i have know art and robert way back before i even started riding and i have worked in the shop. their is really more to the separation but its more on a personal level. on the business side art moved so he could focus on more porting, carbs, and motor build ups. while robert is focusing on repairs and parts and mostly sit-down customers that don't know how to take care of their stuff. they are both very knowledgable and are both really good at point out problem over the phone. IMO i would call robert before you call art when it comes to advise and replays back since art does take a little longer to respond back.