Might make a difference
Try doing the same gear shifting w/o your helmet.
Not suggesting your make this a habit but I do it when trying to get a better study on a mystery sound.
Have you relocated some of your cargo, during your trip ? Wind wipping in & out of objects can make sounds. Have you snugged the exhaust header nuts ?
Check fluid levels or at least for wet spots at underside.
Do not know your route, but my BRO is in NE FL, has a great pasture or a bed/bath up stairs & way to many tools for one guy....fact some of them are mine.