hey guys im doin a project on mx!we have to make a poster board with 10 things on it that do with the sport and it has to do with math. i already have the ten subjects but i want ideas of how to do some of them
1.angle of jump
2.distance to make jump
3.speed to make it
4.tire pattern for better grip
5.weight of quad
6.diff. jumps i.e. double tripple table top etc.
7.body stance
8.performance parts
9.wind speed in air
10.gear ratio
how about how many miles or laps you can do on a tank of gas.
you left out suspension, kind of important.
Why are we doing YOUR homework? Draw some pics and use pythagorian theorem and crap to figure out angles of ramps or what not. Tradectory of jump will require the knowledge of physics due to the multiple factors. Good luck w/ your project.
your not doin my homework..i was figuring that most of you are older than me so you could help me do it thats all
Quote from: QT314 on October 20, 2006, 07:17:55 PM
Why are we doing YOUR homework? Draw some pics and use pythagorian theorem and crap to figure out angles of ramps or what not. Tradectory of jump will require the knowledge of physics due to the multiple factors. Good luck w/ your project.
Wow, dont u think that was a bit harsh... Hes just looking for ideas....
Quote from: MadMudder on October 20, 2006, 09:32:55 PM
Quote from: QT314 on October 20, 2006, 07:17:55 PM
Why are we doing YOUR homework? Draw some pics and use pythagorian theorem and crap to figure out angles of ramps or what not. Tradectory of jump will require the knowledge of physics due to the multiple factors. Good luck w/ your project.
Wow, dont u think that was a bit harsh... Hes just looking for ideas....
Oh good lord you ppl need to shut the hell up if you can't take a joke. Were you incapable of reading the rest of my post w/ IDEAS? Dee Dee Dee!
simmer down there QT.
call travis pastrana, he is brilliant when it comes to ramps and jumps and all that. he does all his and stuff. he will help you im sure. he is the man. if you showed up at his front door he would let you do whatever and do it wherever at his house. all you need is his number.
Quote from: Fox17 on October 20, 2006, 11:13:35 PM
simmer down there QT.
call travis pastrana, he is brilliant when it comes to ramps and jumps and all that. he does all his and stuff. he will help you im sure. he is the man. if you showed up at his front door he would let you do whatever and do it wherever at his house. all you need is his number.
THATS WUT I WOULD DO!! LOL
Here's some important formulas that engineer nerd types know for engine building and motorcycles...
You might find them interesting.
Formulas for displacement, bore and stroke
pi/4 = 0.7853982
cylinder volume = pi/4 x bore^2 x stroke
stroke = displacement / (pi/4 x bore^2 x number of cylinders)
Formulas for compression ratio
(CylVolume + ChamberVolume) / ChamberVolume
cylinder volume = pi/4 x bore^2 x stroke
chamber volume = cylinder volume / compression ratio - 1.0
displacement ratio = cylinder volume / chamber volume
amount to mill = (new disp. ratio - old disp. ratio / new disp. ratio x old disp. ratio) x stroke
Formulas for piston speed
piston speed in fpm = stroke in inches x rpm / 6
rpm = piston speed in fpm x 6 / stroke in inches
Formulas for brake horsepower
horsepower = rpm x torque / 5252
torque = 5252 x horsepower / rpm
brake specific fuel consumption = fuel pounds per hour / brake horsepower
bhp loss = elevation in feet / 1000 x 0.03 x bhp at sea level
Formulas for indicated horsepower & torque
horsepower = mep x displcement x rpm / 792,00
torque = mep x displacement / 150.8
mep = hp x 792,000 / displacement x rpm
mep = hp x 792,000 / displacement x rpm
mechanical efficiency = brake output / indocated output x 100
friction output = indicated output - brake output
taxable horsepower = bore2 x cylinders / 2.5
Formulas for air capacity & volumetric efficiency
theoretical cfm = rpm x displacement / 3456
volumetric efficiency = actual cfm / theoretical cfm x 100
street carb cfm = rpm x displacement / 3456 x 0.85
racing carb cfm = rpm x displacement / 3456 x 1.1
Formulas for tire size & their effect
effective ratio = (old tire diameter / new tire diameter) x original ratio
actual mph = (new tire diameter / old tire diameter) x actual mph
Formulas for g force & weight transfer
drive wheel torque = flywheel torque x first gear x final drive x 0.85
wheel thrust = drive wheel torque / rolling radius
g = wheel thrust / weight
weight transfer = weight x cg height / wheelbase x g
lateral acceleration = 1.227 x raduis / time^2
lateral weight transfer = weight x cg height / wheel track x g
centrufugal force = weight x g
Formulas for shift points
rpm after shift = ratio shift into / ratio shift from x rpm before shift
driveshaft torque = flywheel torque x transmission ratio
Formula for instrument error
actual mph = 3600 / seconds per mile
speedometer error percent = difference between actual and indicated speed / actual speed x 100
indicated distance = odometer reading at finish - odometer reading at start
odometer error percent = difference between actual and indicated distances / actual distance x 100
Formulas for MPH RPM gears & tires
mph = (rpm x tire diameter) / (gear ratio x 336)
rpm = (mph x gear ratio x 336) / tire daimeter
gear ratio = (rpm x tire diameter) / (mph x 336)
tire diameter = (mph x gear ratio x 336) / rpm
Formulas for weight distribution
percent of weight on wheels = weight on wheels / overweight x 100
increased weight on wheels = [ distance of cg from wheels / wheelbase x weight ] + weight
Formulas for center of gravity
cj location behind front wheels = rear wheel weights / overall weight x wheelbase
cg location off-center to heavy side = track / 2 - [ weight on light side / overall weight ] x track
cg height = [ level wheelbase x raised wheelbase x added weight on scale / distance raised ] x overall weight
I concur, with one small caveat! When calculating cg location off-center to heavy side, one must take into account whether the rider has a club foot or ate tacos for their pre-race meal! Other than that, spot on.