Thread: Gymkhana
View Single Post
Old 08-29-2012, 04:38 PM   #299
Vulfy OP
Studly Adventurer
 
Vulfy's Avatar
 
Joined: Feb 2012
Location: NYC
Oddometer: 547
Quote:
Originally Posted by TheWall View Post
...which brings up a technique question that's been bugging me since my last practice session last Saturday morning. I set up a course that was basically a series of zig-zags about 25 feet apart (and maybe ten to twelve feet wide -- a parking space and a half, anyway -- per row). Riding the course felt great.

Then I watched the video when I got home...I was turning like the Exxon Valdez! (I haven't edited or posted the video yet, so no link to show what I'm talking about).

The course that I modeled this from called for seven feet between cones, giving a max turning diameter of fourteen feet; I was easily going that far beyond the cone that marked the center of my turn (meaning a twenty-eight foot turning radius ). I know I'm capable of making much tighter turns than that; I routinely make U-Turns on the street from the middle of my lane into the middle of the oncoming lane, and I can easily do 360s on a low-traffic, two-lane residential street near my house.

I was doing all the other things Vulfy and Harvey Krumpet have mentioned in other posts (turning my head to look where I want to go, trail braking through the turn, etc.), but I'm thinking that I was waiting until after I passed the cone to initiate the turn when I should have been already started the turn by the time I passed the cone. What do you think? If you are trying to make a 180 around a cone, do you start the turn before you reach the cone, or as you reach the cone?

Thanks!
Motogymkhanaman posted a simple operation to finding the smallest turn radius of your bike. It doesn't necessaraly help you with the technique of HOW to attain that radius, but at least knowing how tight your bike can potentially turn, can help you judge your progress.

Get off the bike to either side. Hold bars and turn them to full lock to your side. Have some guide marks on the pavement so you can judge how wide you are turning. Walk the bike straight up, with bars turned, until you make half a circle. That's your larger turn radius.

Now do the same thing, only at the same time as you lock the bars, tilt the bike to its side as much as you can, and walk it like that. This is of course might not be fully achievable depending on the weight of the bike, and your own strength.

This gives you the tightest radius your bike can attain.

The difference might actually be in just few feet, or at least it was in my case, but it was still a good learning exercise.

With the information on the potential turning radius of your bike, next step is the time it takes you to turn it.
Faster you go into the turn, the harder it is to actually keep the bars at full lock, but easier it is to keep the bike leaned into the turn.
Slower you go, its easier to keep bars at full lock, but bike wants to fall over.

The problem with me, is that feel of loss of control when the bars are at full lock. We instinctively push and pull on the bars in a turn, even if its just millimeters to control the lean of the bike.

When there is no room in one direction, ei full lock, we lose that ability to fine tune our balance on the bike.

At this point, you have to steer with throttle. If you are falling over, release a bit of the rear brake or add more gas. If you are loosing full lock and your bars drift away to the center, slow down by adding more rear brake.

What helps me, is to start really nice and easy and slow. Have the bike fully upright, get the bars to full lock, and ride nice and slow in this position, straight up. Then slowly start adding lean to the bike, which will automatically add a bit more speed. On and so on.

As far as the entry into the turn, that is a tricky subject in itself.

Again its a balancing act. As motogymkhanaman referenced to his Japanese teachers, you need to be "leaping" from cone to cone. Slow around, fast to the next, slow around.

What that means is that you need to be twisting that throttle wide open at the exit, but be fully on the brakes at the entrance.... and then trail brake into the turn.

You WILL drop your bike practicing this, so just take it easy and practice what you can, if you are unable to invest in more "dedicated" gymkhana machine and its protection, AS WELL AS YOURS. Please wear armor. It really hurts falling down off the bike, even at slow speeds.

So at the entrance to the next turn, you are going all bat shit out. However you need to drop ALL of that speed so you can successfully turn bars to full (or at least near full lock) and negotiate turn in the tightest diameter possible.
You brake hard, and you brake INTO the turn.

This action makes your front wheel fold under you. You can get two results out of this.
One: you go down.

Two: front wheel folds under you right into the full lock position, and its up to you to control the throttle, the brakes and your balance, to keep the bike moving and falling over, right into a nice tight turn.

If all of this sounds complicated.... it is.... I SUCK at it.

P.S. as far as the actual entrance point into the turn... that sort of depends on your speed. You don't want to do swooping turns around cones. So its all in your braking and speed. I would say, generally, start turning when you are by the side of the cone. That would require a fast flick into the turn though.
Also, the turns are offset from the cone. Treat cones as NOT the center of your turn, but as an exit apex.

So next time when you practice, note how far away from the cone you are, when you complete the turn at an exit. Next time at the same turn, offset your entrance point to the side, by the same distance that you had your cone to your side at an exit.
This way, when you complete the turn, you should be almost brushing the cone with your bike.

As another gymkhana teacher told me, is to try to turn around the cone in such a way, that the tip of the inside handle bar, is positioned OVER the cone at the apex of the turn.

Vulfy screwed with this post 08-29-2012 at 05:01 PM
Vulfy is offline   Reply With Quote