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[naitram]

      Trying to get my head around this one.  I was taught that turning is a matter of physics: speed, wheel base and lean angle and that you change body position to stabilize and direct yourself and the bike.  In other words, how sharp you (cornering radius) will turn depends on speed, wheel base and bike lean angle.  You change body position to achieve correct lean angle.  How is it that a weight transfer alone can change the cornering radius for a given lean angle?      Can someone explain how this works?  Thanks!   Mark, do you want to chime in on this?   Inquiring mind(s) want to know. 

GK

its a center of gravity thing

[Midnight Rider]

      Trying to get my head around this one.  I was taught that turning is a matter of physics: speed, wheel base and lean angle and that you change body position to stabilize and direct yourself and the bike.  In other words, how sharp you (cornering radius) will turn depends on speed, wheel base and bike lean angle.  You change body position to achieve correct lean angle.  How is it that a weight transfer alone can change the cornering radius for a given lean angle?      Can someone explain how this works?  Thanks!   Mark, do you want to chime in on this?   Inquiring mind(s) want to know. 

GK

Assuming that you countersteer to actually turn, rather than shifting your weight to make the bike lean over.(of course, whether you know it or not, you're countersteering...the bike won't turn otherwise, at least not over speeds of about 15mph), when you "hang off" the bike, the center of gravity changes, requiring less bike angle to achieve the same turning radius for any given speed.  Even something as simple as looking over the inside mirror by shifting your upper body will significantly reduce the lean angle of the bike needed to take the curve...shifting your butt off to the side makes an even more dramatic effect, otherwise the bike racers would never make the turns they make at the speeds they go.  Changing the CG allows you to carry more speed through the turn with less scraping of parts.

The number of riders who don't know about countersteering is amazing and would surprise you.  I'm not saying anyone here doesn't know, but just a general statement.

[spydglide]

You learned how to do that riding those 'choppers' that were slammed down so low that in order to get around a corner, you had to hang it out there or you'd never make those tight corners, huh Terry?  har.  spyder

[Midnight Rider]

Here's a pretty good explanation I found:

Leaning counteracts the centrifugal force trying to flop the motorcycle over on the side away from center of radius of the curve. Centrifugal force acts on the Center of Gravity trying to push it outward. Gravity acts on the CG trying to pull it down to the ground. Balance occurs when the centrifugal and gravitational forces are equal.

Hanging off changes the position of the CG. It moves more mass to the inside of the bike. Imagine that the bike is upright and balanced. Now hang some mass on the left side handlebar. The bike will fall to the left because the CG is not on the vertical centerline any more. Same thing.

Hanging off changes the position of the CG such that the bike is more upright going through the turn. This does two things. First, it keeps low hanging stuff (like pegs) further from the ground giving more usable lean angle. Second, it keeps the tires more upright reducing the amount of squirm in the contact patch, increasing traction a bit.

The angle of the front tire in relation to the axial centerline of the bike is what controls the radius of the curve. Lean angle balances the centrifugal force with the gravitational force. (Remember that force = mass X acceleration. Gravity is an acceleration, changing directions is an acceleration).

[Midnight Rider]

You learned how to do that riding those 'choppers' that were slammed down so low that in order to get around a corner, you had to hang it out there or you'd never make those tight corners, huh Terry?  har.  spyder

Yea, that's the ticket 

In those days, Spydy, I didn't know half the time whether I was hanging off the bike or sitting up straight.  It's a wonder I'm still on this earth...

[GregKhougaz]

What Neal and Terry says is correct, I believe.  I love to experiment with counter steering and find that pushing the inside hand forward helps with proper body position.  Neither Terry nor Neal specifically explain the original statement, "get thru a corner faster w/o leaning the bike as much....."  What Terry says about center of gravity is true but simply helps the bike lean which in turn, (pardon the pun) turns the bike.   So while body position / shifting will help you lean, I don't see how it can possibly get the bike through a corner "faster without leaning as much."  That defies the laws of physics that Terry explained so well above. 

Anyone? 

Thanks again. 

[spydglide]

Greg, I thought he explained it extremely well....esp. the paragraph that described keeping the bike more 'upright' so as to not scrape low-hanging parts and with the center of gravity change you're able to accomplish this with the weight shift instead of as much 'lean' to get around the corner at the same speed.  Awww, he did it much better than I can.  Re-read his explanation again and see if it doesn't become clear.  spyder

[GregKhougaz]

Working on it.....

[FLYNDYNA]

glad to hear you are all right...get riding again soon!

[Talon]

Glad your ok! I wouldn't put extensions on my bike, the RKC sits 1" lower than the standard RK and I already scrape the floor board mounts! I' counter steer but will have to practice the chin on the mirror thing Chip.

Craig

[CVOJOE]

Jon,
Sorry to hear about your new, beautiful ride getting dinged up. Glad you came out of it with only minor scrapes and bruises.

My SERK is lowered and has the extended boards and they do get the ole legs out away from the engine heat and provide more breeze on the balls as well. But with the lowered stance man do they scrape when you are agressive on the road. The scraping does let you know the limits quickly, but I've always worried about the extensions catching something and taking the control literally out of our hands. Maybe time to swap back to the ole MOFOCO standards? 

Get her fixed and back in the breeze!!
Joe

[JCZ]

They had us practicing by putting our chins on top of the mirror on the bagger as we went around a curve. SBB

        

[Jock]

What I can say is this guy is the Iron Man!  As someone who followed him at the the time of the accident I fully expected not to see him stand up after it...

Dude I was in awe...

You have certainly left your mark on that road!  Sorry for your fortune butit certainly could have been worst! 

God speed on the repairs and back in the wind soon!

[spydglide]

Hope the State doesn't send you a bill for marking up their hwy.  I hear they need the $$.    har. spyder

[Cigarmike]

Good your ok Jon, some new custom paint will make ya feel a little better.