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Old 11-20-2012, 01:29 PM   #811
Harvey Krumpet
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Quote:
Originally Posted by Vulfy View Post
Well in defense of that, I think he was just proving a point that counter-steering should be the main technique to steer the bike. Body position and weighting, definitely play a part in steering, but they are an addition to counter-steering. As "The twist of the wrist" is a beginner / intermediate riding book/movie, I think he just wants to get the point across that you should use the handle bars to steer your bike, not foot pegs. Aaaanyways....

Back to MotoGymkhana and body positioning on the bike.
Fair call. Doing the exercise brought to mind the scene with the guy trying to steer with the footpegs & gradually moving off line. Combining the two makes a much bigger difference.

In a previous post you mentioned that it sometimes feels as if your hands are fighting against each other. That describes exactly what I feel when doing my full lock 8's through the 1 mtr gate. Technique goes out the window & I end up wrestling with the bars & get tense. It's bizarre, the bike is obviously happy to fall over through the turn so I must be fighting myself to make it turn, half of me is making it run wide the other half fighting against that.

Learning to pop a wheelie might be easier.
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Old 11-20-2012, 01:35 PM   #812
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I can't seem to find the video right now but there was a clip on YouTube from one of Keith Code's videos where he shows a guy with a modified bike proving his point. There is a set of "handlebars" welded to the frame above the real handlebars. Because they are welded to the frame, you can push and pull on those bars all you want without affecting steering. Anyway, Code has the rider hang off the side of the bike while holding on the welded bars, and the bike ends up in the grass on the outside of the corner the rider is trying to negotiate. Do the same with the real handlebars, and the bike darts around the corner of the track as you would expect. Code explains that, when you position your body on the bike, you are in fact pushing and pulling on the handlebars even though you don't realize it, and that pressure on the bars is what initiates the turn. Sure, the bike curves a little with body weight, but not as significantly as I had thought (I've practiced shifting body weight to swerve around obstacles without -- intentionally -- pushing on the bars).

If you think about it, this makes sense. I'm like 170 to 175 pounds bare-*** naked (sorry for that mental image, everyone! ) first thing in the morning, so I'm *maybe* 190 in full leathers and gear; my bike, on the other hand, is probably over 500 pounds all up. Is shifting my C.G. a few inches to the inside of the turn REALLYgoing to affect our combined C.G. very much on a bike that weighs more than 2 1/2 times as much as I do? Sure, it helps, and in gymkhana or on a track, every little bit adds up. However, it seems to me that countersteering, intentionally or otherwise, plays a much more important role than just shifting body weight a few inches.
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Old 11-20-2012, 01:48 PM   #813
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Sure, it helps, and in gymkhana or on a track, every little bit adds up. However, it seems to me that countersteering, intentionally or otherwise, plays a much more important role than just shifting body weight a few inches.
Yup. No question about that. I remember that clip too. What fascinated me doing the evasion maneuver was how much weighting the footrests helped the turn, particularly transitioning from one side to the other to get back into lane, would make bugger all difference without countersteering but together it's epic. My trainer is a clever lad & he builds one technique onto another so we started with normal steering, then went one handed, then we introduced the foot rests still one handed & finally put it all together with both hands on the bars.

An hoo, body position.....
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Old 11-20-2012, 01:57 PM   #814
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Well yes, nobody is contesting counter-steering.

The scene you are describing is from "Twist of the Wrist 2" movie. I have it on my phone actually, I watch it from time to time on a train, when not commuting on my bike.

So yes, that scene basically shows that "body steering" is not efficient enough to move the bike into a turn.

It still affects the bike's direction, but counter-steering is the main mode to control the bike. So that is established and done with.

Additional movement on the bike, simply add TO the counter-steering, be that to tighten the turn, to balance the bike or to increase/decrease lean angle. ALL of that is complimentary to counter-steering.

Harvey: yes, very often I feel frozen on the bars. One hand pushing one way and the other, opposite. It usually happens when I'm going beyond my comfort / skill limit and I tighten on the bars. I am fully aware of it mentally in my head, WHILE doing it, but its extremely hard to get my body to do what my conscious mind wants.

It is bizarre, sort of an out of body experience, where hands are doing what you do NOT want them to do, and you can't do anything about it.
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Old 11-20-2012, 02:15 PM   #815
Harvey Krumpet
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Originally Posted by Vulfy View Post
Harvey: yes, very often I feel frozen on the bars. One hand pushing one way and the other, opposite. It usually happens when I'm going beyond my comfort / skill limit and I tighten on the bars. I am fully aware of it mentally in my head, WHILE doing it, but its extremely hard to get my body to do what my conscious mind wants.

It is bizarre, sort of an out of body experience, where hands are doing what you do NOT want them to do, and you can't do anything about it.
That sums it up perfectly Vulfy. I've chucked my toys out the cot a few times now because of it.

Both my bikes have wide bars & a lot of lock, especially the DT. Sometimes it feels like the front wheel is almost at right angles to the bike. Next time out I'm going to have a look at my body & arm position on full lock and see if I can shed any light on this.
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Old 11-20-2012, 06:05 PM   #816
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Quote:
Originally Posted by Harvey Krumpet View Post
Fair call. Doing the exercise brought to mind the scene with the guy trying to steer with the footpegs & gradually moving off line. Combining the two makes a much bigger difference.

In a previous post you mentioned that it sometimes feels as if your hands are fighting against each other. That describes exactly what I feel when doing my full lock 8's through the 1 mtr gate. Technique goes out the window & I end up wrestling with the bars & get tense. It's bizarre, the bike is obviously happy to fall over through the turn so I must be fighting myself to make it turn, half of me is making it run wide the other half fighting against that.

Learning to pop a wheelie might be easier.
Ok, something is broken here. You're a good rider, set and determined to be great, or better than great... this should -not- feel like a tensing up of limbs and torso!

Are you jamming music ?
Buddies hanging out and watching/laughing/helping ?
Gotta be somewhere in an hour ?

Something is broken! It should start awkward and wobbly, or tense, and leave you loose as a goose and grinning by the end of the practice. If you need to change music to jazz or freaking gull calls, do it ! If you need a pair of tits , find some ! I swear by the end of a practice I'm ready for a hot tub / beer and a snooze. That loose, that relaxed.

Stretching helps at the beginning, maybe yoga ?

I keep thinking about how it feels like I'm killing the course, and (LAUGHING to myhself) how lame and slow the video will look ;-)
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Old 11-21-2012, 03:19 AM   #817
Harvey Krumpet
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It's a weird thing Oh good. I love doing it but it takes me right out of my comfort zone, I've just been riding bikes for years, all of my thought has been about road craft not riding technique. I guess pretty average really. Getting into motogymkhana has really opened my eyes, like a hot fork stabbed into a butt cheek wide.
Scraping a footrest through a constant radius corner at 100kmh is one thing, scraping a footrest at 20kmh with the bars at full lock is off the scale.
You do have a very good point, though. When the DT & i had a wee lie down I was angry & that translated into aggression in my riding. I WAS going to do it! no if's buts or maybes. Thud.
Now that I have reached a stalling point, again, I'm going to have a good look at what I'm doing, where my technique needs practice, body position & awareness of my course. Fighting myself is just about re-training I think. I think it is a case of more practice, getting the co-ordination & balance to be second nature & creeping up on the limits of braking & grip as I get better.
When I get home from a good session I usually let out a loud happy sigh as I open a beer too. No hot tub, though...
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Old 11-21-2012, 03:33 AM   #818
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what do we think, motokhana to music or silence?
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Old 11-21-2012, 04:17 AM   #819
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Can of worms alert!!!

Crikey, I go and have a nice kip and all hell breaks loose! Never mind, the body position/steering question is worthy of study although the subject is vast in scope.

First things first, let's take a look at assisting the steering of the bike by 'weighting' one or other of the footrests.

For all intents and purposes a bike and rider forms a 'closed' weight system and apart from weight loss due to fuel burn, sweating and tyre and brake pad wear, what weight you start out riding is all you have got to play with. (the picky amongst you will notice that I haven't factored in any increase in weight due to G forces, but as G increases/decreases effects all the loaded weight equally it can be ignored for now)

You cannot ADD weight to such a system so to make any change in the balance (CCofG) of the bike any loaded weight has to be moved.

You can put as much 'weight' (pressure) on a footrest as you like, but unless the rest of your body moves, it will have absolutely no effect.

There is a simple experiment you can do to prove this the next time you are out on your bike. Simply ride in a straight line (the bike isn't a sentient being, so it doesn't know whether it is upright or banked over) and keeping the rest of your body still, press as hard as you like on one or other of the footrests and apart from a tendency to lift your butt off the seat, absolutely nothing happens. Repeat the experiment only this time take your feet off the footrests and move your head laterally to one side or the other and hey-presto, the bike starts to turn (albeit slowly) in the same direction.

Making a bike steer requires that the rider displaces the CCofG to one side or the other of a line connecting the two tyre contact patches thus forming an out of balance couple. This can be done in just a few ways which are turning the bars, laterally shifting the CCofG (or having it shifted for you by an external force such as an uneven road or gust of wind) or changing any centripetal forces acting on the bike during a turn by varying the throttle or the brake. Turning the bars has by far the biggest effect on the relative position of the CCofG, but in Moto Gymkhana the other two methods play a crucial role especially at slower speeds.

The steer with one hand method as detailed by Lee Parks certainly has a beneficial effect on our riding because our bikes have a dirty great hinge in the middle which must be allowed to move freely during the steering process. A little acronym that you should remember is FAST or Fear+Anxiety+Stress=Tension. Any tension in our arms and upper body reduces the ability of the bars to move freely and instead acts like a form of crude steering damper which slows the steering rate down. By reducing the fear, anxiety and stress we feel we automatically reduce the tension which improves the steering which helps reduce the fear and so on in a virtuous circle. Steering with one hand goes a long way towards this pleasent state of affairs as it reduces any undesireable forces on the steering by 50%!

To further reduce the undesireable forces acting on the bars, our Japanese friends promote a basic body position of Butt Back, Knees In, Elbows Out and Head Up. With the elbows out there is much less likeleyhood of one or other of your elbows crashing into your upper body as the bars turn. To see what they mean try this experiment whilst sat at your computer. Hold both hands out in front of you as you would if holding the bars and point your elbows down. Now move one of your hands back towards you until your elbow hits your upper body and note the position of your hand. Repeat the experiment only this time stick your elbows up and out and this time you will see that your hand comes much further back towards you than was previously the case. Notice also that with the elbows out the wrists become bent somewhat awkwardly on the grips, so you will need to change the angle of your grip from 90 degrees to about 120 degrees. At this angle the grip no longer lies along the line of your knuckles but follows the creases in your palm instead.

Vulfy wants a discussion on EVERYTHING which is quite a big ask, but it's certainly worthwhile having the discussion as there is a great deal to learn.
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Old 11-21-2012, 08:57 AM   #820
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Quote:
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what do we think, motokhana to music or silence?
usually just ear plugs, sometimes pandora celtic stream, or something else that makes people roll their eyes.

so long as I can smell when the rear brake is about to ignite, my ears don't need much input ;-)
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Old 11-21-2012, 10:21 AM   #821
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As has been mentioned some of the Japanese riders often look out of the rotation turns rather than always looking into and around them.

This was most intriguing for us when we first saw it as the rule is your bike goes where your nose is pointing, so why should anybody want to look out and away from the turn?

We asked several of the riders about this technique and sadly got quite a few different answers, so here is a digest of what we were told.

It's done to 'unwind' any dizziness.

Saves having to lift the chin up a long way to view the horizon and to determine bank angle.

To identify a point on the outside where you would end up if you continued the turn, so you are not breaking the rule.

The head is not being turned out, it's just that the bike has turned away from underneath you. The regular head-snaps help to keep the turn as tight as possible.

Take your pick...

I have tried it and although it is certainly very strange at first it does seem to work.

I found this video of Momoko Tsukihara and Peter Hach (check out his headgear) where you can see two different techniques being used. Momoko snaps her head in the direction she wants to go whilst Peter seems to let the bike turn under him before snapping again. I'll let you be the judge.






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Old 11-21-2012, 10:27 AM   #822
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A group of rider have set up the first gymkhana event for bikes in Malaysia called "Motack" the previous 11th Nov. A total of more than 50 bikes join in various category.
What i can say as a participant is, its an eye opener of how to control your bike while throttling, half clutching, front braking & rear braking all at the same time.

Here's a vid of me tryin the khana.


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Old 11-21-2012, 10:31 AM   #823
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That Katoom sounds oh so sweet! Good job on your first Kone ride!
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Old 11-21-2012, 01:51 PM   #824
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Welcome Raybakh, great to see another Moto Gymkhana group forming to practice the noble art.

You will find lots of useful information in this forum and I hope that it will inspire you to do more. The Moto Gymkhana Association in the UK holds a remit from the Japanese to spread the word and encourage International Moto Gymkhana competitions. Contact us via www.motogymkhana.org for more information
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Old 11-21-2012, 02:12 PM   #825
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Out their doin it Raybakh!or if it's more appropriate.
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