that is maybe copied from the vintage 2CV, my Citroen 2 CV has that too, and there are more 'funny' things on an 2CV
http://www.citroen.mb.ca/documents/motor/motor2cv.html
The 2CV also pioneered the use of the now common Wasted spark Ignition System, also known as the DIS (Distributorless Ignition System) ignition using a double ended coil fired on each revolution, (on the exhaust and compression stroke), by just a contact breaker.
http://en.wikipedia.org/wiki/Citro%C3%ABn_2CV