Ducati Monster Forum

Moto Board => Riding Techniques => Topic started by: S21FOLGORE on December 23, 2012, 05:36:14 PM



Title: Illustrated "how-to" : U-turn
Post by: S21FOLGORE on December 23, 2012, 05:36:14 PM
Ah, " u-turn", ... yes, u-turn on a Ducati monster ...
Apparently, quite a bit of people find this task as , somewhat , "challenging".
It's OK, you don't have to admit that you suck at low speed turn in front of your riding buddy .
You can read this "how to", understand the reason why your u-turn fail first, then you can practice while staying anonymous. Isn't internet wonderful?

Well, practice is important, but you need to know the basic principal of the "u-turn" , especially on Ducati. (Because it's not the "easiest to do u-turn on" motorcycle in the universe.  ) 

1. Typical scenario of u-turn fail

Example A) Running wide
Typically, total newbie's u-turn fail goes something like this.
(http://i342.photobucket.com/albums/o420/ZX750E2/U-turn_1_zps97bf5347.jpg)

How does this happen ? Let's take a look at the picture.
(1) the rider keeps the bike standing upright , well, more like "can't lean over the bike" because of fear ( of falling down).
(2), And the steering is not turned all the way to full lock. Shoulders, elbows, pretty much all of his upper body tens up, keep pushing inside bar .(causing the bike turning wide)
(3) already used up a little more than a half of available space (road width), the rider starts thinking " I'm not going to make it ", then look at the curb, thinking " I don't want to go there, I don't want to go ... " (target fixation), then, by instinct, grabbing the front brake and falls.



Example B) Engine stall (or, pulling the clutch lever in)

(http://i342.photobucket.com/albums/o420/ZX750E2/U-turn_2_zps213e468b.jpg)

How does this one happen, then? This rider starts better than the previous example. Look at the lean angle of the bike and the helmet.
(1)At the begging of the turn,  he's already looking at the end of the turn. Both shoulders are down, arms are relaxed. So far, so good.
(2)Unfortunately, while turning,
a. Engine stalls
b. Sensing the sign of engine stall, so the rider pulls the clutch lever in (thus, cutting off the traction)



OK, now you know what cause u-turn fail. You can work on these things one by one, then, at the end, you'll be able to to the u-turn, right?
But, there's one more thing you should take a look before hitting an empty parking lot.

2.  The basic understanding about u-turn


Camber thrust
(http://i342.photobucket.com/albums/o420/ZX750E2/U-turn_3_zps6bd2b4dc.jpg)

Ever heard of "camber thrust" ?
A coin rolling on the table , as the coin's speed slows down a little bit, it starts leaning to one side. And the coin starts to turn into that direction because there's a force generated to turn (changing the direction of the coin). This is camber thrust. Imagine taking off the rear or front wheel of your bike and roll it on the ground. The same thing is happening to your motorcycle's tires .This is why turning radius becomes smaller when the bike is leaned more, even though the amount of the front end steer is the same.

(http://i342.photobucket.com/albums/o420/ZX750E2/U-turn_5_zps321050ed.jpg)

As the coin's speed becomes slower, it leans more, and the turning radius becomes smaller.
In the end, the coin's speed becomes zero and it lays down on its side.

Unlike coins, motorcycles come with the throttle, which can be used not only to move the motorcycle forward, but also to stabilize it, to prevent it from falling down.
If the coin had the throttle, it could keep turning around and around, maintaining the same turing radius, so long as it is getting enough" traction"

(http://i342.photobucket.com/albums/o420/ZX750E2/U-turn_4_zps53c912bb.jpg)

Yup, you already guessed it. Pulling the clutch lever in means you are cutting off the traction. Something you wouldn't want to do during the turn.

3. Practice


A) Clutch control
Unfortunately,Ducati's big twin engines don't run smoothly at really low rpm. At the speed you'd do u-turn (pretty much the walking speed), the engine would bog, stutter, very difficult to control without touching the clutch at all. Some people pull the clutch lever in constantly, because of fear of engine stall.
And that's  the bad example of clutch control.
Take a look at the picture.
(http://i342.photobucket.com/albums/o420/ZX750E2/U-turn_6_zps410f8400.jpg)

This is an example of using clutch as on / off switch. BAD example.
Then, what is the right way ?

Clutch modulation

You have  heard some people talking about "clutch modulation", right?  That's what you need to learn ...

(end of long introduction, to be continued to next part ...)






Title: Re: Illustrated "how-to" : U-turn
Post by: memper on December 23, 2012, 06:38:00 PM
Love the illustrations!


Title: Re: Illustrated "how-to" : U-turn
Post by: Slide Panda on December 27, 2012, 06:22:25 AM
Awesome! More Illos!

Your other set(s) were great - are you planning do a book? Even a self publish PDF one?



Title: Re: Illustrated "how-to" : U-turn
Post by: S21FOLGORE on January 03, 2013, 09:12:51 AM
Thanks for the comment.

OK, let's take a look at the picture below.
If you try to visualize the clutch action, it would be something like this.

(http://i342.photobucket.com/albums/o420/ZX750E2/Clutch_1_zps083af53a.jpg)

Look at the lever stroke.
(1) - (2)  is free play. Nothing happens here.
(2) - (3)  is the actual (effective) clutch lever stroke. As you can see in the picture, wet clutch system has much longer stroke.( And the clutch engaging action is a lot more forgiving.)
(3) - (4) is another "free play" zone. You can easily tell, when the lever is in this position, the bike won't move no matter how much you rev up the engine. The power does not get to the real wheel.

The first and the most important thing here is to teach and train yourself NOT to pull the clutch lever all the way in ( past  (3) position ) when the bike is in motion, even when up / down shifting.
The clutch lever only needs to travel around 3 - 5 mm on dry clutch model, about 10 - 15 mm on wet clutch model.

Try riding as slow as possible in 1st gear. Don't use front brake. When it feels like it's going to stall, dip the clutch momentarily. You only need just a little dipping, not completely disengaging. That just a little bit of clutch slipping is all you need.

(http://i342.photobucket.com/albums/o420/ZX750E2/Clutch_2_zpsa0c19257.jpg)

Another important thing is to understand " free play ".
Anything that moves, rotates around has free play. All motorcycle control system, clutch, brake, throttle, shifter has free play.
Clutch engage / disengage action does not start when you start pulling the lever.

<to be continued ...>



Title: Re: Illustrated "how-to" : U-turn
Post by: Slide Panda on January 03, 2013, 09:18:58 AM
Another point you might add is use of the rear brake during slow maneuvers.

And keep up the good work. The hand done illos are very cool


Title: Re: Illustrated "how-to" : U-turn
Post by: freeclimbmtb on January 03, 2013, 10:40:18 AM
You can draw in quality I can barely dream.  And I hate you for it.  Keep em coming.  Subscribed.   [thumbsup] 


Can we get one of how to clutch a wheelie too?  (professional rider, closed course...of course.)


Title: Re: Illustrated "how-to" : U-turn
Post by: Howie on January 03, 2013, 12:41:11 PM
I see a book in S21FOLGORE's future [thumbsup]


Title: Re: Illustrated "how-to" : U-turn
Post by: thought on January 03, 2013, 09:46:14 PM
I love it everytime you post up one of your illustrated how to's.

Keep up the good work and like Slide Panda mentioned, using the rear brake helps a lot too.


Title: Re: Illustrated "how-to" : U-turn
Post by: bob795 on January 04, 2013, 08:16:53 PM
Love it  [thumbsup]

BTW, regarding u-turn. I always find it easier for me to make u-turn, and tighter u-turn without putting my foot down, when there's a divider in the middle of the street. Say, a street is divided into two lanes by a divider (green zone we call it, about 1 meter wide) I find it easier to do u-turn then on a similar width street that is not divided. I don't know why. ???


Title: Re: Illustrated "how-to" : U-turn
Post by: Slide Panda on January 07, 2013, 06:31:45 AM
I don't know why. ???

Perhaps it gives you a mid turn reference point?


Title: Re: Illustrated "how-to" : U-turn
Post by: freeclimbmtb on January 07, 2013, 07:19:38 AM
I just do a burnout and revolve around my front wheel.  Ok I'm kidding, my feet don't touch the ground well enough to pull off something like that.  I was a little squilly at first, but I dont even think about it anymore.  I feel like when I was nervous about it, I would have my feet out like training wheels just in case I got shaky. 

But hey, whatever works to keep the shiny side up right?


Title: Re: Illustrated "how-to" : U-turn
Post by: tex-mex on January 08, 2013, 07:20:23 AM
Post a You Tube video on you drawing the illustrations.  I have to see your technique.  Post your portfolio on the gallery.  Why can't I draw like that!  I suck!


Title: Re: Illustrated "how-to" : U-turn
Post by: LowThudd on March 28, 2013, 11:22:42 PM
Very helpful guide! Thanks!


Title: Re: Illustrated "how-to" : U-turn
Post by: Teeaarge on April 13, 2013, 06:42:05 AM
Excellent Illustrations,  Please post more about other techniques. Thanks.


Title: Re: Illustrated "how-to" : U-turn
Post by: spolic on October 23, 2013, 03:47:44 PM
WOW! These are so cool!  [thumbsup]


Title: Re: Illustrated "how-to" : U-turn
Post by: S21FOLGORE on December 16, 2013, 01:50:11 AM
 Due to the lack of free time, I really couldn't make any progress, but I am still trying to do this thread.
(It's been almost a year since I posted the last time ...)

Hopefully I'll post before the end of the year.
Meanwhile, here's the short video clip of the u-turn.
U turn on Ducati Monster copy (http://www.youtube.com/watch?v=gCoH7rjEl_U&feature=youtu.be#)


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