Desmodromic (type) with four valves per cylinder, operated by eight rocker arms (4 opening rockers and 4 closing rockers) and two overhead camshafts. It is operated by the crankshaft through spur gears, belt rollers and toothed belts.
Desmodromic timing system (fig. 159)

Engine
Performance dataRefitting the cooling system hoses and unions
Position the pump/radiator sleeve (22) and the radiator/radiator sleeve (23).
Fit sleeve (23) and sleeve (22) to their corresponding fittings (n) and (o), and
bring them fully home on collars (p).
Note
Sleeves (23) and (22) must be oriented so that the grooves (q) match the
tabs (r) on fitt ...
Checking the engine timing
Set the engine to the configuration described for the "checking and adjusting
the valve clearances", previously indicated.
Install tool 88765.1188 (G) in the spark plug bore to determine the piston tdc,
the gauges (h) on the tool 88765.1518
And the timing check tool (degree wheel (l) 887 ...
Fuel, lubricants and other fluids
Important
Do not use additives in fuel or lubricants.
Engine oil
A good quality engine oil has special properties. Use only a highly detergent
engine oil with certified se, sf or sg or
higher service ratings as marked on the container.
Viscosity
Sae 15w-50
The other viscosity grades ...