How to calculate maximum initial acceleration of the motorcycle?

Discussion in 'High Speed' started by SamZ, Jan 12, 2017.

  1. SamZ

    SamZ New Member

    Motorcycle Specifications:-
    Top speed:- 170 Km/h
    0-100 Km/h Time:- 3.5 Sec
    Motor Used:- 20KW Cont / 50KW Peak // ~50Nm Continuous / 120Nm Peak
    Tire Size:- 120/70-17 front and 160/60-17 rear
    Motorcycle weight:- 190 Kg
    Motor sprocket - 11T
    Wheel sprocket - 64T

    Assuming the rider weight as 60Kgs, calculate the maximum initial acceleration of the motorcycle?
     


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  3. kishore reddy

    kishore reddy New Member

    Given,

    Motor peak torque, Tmax =120 N-m

    At the starting conditions, the motor delivers maximum torque to the wheels

    Gear ratio, G= 64/11 = 5.818

    The torque at the rear wheel = Tmax*G= 120*=698.16 N-m

    Distance of the wheel center from the ground = Rim radius + height of the tyre

    = (17/2*2.54) + (160/10 * 0.6)

    = 31.19 cm = 0.312 m


    Torque = Force * Perpendicular Distance

    Force = 698.16/.312


    F= 2237.69 N


    For maximum initial acceleration, assume full weight on the rear wheel i.e., 190+60 = 250kg

    From newtons 1st law of motion, F=ma

    ð a= 2237.69/250

    ð a=8.95 m/s2

    Hence the maximum initial acceleration approximately .912g.