Planning a European motorbike trip

2 years ago (maybe 3), my son suggested it would cool to have a bike trip through the Alps...
Time passed and nothing happened, he was too busy, I was too busy. Last year he accused me of being too old! He might be right, I have just had my 60th where wifey and me enjoyed an amazing 6 week fly-cruise starting in Sydney (from home in England), and ending in Singapore via the most amazing sights and cultures of Indonesia and Vietnam with one of the highlights being Hong Kong which I found awe inspiring.
So we've been back just over a month and I thought, what the hell, lets get this bike trip sorted.
Found a delicious Honda Deauville 650 on eBay, treated myself, got shot of the old Yamaha Diversion and have booked French train transfers from Paris to Lyon for us and the bikes late July (much more civilised than screaming down motorways for 7 hours).
Now my son, Phil, has been given the task of planning an itinerary, maybe Lausanne first stop..... more when we have a plan