Simple classroom tool relating "hanging off" to corner speed

[Kevin400F]

I whipped up a little physics model that I'll bring to class on Saturday. My intent is to show how weight transfer (hanging off the bike) relates to the bike's lean angle and therefore corner speed.

Take a look at the series of pics and let me know what you think.

[Kevin400F]

Better pics:

[kenup283]

good idea, I like this kind of stuff. It took me a bit to see the c.g. symbol in the photos, you may want to change the grey to white to contrast better.

I like the idea of showing the angle from the tire patch through the combined bike + rider c.g. vs thinking about lean angle as just that of the bike. With this you can also show how you can get the same relative angle through the combined c.g. while keeping the bike more upright. That discussion can carry over to the points of traction and rolling on the throttle vs lean angle. A good reminder would be not hang off too far until they get moving some, the guy in your model would fall over for sure if it wan't for that nail of a foot peg. :keke:

[bumblebee]

Looks like a good learning tool.
Not like Mudbug who is just a regular tool.:D

[Kevin400F]

Thanks for the feedback. Kenup, I plan to make a nice clear black and white cg symbol and affix it to the washer soldered to the center link.

Bumblebee.....you can never have too many tools at a trackday!

[AaronP220]

Forgive my ingnorance...but I have no clue what you're showing me here.

[Godsuki]

Great prop Kevin! It's going to be very useful!

And Bumble Bee, you're right, Dustin is a tool :D :keke:

[99 Chris]

Forgive my ingnorance...but I have no clue what you're showing me here.

You'll get it afterwards. :nod:

[AaronP220]

You'll get it afterwards. :nod:

I hope so. I'm going to learn after all...

[CarbonJames]

where do you mount this on the bike? i want one.

[spartandude]

where do you mount this on the bike? i want one.

It is for an in class object lesson, but since I know you ride track I hope you are kidding.

Nice physics model though. The "nail" reminds me that I really need to get a sport bike for corner fun. This 750 has ridiculously poor max bike lean and body position can only do so much (well, at least if I am worried about falling off).

edit: "LSTD mini racing #65" nevermind.

[CarbonJames]

It is for an in class object lesson, but since I know you ride track I hope you are kidding.

Nice physics model though. The "nail" reminds me that I really need to get a sport bike for corner fun. This 750 has ridiculously poor max bike lean and body position can only do so much (well, at least if I am worried about falling off).

edit: "LSTD mini racing #65" nevermind.

:rofl:

[SpeedCheeser]

Forgive my ingnorance...but I have no clue what you're showing me here.

Someone correct me if I'm wrong, but I think the bottom block is supposed to represent the bike, the top block represent the rider, and the needle is basically turning ability. So I think what the model is showing, is that if you hang off the bike, you increase the turning ability while keeping the bike at the same lean angle.

[99 Chris]

where do you mount this on the bike? i want one.

:rofl:

It is for an in class object lesson, but since I know you ride track I hope you are kidding.


Nice physics model though. The "nail" reminds me that I really need to get a sport bike for corner fun. This 750 has ridiculously poor max bike lean and body position can only do so much (well, at least if I am worried about falling off).

edit: "LSTD mini racing #65" nevermind.


:rofl::rofl::rofl:


Someone correct me if I'm wrong, but I think the bottom block is supposed to represent the bike, the top block represent the rider, and the needle is basically turning ability. So I think what the model is showing, is that if you hang off the bike, you increase the turning ability while keeping the bike at the same lean angle.

Pretty much!! I'm going to let Kevin explain it, as it's his little project and he's the instructor! :nod:

[switch]

Forgive my ingnorance...but I have no clue what you're showing me here.

don't worry, this thread is over the heads of 98% of the people on this forum.

[CarbonJames]

don't worry, this thread is over the heads of 98% of the people on this forum.

are you "profiling" people of MH?

maybe it is a great tool but, the truth is that it just won't work for everyone.

[Jason73]

very cool!

[switch]

are you "profiling" people of MH?

maybe it is a great tool but, the truth is that it just won't work for everyone.

lol yea, im guilty of 'profiling'. i like the tool, its pretty neat and kudos to kevin for coming up with a classroom instruction tool. i really liked the tire demo i saw at a RS class session. learned about contact patch, lean angle, and other fun things using a tire. obviously you don't fall in that 98% ;)

[DrAwkwArD]

Looks like something that would be in some sort of special edition of Code's Twist the Wrist (trying to get ready for track riding:D). Should help out. I'll be in that noob class...but I knew what the tool was for. Do I get a cookie or something...perhaps a ribbon??

[99 Chris]

Looks like something that would be in some sort of special edition of Code's Twist the Wrist (trying to get ready for track riding:D). Should help out. I'll be in that noob class...but I knew what the tool was for. Do I get a cookie or something...perhaps a ribbon??

You'll get a hug....






.. from The Tim :keke:

[DrAwkwArD]

You'll get a hug....






.. from The Tim :keke:

Awwwww. I'll be sure to be wearing my leathers :rofl:

[civicious]

Going by your classroom model, please take a look at these images and tell me which of these riders are cornering slow and which are cornering fast...


http://img.photobucket.com/albums/v325/CRVTEC/W2.jpg
http://img.photobucket.com/albums/v325/CRVTEC/D1.jpg
http://img.photobucket.com/albums/v325/CRVTEC/W3.jpg
http://img.photobucket.com/albums/v325/CRVTEC/AL1-1.jpg
http://img.photobucket.com/albums/v325/CRVTEC/D2.jpg
http://img.photobucket.com/albums/v325/CRVTEC/W1.jpg

[SBK Pilot]

:happy1:

[Kevin400F]

civicious wrote:
Going by your classroom model, please take a look at these images and tell me which of these riders are cornering slow and which are cornering fast...

Hmmm..... The way I see it, only the rider with daylight under his knee is actually moving. All the rest are static props, posed in position supporting themselves on their knee for a photo op.......

[99 Chris]

civicious wrote:
Going by your classroom model, please take a look at these images and tell me which of these riders are cornering slow and which are cornering fast...

Hmmm..... The way I see it, only the rider with daylight under his knee is actually moving. All the rest are static props, posed in position supporting themselves on their knee for a photo op.......

:rofl: :rofl: :rofl:



Good one, too, Wil.. I only recognized a few of those!! :happy3:

[civicious]

Seriously though...

[Godsuki]

Seriously though...

I believe the point Kevin is trying to make is, that while there are exceptions to most rules, that by getting your body off of the bike, you will be able to corner faster, with less lean angle on the bike. There is a fine line between too much and too little movement, but I'm sure you'll agree, as with any skilled track rider, that you must move your body to get the maximum traction/lean out of your machine.

Sometimes exageratted examples make the best visual props for novice riders to easily grasp. The teaching isn't off, but the prop drives the point home.

[civicious]

Well said, Tim

[Kevin400F]

Thanks for all the feedback. What I'm hoping the little prop will help us illustrate is that for a motorcycle & rider to go around a turn of a given radius at a given speed, the center of mass must be shifted inboard of the tire contact patches by a given amount.

The center of mass of the bike/rider combination is variable. The farther inboard the rider's mass is moved, the less the bike's mass has to be moved (leaned) in order to achieve the same combined result. This is useful if you are on the verge of running out of cornering clearance (dragging hard parts), or if you just want to keep the bike up closer to the center of the tire so you can get on the gas sooner.

As far as guessing who is cornering fast or who is cornering slow by looking at still pictures, you would have to know the radius of the corner the bike is arcing through. You could be at max lean at 20mph on a really tight corner, or at 100mph on a huge sweeper, and it could look virtually the same in a still shot.

[andygill17]

Mick Doohan FTW!

Going by your classroom model, please take a look at these images and tell me which of these riders are cornering slow and which are cornering fast...

http://img.photobucket.com/albums/v325/CRVTEC/D1.jpg

http://img.photobucket.com/albums/v325/CRVTEC/D2.jpg