I took my Yashica Minister on a weekend motorcycle trip in 2012 and had to realign my rangefinder afterwards (thankfully, a super easy thing to do on that camera). I now give more thought to how I isolate my cameras while riding.
The one thing I'd recommend, especailly if it will be on your tank, is put a good vibration reducing layer underneather it. Thick bubble wrap, two or three layers of regular bubble wrap, some other air bladder, gel, maybe thick memory foam, whatever; lots of options, just not hard foam.
Motorcycles transfer a lot of vibration through their tanks. Ignoring the shock of hitting potholes and frost heaves, even a smooth inline four transfers a lot of vibration when spinning at highway speeds. A good test is to place a glass of water on top of the tank (or where ever you plan on storing your camera) while stationary, and rev it in neutral to cruising
rpm. Watch how much the water shakes, and try your vibration isolation material underneat it.
For this summer's trip I took my AE-1 and rested it on a layer of thick bubble wrap. No issues, but then, the AE-1 is a very different beast from the Minister, so not really an apples to apples comparison.
Have a great trip!