How MotoGP Launch Control Works

Launch control is the rider-aids programme designed to help MotoGP riders when they rocket away from the grid at the start of races. This is how it works

 

This is what makes the start of a race more important than ever and this is why launch control was invented. Launch-control programmes are designed to help the rider use maximum acceleration when he dumps the clutch on 260 horsepower. But like all MotoGP rider aids, Dorna’s recently introduced unified software is significantly less clever than the tailormade software created by the factories during the first decade or so of MotoGP.

Dorna’s idea was to reverse rider-aid technologies to their original concept – to improve safety, rather than increase performance. Magneti Marelli have applied that concept to launch control as well as the other four rider aids: traction control, anti-wheelie, engine-braking control and anti-jerk.

During the era of factory electronics, launch control became so effective that riders could use full throttle and dump the clutch when the red starter-lights were extinguished. Without rider aids, this behaviour would’ve spelt instant disaster: a dead-cert loop-the-loop. But the factory software was clever enough to have the situation under control, supplying exactly the right amount of power to the rear tyre, so the rider could race towards the first turn fully in control with the front wheel no more than a few inches off the ground.

Eventually most of the factories had similarly effective launch control, so it could be argued that this actually reduced safety, because all the riders arrived at the first corner at the same time.

Now riders must do most of the work themselves, which most people think is the way it should be, because rider skill is better rewarded.

You may have noticed that many riders do get sideways during race starts, despite launch control; this is because launch control doesn’t operate the traction-control system, it only operates anti-wheelie.

 

Number 1

White rectangle is LC (launch control) actuation

This signifies the rider pressing a button on the left handlebar to actuate the LC strategies. The system switches out of LC the moment the rider starts decelerating into the first corner. LC also adjusts the rev limiter, so the rider can fully open the throttle without danger of over-revving, and therefore concentrate solely on throttle/clutch balance.

Number 2

Red trace is throttle opening

Many riders blip the throttle before the red lights go out to start a race, but they do it for no real reason. Nervous riders tend to play with the gas more!

Number 3

White trace is bike speed. Red trace is rear-wheel speed. Green trace is front-wheel speed

The rider has made a good getaway, without the front wheel lifting immediately and with minimal wheelspin. But that won’t last. The front wheel lifts slightly, decelerating immediately, which correlates with the rider hesitating with the throttle (see top section). The wheel lands for a moment and then lifts much higher when the rider shifts into second. Meanwhile the red trace moves above the white trace and stays there, denoting wheelspin, with a spike at each gear shift, which continues unabated until the rider slows for the first corner. LC does not feature traction control because the fewer control strategies working at any point, the better. Also, straight-line wheelspin isn’t potentially dangerous to a MotoGP rider – he should be able to control it with his throttle hand.

Number 4

White trace is torque request from rider. Green trace is torque delivery to engine. Red trace is calculated wheelie limit

The downward spikes illustrate the anti-wheelie drastically reducing engine torque delivery to minimise wheelies each time the rider changes gear, into second, third and fourth.

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