Two Wheel Physics
Seasoned HDF Member
Joined: Apr 2014
Posts: 5,815
Likes: 2,555
From: UK
Which is why you should always do your braking before entering the turn - and not take them literally as fast as the bike can handle it or you have zero margin for error if you need to adjust in the turn itself.
Club Member
Joined: Jul 2014
Posts: 11,468
Likes: 3,572
From: Idaho
In addition to "Twist of the Wrist II", I will strongly recommend the following two books from my library:
"Total Control - High Performance Street Riding Techniques", by Lee Parks
"Riding in the Zone - Advance Techniques for Skillful Motorcycling" by Ken Condon.
And, for those of us who never lean very far (
) "Maximum Control - Mastering Your Heavyweight Bike" by Pat Hahn.
All available on Amazon, of course.
Yeah, well, I was trying to be gentle!
In addition to "Twist of the Wrist II", I will strongly recommend the following two books from my library:
"Total Control - High Performance Street Riding Techniques", by Lee Parks
"Riding in the Zone - Advance Techniques for Skillful Motorcycling" by Ken Condon.
And, for those of us who never lean very far ( )
"Maximum Control - Mastering Your Heavyweight Bike" by Pat Hahn.
All available on Amazon, of course.
In addition to "Twist of the Wrist II", I will strongly recommend the following two books from my library:
"Total Control - High Performance Street Riding Techniques", by Lee Parks
"Riding in the Zone - Advance Techniques for Skillful Motorcycling" by Ken Condon.
And, for those of us who never lean very far (
) "Maximum Control - Mastering Your Heavyweight Bike" by Pat Hahn.
All available on Amazon, of course.
Big Kahuna HDF Member
Joined: Nov 2008
Posts: 35,506
Likes: 27
From: Calgary eh
While I am sure all these are very good sources for technique, my attempt as the OP is to explain or provide a good reference to explain the physics behind the forces that we experience while riding. I in no way attempted to give information that would result in anyone being a better rider, just more informed about what is going on around them. I think you should post this under a new thread called "Resources for Better Riding Technique", it would be more useful than burying it in the 3rd page of this thread.
I think you need to go back to physics 101 if you think that is a good reference.
He doesn't know how to balance forces, and like someone quoted him saying different parts of the tire are rotating at different RPM!! Haha. Too funny.
Seriously though, it's a lot of empirical info and the guy tried to embellish with quasi scientific terms.
Keep surfing, there are better articles out there.
Ultimate HDF Member
Joined: Oct 2010
Posts: 5,456
Likes: 2,860
From: SW FL-Jersey Shore Emigre
I think you need to go back to physics 101 if you think that is a good reference.
He doesn't know how to balance forces, and like someone quoted him saying different parts of the tire are rotating at different RPM!! Haha. Too funny.
Seriously though, it's a lot of empirical info and the guy tried to embellish with quasi scientific terms.
Keep surfing, there are better articles out there.
He doesn't know how to balance forces, and like someone quoted him saying different parts of the tire are rotating at different RPM!! Haha. Too funny.
Seriously though, it's a lot of empirical info and the guy tried to embellish with quasi scientific terms.
Keep surfing, there are better articles out there.
Elite HDF Member
Joined: Aug 2011
Posts: 3,932
Likes: 45
From: Stockbridge GA
This guy does a good job but the formulas make my brain hurt. 
http://www.stevemunden.com/leanangle.html
http://www.stevemunden.com/leanangle.html
Road Captain
Joined: Jul 2014
Posts: 717
Likes: 15
From: San Dimas
Uh, no... but that would be better refuted in a separate thread. The last part of this statement is dead-on, but trail braking is an essential skill in motorcycling-- especially if one visits the twisty bits on a regular basis.
Why people gotta be hatin?
Fuq it, lets ride!
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Verdad Gallardo
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
10 Things Harley-Davidson Needs to Fix in 2026
Verdad Gallardo
Big Kahuna HDF Member
Joined: Nov 2008
Posts: 35,506
Likes: 27
From: Calgary eh
It is a good site that explains "Two Wheel Physics" in laymans terms. It was not done by a conglomerate trying to sell you tires, just a guy who knows a bit and shared it. There are mistakes but in general it's spot on. If you don't like it feel free to move on. I for one enjoyed the read.
Why people gotta be hatin?
Fuq it, lets ride!
Why people gotta be hatin?
Fuq it, lets ride!
Just to be clear, I'm not hatin. Just trying to do a community service, stating that the article is not factually correct.
Actually it's flat out wrong on a lot of points. And I see what he's trying to say but his premise is wrong. He's saying if the bike weighs 600 lbs and you take it into a sharp corner the apparent weight increases due to "centrifugal" force. Then because the bike weighs more there is more friction between your tires and the road.
Why is this wrong? Because on a flat road the weight of the bike will always be 600 lbs. What you're feeling when you go through a corner is the force of the road pressing against your leaning bike which increases your apparent weight. This is exactly the same effect as what you feel in a car when you go around a corner on a banked curve. When the car (or bike) is banked you don't feel the lateral pull (which is inertia, not centrifugal force). The component of force that pulling you sideways in a curve is transferred to an apparent vertical force increasing your weight. But, in the case of a motor bike on a flat road the component of force normal to the road (down) is still 600lbs.
I hope that makes sense.
A classical problem in first year undergraduate physics is to derive the equation for the relationship between Mass, velocity, radius of curvature, and angle of the road. You have to assume the coefficient of friction is 0 (slippery like ice). In other words, you're going 50mph, the corner radius is 500 ft, what's the angle of the road so you don't slip off either side.
Anyway, it's good to think about friction and cornering and riding safety. You don't need to know the equations, you just need to now how fast is too fast.
Ride safe.
Just to be clear, I'm not hatin. Just trying to do a community service, stating that the article is not factually correct.
Actually it's flat out wrong on a lot of points. And I see what he's trying to say but his premise is wrong. He's saying if the bike weighs 600 lbs and you take it into a sharp corner the apparent weight increases due to "centrifugal" force. Then because the bike weighs more there is more friction between your tires and the road.
Why is this wrong? Because on a flat road the weight of the bike will always be 600 lbs. What you're feeling when you go through a corner is the force of the road pressing against your leaning bike which increases your apparent weight. This is exactly the same effect as what you feel in a car when you go around a corner on a banked curve. When the car (or bike) is banked you don't feel the lateral pull (which is inertia, not centrifugal force). The component of force that pulling you sideways in a curve is transferred to an apparent vertical force increasing your weight. But, in the case of a motor bike on a flat road the component of force normal to the road (down) is still 600lbs.
I hope that makes sense.
A classical problem in first year undergraduate physics is to derive the equation for the relationship between Mass, velocity, radius of curvature, and angle of the road. You have to assume the coefficient of friction is 0 (slippery like ice). In other words, you're going 50mph, the corner radius is 500 ft, what's the angle of the road so you don't slip off either side.
Anyway, it's good to think about friction and cornering and riding safety. You don't need to know the equations, you just need to now how fast is too fast.
Ride safe.
Actually it's flat out wrong on a lot of points. And I see what he's trying to say but his premise is wrong. He's saying if the bike weighs 600 lbs and you take it into a sharp corner the apparent weight increases due to "centrifugal" force. Then because the bike weighs more there is more friction between your tires and the road.
Why is this wrong? Because on a flat road the weight of the bike will always be 600 lbs. What you're feeling when you go through a corner is the force of the road pressing against your leaning bike which increases your apparent weight. This is exactly the same effect as what you feel in a car when you go around a corner on a banked curve. When the car (or bike) is banked you don't feel the lateral pull (which is inertia, not centrifugal force). The component of force that pulling you sideways in a curve is transferred to an apparent vertical force increasing your weight. But, in the case of a motor bike on a flat road the component of force normal to the road (down) is still 600lbs.
I hope that makes sense.
A classical problem in first year undergraduate physics is to derive the equation for the relationship between Mass, velocity, radius of curvature, and angle of the road. You have to assume the coefficient of friction is 0 (slippery like ice). In other words, you're going 50mph, the corner radius is 500 ft, what's the angle of the road so you don't slip off either side.
Anyway, it's good to think about friction and cornering and riding safety. You don't need to know the equations, you just need to now how fast is too fast.
Ride safe.
ZZZZZzzzzzzZZZZZZzzzzz....<snort>, uh...oh, what? Oh, thanks for the physics lesson professor. I am sure once we all digest what you posted we will all be better people for it.
J/K
Kidding aside, I didn't take physics and most people here didn't. What I liked most from the site was the explanation (using a cone) of how a bike can turn when the front tire is pointed straight, the rest was just gravy. I was also undet the impression that when turning we were exponentially losing traction when in fact we are not lossing any (save for gravel and oil, not relevant to my point). I didn't expect the nitpicking but at the end of the day, it doesnt' bother me either. Just wait until someone spells definitely with an E....I will be on that like white on rice.