math project on mx need help!

[k.p.]

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

[Sleazy_Rider78]

how about how many miles or laps you can do on a tank of gas.

[arod]

 you left out suspension, kind of important.

[qt314nfla]

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.

[k.p.]

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

[MadMudder]

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....

[qt314nfla]

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!

[Fox17]

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.

[rancher4lyfe]

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

[UncleRico]

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

[dnigels]

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.