Agreed.He's off the seat at least half assed.

Yes, yes, I see it now, it's becoming very clear, he also is wearing polka dot boxer shorts and his left testicle appears to have been shot off during the great war....LMAO!!!!

Just noticed something...his right hand...on that brake lever.Interesting.This reminds me of something else cool about the new bike.That lever....on my 07 I could never comfortably get one or two fingers riding that lever like that.Even with it adjusted all the way back,and having aftermarkets on there a couple of times as well.

My new baby...one finger...fits perfectly on that lever...small thing I know...but...very cool to me anyway.

"A good American only needs one finger."-Al Bundy

he also is wearing polka dot boxer shorts and his left testicle appears to have been shot off during the great war....LMAO!!!!

Riding that track...or any for that matter...on a regular basis can only better your skills.Your 'muscle memory'..in this case,your brain,can be 'trained' very nicely to respond to the givens that are there during the ride....speed adjustments,leaning,apexing,braking.

UNFORTUNATELY...the street doesn't really allow that kind of mental training but only to a point.If you ride the same roads over and over...you can develop better 'skills'...BUT...the quickness at which things can and do change at any given time on the street make it more difficult for sure.Especially with speed limits and such.I've been really practicing looking ahead more...it's very interesting how the bike will react when I'm adjusting my look 'out there'.I think there's a sweet spot...and every rider has his own spot...where he feels at one with the terrain and the bike and the road ahead.It's going to be a good year I think for relearning with this new machine.It's very intuitive for a bike....very.It responds very well to 'thinking ahead'.Or maybe it's just me.IDK.I do know the speeds at which this bike gets you from 'a' to 'b' has definitely upped the concentration factor...for me anyway.

^^+1 when you ride close to other riders, prolly not the smartest thing in the world to ride right on their line. The apexing rule doesn't usually work exactly as it would if you were all alone.

That picture scares me every time I see it and if I remember correctly he didn't even crash.

How about this one? Yeee hawwww!

* Last updated by: bgordon on 4/6/2012 @ 5:07 PM *

The Doctor is in...

Insane!

DohMG!!

That is insane---I mean that is like a millisecond before the crash--I would swear if I didn't know better.

Now you see Kruz, liter bikes just don't ever touch. no scraping unless you crash. Not so on the 14.

"-I mean that is like a millisecond before the crash-"....in his case...there wouldn't BE any crash...only a nice melding of plastic,metal,leather,and....asphalt.Maybe a tad of fuel just to lube things along....dude IS insane.But you look at that...he's really NOT hanging off.If he were...he wouldn't be gettin that bigazz lean goin on.VERY cool pic....very.That one of Hub's there..that's quite badazz as well...dude takin him on the INSIDE....where there ISN'T any 'inside'....he's makin one....takes steel nerves to pull that off.You can imagine the guy on the 'outside'...what's goin through his mind right about then.I'd say...when yer scared to crash...you get lapped.Not that he's scared(probably pissed )...but kinda makes ya wonder a bit.Startled...ya...very.One second..yer in the clear.Next second...FUC^^^^WTF????Thanks for ruinin my line ya prick.Followed by "don't worry asshole,I'll get ya on the next set".....WHEEEEEEEEE!!!!!!!!!!!!!!!!Guys are awesome...for sure.

* Last updated by: Grn14 on 4/13/2012 @ 12:48 PM *

i posted my equation for hang off over on California Superbikes Cornering forum awhile back and nobodies arguing with it over there. It seems to fit in with their experience.

One guy brought up a very good point though, hanging off may give you less lean angle in a given turn at a given speed and more ground clearance but it gains you exactly nada when it comes down to actual maximum speed you can take that given corner at.

If ground clearance is not an issue, maximum speed is determined only by the friction coefficient of the tires, hanging off or not makes no difference, both riders will take the corner at the same maximum speed.

This is why you see riders hanging off and some not hanging off in the same corner going the same speed in racing photos. Different styles but similiar results.

So to summarize the benefits of hanging off, lowers the CG for more stable handling and decreases lean angle for better ground clearance. It does not make you go faster through a given corner unless you are limited in lean by ground clearance, think Rooks ZX-14 here...LOL!

Don't try this at home, those MotoGp tires have ten times the stick in a corner that our BT-016s and Dunflops have but they last less than 100 miles and then go to the scrap pile. Think flypaper here!

Those guys are awesome riders but on one of our bikes with street tires, they wouldn't look quite so superhuman or they'd end up on their heads.

* Last updated by: Kruz on 4/13/2012 @ 1:45 PM *

Yup...I'd agree totally.Good thread Kruz.Some good stuff in here.(I knew if I waited long enough,I could get off the hook about believing I needed to hang off ).Not for me really...aw,a smidgen maybe..but...I feel more in control staying 'partially' at one with my bike!I get some side shots going sometimes...depending.It's fun to experiment with different things.But my securest feeling while cornering with speed is staying almost right in the centerline of my bike,with my torso off somewhat...but not extreme.Where I can feel the G's push me into the saddle and make the bike grip harder.Feels good doing that.

* Last updated by: Grn14 on 4/13/2012 @ 1:54 PM *

Find what works for you and stick with it. Keith Code says to find your own style in his book on cornering. It's all about being comfortable with the machine. If you're not comfortable, your not going to ride to your potential. I like the hang off the more I use it but it feels a bit strange at first. I think the key is to set your position well ahead of the corner turn I'n point to give your suspension time to settle down. Big weight shifts can get you bobbing and weaving, not exactly confidence inspiring. With time the weight shift becomes almost automatic.

It's crazy but after reading Code's book where he makes the argument not to use rear brake, I've been able to train myself to stay out of the rear brake in a short time. It does wonders for braking into the corners, if you are braking at 100%, the back tire is unloaded anyway and stabbing the pedal can cause instability. A lot of riders use a thumb brake for the rear and drag it when accelerating off corners to keep the front end down. You can learn these new techniques fast with practice.

One guy brought up a very good point though, hanging off may give you less lean angle in a given turn at a given speed and more ground clearance but it gains you exactly nada when it comes down to actual maximum speed you can take that given corner at.

If less lean angle gives you an EVEN SLIGHTLY LARGER contact patch, though, you should be able to go through the same corner faster/safer with less lean angle, no? -bg

We had a big argument on this very point over on the CSB cornering forum and came to the conclusion that tire patch size actually has nothing to do with ultimate traction but everything to do with tire wear.
Sounds counterintuitive but pick up any engineering or physics book and there are only two variables in the Friction Force equation, Normal Force (weight) and coefficient of friction. Surface Area doesn't come into the equation.

I remember doing the classic experiment with loaded wooden blocks back I'n college physics class where different sized blocks, large and small surface areas, were identically loaded and the friction force measured.

Only the weight made a difference; sound crazy but it's old news to a physicist.

The flip side is that for a given Normal Force there would be less wear rate with a wider contact area, if slip under loading occurs as in a tire.

There is more rubber on the road when you're leaned over than when you're upright. Since we're getting into a physics discussion, the forces acting on your tire during cornering are different than those acting on it while upright. Along with weight, centrifugal force must be added to braking and acceleration. Centrifugal force is the force the tires have to act against to prevent you from sliding off a curve on a tangent from the point of lost traction. Lost traction while upright, whether it be from wheel spin or brake lockup can be dealt with a lot easier than lost traction while turning. Weight starts to become a negligible factor as speed increases. Motorcycles are not heavy vehicles (loaded Gold Wings and Boss Hogs excepted) and as speed increases, there is even less weight on the contact patch. Centrifugal force acts at 90 degrees to weight, so there is some counteraction going on there. This is why proper motorcycle tires are designed with more contact area on the sides than in the center. it's also why ABS and traction control are becoming the latest trend in motorcycles.

* Last updated by: Danno on 4/15/2012 @ 9:48 AM *

bg is suggesting that shifting body weight might allow for faster cornering. the bike will be more upright and have a smaller contact patch not bigger. However, being more upright, the bike is less likely to skid out and there is more lean angle clearance if that is an issue in the particular situation. If the bike is more stable and less likely to scrape thats all I need to go faster.

Kruz is saying that contact patch alone doesn't make any difference to tire grip which is hard to believe. There must be some error there . Why do we use slicks on the race track? Why do drag cars use extra extra wide tires?

* Last updated by: Rook on 4/15/2012 @ 10:23 AM *

"If less lean angle gives you an EVEN SLIGHTLY LARGER contact patch, though, you should be able to go through the same corner faster/safer with less lean angle, no? -bg"....that's why they're running 35,36 psi.Lower than the street anyway.Kruz made a very good point....tires...compounds.That's a BIG factor right there...probably THE most important one.Grip.Flex.Bike weight.Very important.How wide is the contact patch at any given lean angle?Not very much.Coulple of inches.With race tires,it's not gonna change too much when they're heated up and doing what they're designed to do.Kruz said something about 100 miles or so.That sounds right for a professional racer/team watching the tire quality deteriorate as the race continues or whatever.Those race tires are NOT the same acting deal as a street tire.Gotta remember that when you're expecting your street tires to perform like a race tire.

* Last updated by: Grn14 on 4/15/2012 @ 1:13 PM *

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   Question

Why doesn't friction depend on surface area?

Asked by: Elizabeth Stewart

Answer

Although a larger area of contact between two surfaces would create a larger source of frictional forces, it also reduces the pressure between the two surfaces for a given force holding them together. Since pressure equals force divided by the area of contact, it works out that the increase in friction generating area is exactly offset by the reduction in pressure; the resulting frictional forces, then, are dependent only on the frictional coefficient of the materials and the FORCE holding them together.

If you were to increase the force as you increased the area to keep PRESSURE the same, then increasing the area WOULD increase the frictional force between the two surfaces.

Answered by: Paul Walorski, BS Physics

SUMMARY OF FRICTION

The maximum force of static friction that exists between two surfaces is proportional to the normal force and mostly independent of area of contact. This situation is shown here: N = the total normal force (force perpendicular to the horizontal surface) which is essentially the weight of the object. The coefficient in that equation is called the coeffecient of static friction and that depends on the material:

When the object is actually moving, the friction is said to be kinetic friction which is generally less than static friction.

If we add more mass we increase the normal force (N) (because the weight has increased) and hence we have increased the total frictional force. This is shown here where it can be seen that twice as much force must be applied to move two bricks instead of one (the force meter reads twice as large).

In general frictional forces are independent of the area of contact although this is an empirical observation not a theory. Consider a metallic brick and a metallic table. The reason that friction is nearly independent of surface area is if the "microscopic" area of contact of the brick to the table is independent of the orientation of the brick. If this is not the case, then friction will have a small dependence on area. In normal circumstances, with the largest surface area of the brick in contact with the table there are a large number of "contact" points that support the load. With the smallest area in contact (brick standing on end) there are fewer contacts but as long as the area of each contact is larger due to the higher pressure (same force, smaller unit area) then there will be no difference in the amount of static friction. Over wide limits, most materials follow this and hence friction is largely independent of surface area. iF you have a situation where the microscopic contact area does not scale in accordance with the pressure, then static friction will depend upon orientation.
The following example (which we will do in class) demonstrates the general rule that friction is not dependent on total area of contact

Try the JAVA Friction Experiment: (not complete yet)
Although their are 5 symbols only three of them are active: You will either get:

a square block of mass = 100 grams
square block of mass = 200 grams
a rectangular block of mass = 200 grams
You may adjust the angle of the incline. The four vectors that represent the gravitional force (red), the normal force (blue), the frictional force (green) which opposes the motoin, and the component of the gravitational force (white) which is trying to pull the block down. You can adjust the angle such that the green vector is bigger than the white vector and therefore nothing will happen. After you have set the angle, hit the start button and watch the block slide down the incline and watch how the vector forces change slightly. The simulation runs for 10 seconds; this may not be long enough to cause the block to completely slide

* Last updated by: Kruz on 4/15/2012 @ 2:06 PM *

Turns out that a skinny drag racing tire would work just as well on a top fuel dragster... for about ten feet, then the tire would overheat due to the lack of mass available to transfer heat away from the surface. Rubber tires are petroleum based so heat changes their chemistry, they become 'greasy', friction coefficient drops to near zero and the tire begins to spin wildly completing it's destruction. Big wide tires act like a giant heatsink.

And what do those drag tires do in the first 10 ft or so?They stand up...become narrower....and why do you think they do that?...because the designers understand the very things you just posted about.It's no guessing game.These guys are professionals.Same with the race guys...professionals...being guided by PHD's and such.NOT yer backyard handyman.

Race tires are designed to behave a certain way...for the track.That's why putting race tires on your 500 something lb street motorcycle is foolhardy at best.They know what they're doing.You don't see race guys rolling on street tires either.Not for a real race deal.Testing...yes...but racing...nope.

* Last updated by: Grn14 on 4/15/2012 @ 2:13 PM *