Fortunatelly the firemen told me it was not dangerous but still it was a bit scary.
forget the fireman call Ripley’s, it’s a snake on nitro! 
Wow. I have never seen a snake act like that. Scary. Nice tracking though.
Thank you slitharg.
It could be better. I had a better snake movement when it had no head by applying a wave modifier (zero velocity and fixed to an empty) to a bezier which had a circle as bevel object and a curve as taper to reduce the thickness till the end of the body. With that the wave modifier was influencing a few points of the bezier and the movement was perfect but in order to put the head of the snake I converted the previous model to mesh and then as the wave was influencing every vertice and the wave is not a perfect sinusoide, in one side of the movement it is ok but in the other it looks sharper, that’s the reason why the movement is a bit fast so we can’t figure it out at the first sight.
I could probably keep the previous model and fix the head with hooks to some vertices and the discontinuity would probably not be seen but I had no time to get it ready for April 1st.