WORKING-CLASS HERO

Euro 5 environmental rules meant the MT-09 was always due an update for 2021, but Yamaha have gone much further – this may be recognisably an MT-09, but it's more or less a completely new bike.

Starting with the engine, an extra 3mm on the stroke takes capacity up by 42cc to 889cc, and along with revised camshafts offers a few extra horses, but more importantly 7% more torque, delivered 1500rpm lower in the rev range. A heavier crankshaft gives more of a flywheel effect, making it a bit less snappy than before. New, lighter pistons are joined to that crankshaft by connecting rods that are each cast in one piece before being snapped to make a two-piece bearing to bolt round the crank (this allows a lighter casting, and fewer machining processes). The fuel injection system is heavily revised, with new injector banks squirting fuel more or less directly on to the tops of the intake valves, rather than further upstream in the inlet tracts. First and second gears become slightly taller, to damp out the previous model’s often criticised snappiness from low revs. The clutch is revised too, with