[renault_megane_dci]

http://ecomodder.com/forum/showthrea...t-21853-2.html

Originally Posted by renault_megane_dci

Today was coast down test day.

We rode to the "quiet back road" my colleague mentionned.
It was rather windy ...
So I went for a ride, trying to pass his parked car at 100 Km per hour, pulling the clutch and then cheking the speed at a distance, namely a sign on the side.

With the kammback : two attempt showed 62 ish Km per hour

Without the kammback, the bike was easier to maintain at speed (probably more throttle, maybe less wind) and I got a consistant 60 ish Km per hour.

Then I fitted the kammback back but we didn't do more attempts.

All in all : waste of gas ...

I don't know the distance from point A to point B either just the tiny difference in speed

Can I work out something out of it ?

Originally Posted by janvos39

The kinetic energy at 100 km/hr is 0.5*m*v*v and that is with a bike+rider of for instance 250 kg 0.5*250*27.77*27.77=96450 in both tests
This kinetic energy at 60 km/hr is 0.5*250*16.66*16.66=34722
So without the tail enengy consummed by air and roll resistance is 96450-34722=61728

Now with the tail. Energy left at 62 is 0.5-250*17.22*17.22=37076
So energy consummed in this case is 59374. (so approx. 4% less)