Gymkhana

Discussion in 'The Perfect Line and Other Riding Myths' started by Vulfy, May 6, 2012.

  1. andmoon

    andmoon Long timer

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    Does this kind of gathering happen here in Joisey?
    How does one get invited to these things?
  2. Vulfy

    Vulfy Been here awhile

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  3. ohgood

    ohgood Long timer

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    man, can't wait for my 17" wheels to get here... the drz is so gonna rock with something other than knobbies on it ! :D:clap
  4. rthuey

    rthuey twist your wrist!!!

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    insanity is not as easy as i make it look
    nice meeting you all on saturday. reviewing the video i took, the first clip from the end of the course i did not care for. everyone is mostly far away. until they get towards the end. the other clips i took after borrowing jezza's helmet strap came out as jpg. turned the machine off and on 5 times but somewhere in the getting the thing mounted onto my helmet i switched the go pro to stills instead of movies. sorry. which means i took 5 stills.

    looking forward to another session in a couple weeks.
  5. Vulfy

    Vulfy Been here awhile

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    I managed an hour long trip today, between the rain. Did get SOAKED coming back though, pants are still drying :rofl

    I'm having so much fun doing this though. I'm trying to get to the level of full lock turn with no hands, which is a bit tougher than at speed and shallower lean angle.

    <iframe width="560" height="315" src="http://www.youtube.com/embed/c8kHI8yUF1I?rel=0" frameborder="0" allowfullscreen></iframe>
  6. Vulfy

    Vulfy Been here awhile

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    A great clip, even if a bit goofy.

    Illustrates a couple of really important principles.

    1. Motorcycle can be controlled with rear wheel, by leaning and letting handlebars point into the inside of the turn (don't fight them).

    2. Lean angle is CRUCIAL to tight turns, at full lock.


    <iframe width="640" height="360" src="http://www.youtube.com/embed/yw73zLZgtbk?rel=0" frameborder="0" allowfullscreen></iframe>
  7. N-m

    N-m Captain 2 Sexy

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    I was doing lazy circles at idle in wet grass this week in both directions. I could easily get close to full lock on either side but going to and staying at full lock was very difficult for me so I will have to continue working on this.

    A balance of pressure on the outside peg and just the right angle as you said makes it easy. You also have to learn to put a lot of faith in your bike since it knows what it is doing.
  8. TheWall

    TheWall 0 miles and counting

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    Awesome clip!

    Seems to me someone (Vulfy, IIRC :) on the forum last summer was trying to point out exactly this same principle and explain how it works. The explanation was convincing, but the proof is in the seeing. Thanks for sharing the video!
  9. pterus

    pterus n00b

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    i think he is exercising there, but here you have the real practical demonstration: http://www.youtube.com/watch?v=bUo8UBHd8a4
  10. Vulfy

    Vulfy Been here awhile

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  11. Storm Shadow

    Storm Shadow Thread Ninja

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    I was looking at. Trading down to aomething under 225cc for the cheap rego when i get my licence back. My cafe racer is 233cc so i pay the same as my vfr800 for rego and i compulsary insurance. Was looking at a ktm 200cc motard. Wonder what its like for motokhana

    [​IMG]
    send on a small touch screen by a guy with fat fingers
  12. Am.E

    Am.E Been here awhile

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    I hope this isn’t too much of a threadjack, but I just want to jump out of lurkdom to comment on this: definitely figure out why your bike does not run well at small throttle openings/low rpm and fix it. At least for a noob like me who is just starting out on this gymkhana stuff, having the right gearing and smooth fueling at low rpm makes a HUGE difference.

    I have 2 bikes: a Ducati Monster and a little Honda CRF230L (small dualsport). I just started practicing the figure 8 this weekend.

    The Monster has a tall first gear (even after I went one tooth smaller on the front sprocket), and it runs TERRIBLY down low. Very jerky, very difficult to have smooth inputs. It was very challenging (read, frustrating) for me to try and “put all the pieces together” with the snatchy throttle, clutch, and brake, while trying to be smooth and learn something new. It was very hard for me to figure out how to use the clutch and brake to apply power smoothly. I left Saturday feeling a bit defeated as to how I could improve.

    On Sunday, I tried again with my CRF. That bike (while also smaller and lighter), has a really low first gear, and runs smoothly all the way down. Result? 15 SECONDS faster after just two tries (yes, the monster times were that embarrassing). After a few more minutes, I had to put my feet further back on the pegs because I was scraping my toes on the ground. I made a lot of progress really fast. Also, I had a whole lot more fun.

    Short version: Same noob, two bikes, 15 seconds difference.

    Its obvious that smaller, lighter bikes are preferable for gymkhana. My point is that, at least for a noob, how the bike is geared and how well that bike runs as very small throttle openings and low rpm makes a HUGE difference in rideability. On the CRF, I can start learning without the variables of the brake or clutch.

    I have no doubt that a more talented rider could put up some good times on my monster. However, I didn’t realize just how much easier the CRF is to ride until I compared the two on the GP8. It will take much, much more practice before I can use the monster as well as the CRF.

    (arbutus, I don’t know why your bike doesn’t run well down low, but seriously, try to find out and fix it. My monster runs poorly because Ducati wants to put up certain horsepower numbers while still meeting emissions requirements, which means the bike runs super lean at part throttle. I am still trying to figure out if I can fix that without paying for a whole new exhaust and ECU that eliminates the O2 sensors ($$$). )

    Sorry for the novel everyone. I hope this helps others who are just starting out.
  13. TheWall

    TheWall 0 miles and counting

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    I like that! :clap If you get one, let us know how it does :)
  14. Vulfy

    Vulfy Been here awhile

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    That looks pretty bad ass.
  15. ohgood

    ohgood Long timer

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    not sure what the point is with the video ? he's just balancing the bike from a different point. if he lets go at any point (at that speed) other than with the bars at full lock, it will fall. the bars at full lock are acting as set inputs.

    lean angle is just part of the recipe. it goes along with (and changes) as the speed does. they're all working together, and influence each other.

    or maybe i missed something again ? :)
  16. TheWall

    TheWall 0 miles and counting

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    Watch the video again, and notice the difference in turn radius with the bike perpendicular to the ground and with the bike leaning into the turn. You *CANNOT* get a max performance turn without leaning the bike into the turn (which explains why you will often see the really good riders counter-balancing, but don't see the really good riders dragging their knees in the tight corners very often).
  17. ohgood

    ohgood Long timer

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    ahhh, ok, he's demonstrating lean angle for faster turns. got it.

    still, why not just ride the bike at different speeds ? it will show the angle wether you're pushing it with a pumpkin or actually riding the bike. and it's easier :)
  18. Vulfy

    Vulfy Been here awhile

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    He is not showing anything ground breaking.

    ohgood, what you are saying is exactly what he is showing. Basically the difference the lean angle makes on the turning radius at the same angle of the bars. And yes, you are absolutely correct that EVERYTHING (speed, throttle, lean, bar angle) together is what makes the complete pictures and gets the bike around the cone fastest, without falling over.

    Here he is just showing steering principle by itself, and of course the bike would fall over without the throttle and speed.

    Also when he is doing the snake, its good to realize that bike can steer itself, based on the lean. So you don't have to fight with the bars to steer the bike.
    Which used to happen to me all the time.

    Again, this is just another look at all the foundations of motorcycle riding. Just a good illustration in pictures, rather trying to explain it in words to someone who might just be starting out with this.
  19. TheWall

    TheWall 0 miles and counting

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    What I got from the video is that speed is irrelevant (with a caveat, which I'll get to in a minute) -- rather, the lean angle of the bike is what determines your turn radius, once the handlebars are at full lock. By pushing the bike at walking speed, he was able to demonstrate that it is not the speed of the bike that determines turn radius; it is the lean angle.

    The caveat is that there are different ways of getting the bike to that lean angle. You can have a higher speed while sitting directly in line with the center-line of the bike, or you can counter-balance to the outside of the turn while leaning the bike aggressively at a lower speed, and either way will work. You have to decide which method of keeping the bike balanced (increasing speed or counter-balancing) is appropriate in your situation.
  20. Vulfy

    Vulfy Been here awhile

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    I like this explanation!