Make sure you have decent gear: rain suit, waterproof boots and gloves, a bike cover (security reasons, primarily), and newer tires. Our first long trip was on a 30-year-old, Honda 750, in 2009. The bike ran flawlessly, but our gear was not adequate, and we suffered hypothermia, riding in four days of rain, in the mid-50's, in Canada. We made it, but it wasn't pleasant during our Canada portion circling Lake Superior.
My wife and I try to get in one long trip each Summer, but we've been unable to do that since two Summer's ago. We live the off-season, sustaining ourselves on past tours on the bikes, as well as planning the next Summer's big trip. It's been a tough time, these past two Winters, and the next Winter is going to be even tougher since we won't get a decent long trip in this Summer.
Our first big tour was not particularly fun, in the cold and rain, but it was our first long tour (nine days), and even though we endured a lot of mistakes, and blunders, it is still our most memorable trip. Looking forward to repeating it on the Voyager in the next few years -- hopefully with better weather!
Make some memories for yourselves which will last the rest of your lives! Enjoy the trip, blunders and all. Cheers!
