* First Step is to drain the oil, you can do it without draining oil, but more messier !!

* Next remove the airscoops, then remove at least one plug from each cylinder (all of them if you intend to change them at this time as well).

* Remove the remaining screws from the rocker covers with 3/16" allen key, be carefull with the rubber seals.

Head Torque 24ftlbs (32Nm)
* One of the head bolts is concealed behind a 3/16" allen head plug on each cylinder, see picture above. You will need to screw out the 3/16" plug to gain access to the 1/4" hex head bolt.

* Head bolts that require torquing are shown with a red circle on picture, the two middle ones require a 1/2" Socket, the others are all 1/4" Allen dive.

* Torque all bolts on each head to above torque.

* VERY IMPORTANT, REMEMBER TO REFIT THE 3/16" PLUG.

Valve Clearance Setting
* Start on No.1 cylinder, turn the prop until one of the valves on that cylinder is fully depressed (open), Note where the prop is and turn it a full 360deg. This will leave this Valve fully open. Adjust the gap by loosening the 9/16" nut and turning the adjuster with a flat blade screwdriver until the feeler gauge is a nice sliding fit at .010" (.25mm). Lock up the 9/16" nut.

* Repeat for all the other valves.

* Check you have fitted the 3/16" plug above and clean around the rockers and the rocker covers and refit them, torque for the cap head screws is 7Nm (5ft/lbs).

* Clean/Replace your plugs and set the gap to .022 (.55mm).

* Refit the air scoops

* Refill the engine with oil if drained along with a new oil filter. Wire lock sump plug.