i'm new in Switzerland and just learning about licenses here, but maybe this will help you: http://www.velos-motos-keller.ch/fuehrerschein.htm
If you know any german
It says basically that if you already have B for the A1 license you only have to take 8 lessons, no exams or anything like that. If you have taken the exam for B before April 2003, you automatically also have "A1 limited", which allows you to drive small motorbikes with up to 45 km/h.
I hope this is not way to late