it is to body shift out of that same turn."

Thanks. I agree with all that you said. I can visualize a body lean that causes a very slight outracking of the front wheel and thus starting a countersteer. My problem comes with trying to visualize how body lean can compare to the ENORMOUS lean dynamic that instantly begins as the motorcycle starts a turn. My sense is that from that point forward the rider is just that - along for the ride.

And coming out of that turn remains a mystery to me as is anybody's ability to turn in anything but a slight manner. Maybe I'm just thinking of the 'thoughtless ease' I had with my bicycle and can't quite get my head around avoiding the very simple effort of countersteering. Further, I can't remember ever even trying (or having heard of) countersteering during my bicycling days.
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scottrnelson
Advanced Member
6937 Posts
[Mentor]


Meridian, ID
USA

Honda

XR650L, 790 Adv R

Posted - 07/27/2020 :  9:35 AM
More than 100 years ago Wilbur Wright wrote a paper about bicycle steering and used the term "out-tracking" rather than counter steering. It's roughly the same thing except that when I think of it that way it remains consistent in my head at all speeds, super slow to fast.

As for the lean to turn idea, one of the motorcycle track instructors who has written a book on the subject, Keith Code, or Lee Parks, or one of those, had a motorcycle with two sets of bars. The normal bars and a set that has another throttle, but was fixed and not connected in any way to the steering. He used it to prove to those who felt that they could steer just by leaning and weighting foot pegs that they needed counter steer inputs on the bars too. I've talked to a guy who could kind of steer the thing, but he said that it took big body motions to get it to turn much at all.

Just found an article on the subject, not going to toss out what I've written, though. It's Keith Code's No BS Bike (No Body Steer). Here's an article about it: https://soundrider.com/archive/safe...obsbike.aspx
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scottrnelson
Advanced Member
6937 Posts
[Mentor]


Meridian, ID
USA

Honda

XR650L, 790 Adv R

Posted - 07/27/2020 :  9:58 AM
Now that I've read all of the posts...

I would be tempted to get on one of my mountain bikes and experiment, but both of them are unstable with my hands off of the bars. I could ride no hands on all of the previous bikes I've owned, but not on either of these two.

I can remember as a kid riding a tandem bicycle alone from the back seat for several blocks in front of my house. I'm sure I had to reach forward to stop or turn it around, but I had enough control to keep it where I wanted on the road. That would have been accomplished by body motions only.

As for body steering on dirt bikes, I ride on dirt roads at least once a week currently on my two bikes. When I get in a sandy section where steering doesn't do much, I'll stand up and influence the path of the motorcycle by leaning it using the grip of my knees on the tank. That allows me to alter the path by about six inches more than just steering would allow me to do. This is while going 20-30 mph. The front wheel otherwise just slides when trying to steer much at all in deep sand or silt. Standing up and leaning the bike one way or the other also helps on rough rocky sections. It definitely still needs counter steering, but moving the body around helps quite a bit.
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Eagle Six
New Member
20 Posts


Snowflake, Arizona
USA

Kawasaki

ZX14R

Posted - 07/27/2020 :  11:36 AM
quote:
Originally posted by James R. Davis

And coming out of that turn remains a mystery to me as is anybody's ability to turn in anything but a slight manner. Maybe I'm just thinking of the 'thoughtless ease' I had with my bicycle and can't quite get my head around avoiding the very simple effort of countersteering. Further, I can't remember ever even trying (or having heard of) countersteering during my bicycling days.



I remember once viewing a Youtube video of a rider, on I think it was a Harley sportster, with no hands on the bars and weight shifting through turns. The road was down hill and each turn had a healthy positive camber (which aided turning without much lean). He was doing it staying in his lane, but his lines were terrible and his body shifting was extreme.

I don't remember exactly when I first heard the term counter steering, but it was a long, long time ago and I do remember saying, yea that's what I do and thought counter steering was a silly term for it, because I thought of it as normal steering!!

We know the rake and trail of normal motorcycle design creates a geometry that is both stable in a straight line and easy to turn. The less rake/trail the more it wants to induce counter steering to aid in leaning the motorcycle for turning anytime the motorcycle gets even a slight amount off straight up and down. That makes steering easy with little effort and many riders still believe it is them making the motorcycle turn by loading weight on the pegs! That along with, at speed it takes very little movement of the bars to induce lean, so it is not very noticeable.

Despite we have more basic riding training available in all states now, there are still many riders graduating from these classes that have a very minimum to no understanding of counter steering! It's covered, but in my opinion not enough that new riders can use it for the safety of their riding, like running off the road in turns. That to me is sad that the industry that gains the most from creating safe riders is doing only the minimum. This is my opinion and I'm sure others may disagree.
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James R. Davis
Male Administrator
17362 Posts
[Mentor]


Houston, TX
USA

Honda

GoldWing 1500

Posted - 07/27/2020 :  12:01 PM Follow poster on Twitter  Join poster on Facebook as Friend  
LOL - I've been saying that for DECADES!

I mean that the MSF has known for decades that the most frequent and predictable range injury occurs when students drop their bikes. Legs, knees, elbows and shoulders. Yet they REFUSE to teach students how to dismount a falling bike!

(Stand on the high peg, LET GO of the low grip, and step away from the bike. How tough is that?)
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Eagle Six
New Member
20 Posts


Snowflake, Arizona
USA

Kawasaki

ZX14R

Posted - 07/27/2020 :  6:19 PM
Also, the MSF and the state test stress if you drop the bike you fail, so students attempt to save it!

Pretty much there are those of us who have, those who will, and a few of us like me, that will again, drop a bike. Get of without injury and it a valuable lesson you can laugh at. Get off with an injury and it's a lesson we can dry over.

I agree, it just doesn't make any sense to down grade a rider for dropping their bike, nor teach them safely how to dismount and let it go!
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JanK
Male Junior Member
89 Posts


Ljubljana, Ljubljana
Slovenia

BMW

R1200R

Posted - 07/29/2020 :  10:46 AM
The way that hands-off steering works on my motorcycle is that I lean the body into the (let's say left) turn then press with the left foot on the footpeg and simultaneously press with the right knee into the tank. To be honest, I'm still not clear about the physics behind this technique, but it can be surprisingly effective.

Here's a video https://youtu.be/jtyuT-vYQhA of hands-off slalom between cones set 9 metres apart (as described in section 3.1.2.4. on page 7 of https://www.uradni-list.si/files/RS...007-0000.PDF. The speed was around 30km/h, but I could not make a turn around each cone, so the slalom was around cones effectively set 18 metres apart.

I also tried taking a corner at https://www.google.com/maps/@46.026...ata=!3m1!1e3. The video is at https://youtu.be/mgF4uPxH7-4. The second turn at https://www.google.com/maps/@46.025...ata=!3m1!1e3 was too sharp and I could not make it without using the handlebar.
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Eagle Six
New Member
20 Posts


Snowflake, Arizona
USA

Kawasaki

ZX14R

Posted - 07/29/2020 :  11:33 AM
quote:
Originally posted by JanK

The way that hands-off steering works on my motorcycle is that I lean the body into the (let's say left) turn then press with the left foot on the footpeg and simultaneously press with the right knee into the tank. To be honest, I'm still not clear about the physics behind this technique, but it can be surprisingly effective.

Here's a video https://youtu.be/jtyuT-vYQhA of hands-off slalom between cones set 9 metres apart (as described in section 3.1.2.4. on page 7 of https://www.uradni-list.si/files/RS...007-0000.PDF. The speed was around 30km/h, but I could not make a turn around each cone, so the slalom was around cones effectively set 18 metres apart.

I also tried taking a corner at https://www.google.com/maps/@46.026...ata=!3m1!1e3. The video is at https://youtu.be/mgF4uPxH7-4. The second turn at https://www.google.com/maps/@46.025...ata=!3m1!1e3 was too sharp and I could not make it without using the handlebar.



It's good that you took your time to video and post the findings. Your results are not surprising, that is about what I can do on my motorcycle, which is far from controlled through the cones or adequate for street riding.
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