In the new SBS Volume 101 a fan asked for Franky at ages 40 and 60, though given him already being 36 Oda drew him at ages 50 and 70.
Age 50: It’s cold. I’ll add heating to this island.
Age 70: Fixed your bike. Added a cannon though.
Age 50: I’m the robot that will destroy all the ships in the world.
Age 70 I aaaaaaam~ baaaattleshiiiip~ Franki~