Undo and remove the two head fastener screws located in the timing chain compartment.
![](https://motoinstruction.ru/img/aprilia/17/123065.jpg)
Undo and remove the outer screw.
![](https://motoinstruction.ru/img/aprilia/17/123066.jpg)
Undo and remove the four nuts, proceeding in stages and in a diagonal pattern.
Ease the cylinder head assembly off the stud bolts.
Remove the three nuts fastening the cylinder head on the intake and exhaust sides.
![](https://motoinstruction.ru/img/aprilia/17/123067.jpg)
Remove the gasket between the cylinder and the crankcase.
![](https://motoinstruction.ru/img/aprilia/17/123068.jpg)
See also specifications for this operation.