My wife and I have ninja 500's that have velocity stacks, full m4 exhaust, block off kit, and ecu tune that really opened the bikes up. My question for those that do a lot of interstate driving is can these engines sustain 8000 rpm for long periods or do I need to be changing sprockets soon. Since we got the bikes we've been doing a lot of longer (4 us) trips and eventually want to make our way to the dragon but don't want to blow our engines getting there. Any comments and experiences are appreciated.