Many years ago when Stagecoach ran tri-axle Olympians on the Megabus services, there was one vehicle (13633) which was nicknamed the Geordie Flyer which could hit over 80mph downhill on the M1 towards Meadowhall, one driver I knew (who has sadly since passed) managed to get it up to a high speed on the M1, and amazingly the Olympian took it with ease and just cruised along.