The engine has an oil circuit pressure relief valve fitted to the oil pump circuit to regulate oil pressure in line with engine revolutions per minute. This new valve prevents pressure peaks under cold conditions, limits power losses and reduces operating temperatures. A new, more efficient oil filter was also installed. The exhaust valves on all the twin cam models are made of steel (previously titanium) to increase their lifespan. Thanks to its new design, engine top speeds remain unchanged for all engine sizes. The gearbox has been updated to provide faster, more accurate changes with improvements made to the gear change shaft, gearbox lever and selector mechanism. On the 250 as on all the other twin cam models, a new timing chain tensioner has been fitted along with new block gasket.