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Attack Angle Constant Radius Calculator If you are making a turn and encounter an obstacle, you can determine what the maximum attack angle your bike will achieve given you can determine the radius of the turn, and how far you travel in a vertical and horizontal distance from the start of the curve using this calculator. 
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03/03/2012 6:36 PM by: James R. Davis 
James R. Davis 


Average Deceleration Rate Calculator Though not an excel model, this chart provides you the ability to directly determine the average deceleration rate during a quick stop when you have the speed traveled when braking began and the distance taken to bring the bike to a complete stop. 
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11/24/2010 9:32 AM by: James R. Davis 
James R. Davis 


Average Deceration Rate From Max Rate and Squeeze Time Assuming that you have been practicing quick stops during your parking lot practice sessions, you have determined your average rate of deceleration during those efforts by measuring the distance needed to stop and knowing how fast you were going when you started braking. You even found out what your maximum deceleration rate was given that you could estimate your 'squeeze time'. This model will tell you your average deceleration rate at any higher starting speed given the same squeeze time and maximum deceleration rate. 
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05/08/2012 1:26 PM by: James R. Davis 
James R. Davis 


Bike Weight by Latitude This calculator provides you the ability to determine your bike's weight given you know what it's mass is and where it's located on the earth (latitude and altitude). 
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07/03/2012 11:11 PM by: James R. Davis 
James R. Davis 


Distance To Avoid Calculator Ever wondered how long it would take you to change lanes at a given speed, or how much distance your motorcycle would travel (how much distance you NEED) in order to swerve to the left or right a given number of feet at a particular speed, or how aggressively you need to change directions to avoid hitting something in the road? This calculator will give you the answers. 
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03/03/2012 5:00 PM by: James R. Davis 
James R. Davis 


Effective Steering Angle Calculator The amount of rotation you provide your handlebar is not the same as the amount of turning your bike will do. That is, your steering angle is not the angle your motorcycle changes direction by. The effective steering angle is a function of your head steering angle, your rake angle, and the lean angle of the bike. This calculator will compute the effective steering angle from those inputs. 
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03/03/2012 6:05 PM by: James R. Davis 
James R. Davis 


Impact Speed Some of the simplest models can enlighten us with solutions to difficult problems. This model can be used to determine how fast you will hit the ground and how long it will take to strike the ground given the distance fallen. Maybe more importantly, let's say a student pops her clutch with a 1/4 throttle application and she travels 40 feet before running into a concrete lamp pole. Assuming that 1/4 throttle generates an acceleration rate of 0.4g's (or whatever you wish), this model will tell you how fast she was going at the time of the crash and how long it took. 
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04/14/2013 10:01 PM by: James R. Davis 
James R. Davis 


Kinetic Energy The energy of motion. When an object has motion, it has energy. Just how much is a function of its mass and its speed (squared). This model will quantify that energy for you. 
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04/15/2013 12:03 AM by: James R. Davis 
James R. Davis 


Lateral Acceleration From Lean Angle Simple conversion program that translates any given lean angle into the lateral acceleration (expressed in g's) that MUST correspond. 
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03/03/2012 5:47 PM by: James R. Davis 
James R. Davis 


Lateral Movement Constant Radius You are riding on a circular path with a constant radius. If you suddenly lost traction, your bike would travel in a straight line that is a tangent to the path you were riding. If you maintained your speed and knew how far you traveled in that straight line, how far would you be from the path you were originally traveling?
Or, while remaining on your original circular path, how far do you move laterally if you know how far you moved longitudinally?

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03/03/2012 6:27 PM by: James R. Davis 
James R. Davis 


Lean Angle From Lateral Acceleration Simple conversion program that translates any given Lateral Acceleration (expressed in g's) into the lean angle that MUST correspond. 
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03/03/2012 5:52 PM by: James R. Davis 
James R. Davis 


Longitudinal Movement Constant Radius This calculator will provide you the longitudinal distance traveled if you know both the lateral distance and length of radius when you are riding in a circular path at constant speed. 
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03/03/2012 6:50 PM by: James R. Davis 
James R. Davis 


Maximum Lateral Movement Ever wondered how far you could veer to the left or right in a given distance? You would need to know how much distance you had in front of you and how aggressively you steered. This model will do the calculations for you. 
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01/14/2012 12:26 PM by: James R. Davis 
James R. Davis 


Segment (arc) Length Calculator When traveling between two points along the circumference of a circle, given the central angle and radius of that path, this calculator will determines the actual distance traveled. 
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03/03/2012 6:54 PM by: James R. Davis 
James R. Davis 


Squeeze Time Effect On Max Deceleration The amount of time it takes you to reach your maximum deceleration rate (your squeeze time) affects the maximum deceleration rate you must achieve in order to average a given deceleration rate. This calculator shows you exactly how much. 
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05/02/2012 10:36 AM by: James R. Davis 
James R. Davis 


Traction Demand In order to determine whether your bike will skid or slide, you need to know what the Static Coefficient of Friction is between the tires and roadway as well as the braking and cornering forces that put a demand on traction. Since braking forces are perpendicular (orthogonal), they do not simply add  you must combine them. This simple model demonstrates these facts and gives you a close approximation of total traction demand as compared to the total available traction. 
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05/09/2012 2:03 PM by: James R. Davis 
James R. Davis 


Trail There are two trail measurements: Ground and Mechanical(Real).
This calculator will tell you how long each is given the rake angle, offset, and wheel radius. 
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03/03/2012 5:59 PM by: James R. Davis 
James R. Davis 


Deceleration Rate From Speed and Stopping Distance Given the starting speed and distance to stop, this model calculates the deceleration Rate employed. 
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09/09/2010 1:36 PM by: James R. Davis 
James R. Davis 


Stopping Distance From Speed and Deceleration Rate Given the starting speed and deceleration rate, this model calculates the stopping distance. 
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09/09/2010 1:43 PM by: James R. Davis 



Speed From Stopping Distance Calculator Used to compute how fast a vehicle is traveling at the start of a known stopping distance. It assumes that all braking is done with a constant deceleration rate (such as would generally be the case if skidding). It also allows you to include PDR (PerceptionDecisionReaction) time, if any. 
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06/19/2008 9:58 AM by: James R. Davis 
James R. Davis 


Stopping Distance Calculator This model calculates the fastest possible nonskid stop time and distance given Speed, Grade, Coefficient of Friction, and Braking Efficiency. It also calculates the maximum decelerate rate possible given the height of the CG, length of Wheelbase, and weight distribution. 
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02/02/2007 3:08 PM by: James R. Davis 
James R. Davis 


Speed Scrubbed During Skid It is not intuitive, but skid marks do not represent speed. Instead, they represent energy transformation. That is, they represent the amount of kinetic energy that was converted to heat. This model calculates the amount of speed that is scrubbed during a skid based on the starting speed and drag factors. 
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12/13/2009 11:27 AM by: James R. Davis 
James R. Davis 


Critical Speed Calculator This model calculates the speed at which a vehicle will lose traction given the radius of a curve and the Coefficient of Friction of the roadway. This is usually called the 'Critical Speed'. 
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05/27/2008 11:38 PM by: James R. Davis 
James R. Davis 


Distance traveled and Speed after braking using Decel rate This model allows you to specify your starting speed, deceleration rate, and length of braking time in order to determine how much distance was taken and what the current speed is after that braking time elapses. 
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10/13/2010 6:04 PM by: TonicBIA 
James R. Davis 


Lateral Acceleration & Lean Calculator Given the radius of a turn and the speed of the motorcycle, this model calculates what the lateral acceleration and lean angle of the bike will be. 
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05/27/2008 11:34 PM by: James R. Davis 
James R. Davis 


Quadratic Equation Solver Whenever you can reduce an equation so that it takes on the following standard form:
Ax^{2} + Bx + C = 0
then you can use the quadratic equation solver to solve it. Note, there are ALWAYS two correct solutions for x! 
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05/29/2008 5:18 PM by: James R. Davis 
James R. Davis 


Radius Calculator This simple model allows you to calculate the radius of a curve given the length of a chord and its middle ordinate. 
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05/27/2008 8:54 PM by: James R. Davis 
James R. Davis 


Skid Distance To Stop Sometimes you just want to calculate how long a skid mark will be given a starting speed, the Drag factor components, and the assumption that you come to a complete stop without falling over or colliding with something. 
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12/13/2009 10:09 AM by: James R. Davis 
James R. Davis 


Vault Speed Calculator This model will calculate the speed an object (such as a motorcyclist) is launched at (in other words, the motorcyclist's speed at time of impact) given you know how far it is thrown, the difference in height between launch point and impact point, and the launch angle. 
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06/18/2008 12:01 PM by: James R. Davis 
James R. Davis 


Center of Gravity Calculator This model calculates the location of your Center of Gravity given as input the measured results of lifting the rear wheel off the ground. 
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02/02/2007 3:35 PM by: James R. Davis 
James R. Davis 


Lean Angle Calculator This Excel spreadsheet will calculate the lean angle of the CG of your bike and the lean angle of the combined rider and bike CG given nine different input specifications. Finally, it provides a graph of lateral forces divided by vertical loads based on acceleration rates (if any) so that you can estimate when traction would be lost. 
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02/02/2007 3:43 PM by: James R. Davis 
James R. Davis 


Skid Mark Analyzer This model calculates minimum speed at the time brakes were applied given the input of skid length, Coefficient of Friction, Grade, Braking efficiency, Collision speed (if any), surface moisture (if any), and Transient Braking Time. 
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02/02/2007 2:49 PM by: James R. Davis 
James R. Davis 


Speed by Gear Calculator This simple model calculates your motorcycle speed given the rear tire radius, final gear ratio, and engine RPM. Note that though you have to input seven values with this model, if you merely combined this model with two others (Rear Wheel Radius, and Gearing) you wouldn't need to enter anything. 
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02/04/2007 2:23 PM by: James R. Davis 
James R. Davis 


Rear Wheel Radius Calculator This simple model converts the specification of your rear tire into the radius of the rear wheel. (This is necessary in order to convert wheel RPM into motorcycle speed.) 
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02/03/2007 10:50 PM by: James R. Davis 
James R. Davis 


Horsepower Calculator This simple model calculates your engine's horsepower given its RPM and Torque as input. 
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02/03/2007 11:26 AM by: James R. Davis 
James R. Davis 


Gearing Calculator This model computes the final gear and final drive ratios given the gear tooth counts for Primary Drive, 1st through 6th, and Final Drive as input. 
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02/03/2007 11:18 AM by: James R. Davis 
James R. Davis 


Drag and Lift Calculator This model calculates the weight on the front and rear tires resulting from virtually all variables that could affect them in a dynamic state. In particular, you will provide static state configuration information then add such variables as Latitude, Altitude, Wind speed, and Temperature. 
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02/02/2007 3:20 PM by: James R. Davis 
James R. Davis 

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