I popped them out and the RH side (throttle side) looked a bit rusty on the inside. Cleaned out the inside of the bars and replaced the ends with new ones from Suzuki.
They didn't cost that much, but big visual improvement. Just need to change the chain now.
I've got some interesting corrosion on the engine casing near the rear brake lever. Dealer has photographed for Suzuki, just need to wait now until they decide if they'll replace it under warranty (although warranty now expired). Will keep you posted.