Top-end stuff!

With all the lockdown nonsense, it’s time for Allen to get on with the motor build of his splendid Kawasaki Super Six.

- Allen Millyard

With the current lockdown related a bit it was really nice to be able to go out for a ride on a few of my bikes, especially my Z1 Super Six. I started by riding it on short trips local to home. I always put the engine through many heat cycles from cold to hot to help the welded cases and other parts normalise and settle down as part of commissioning the bike.

After about 100 miles I removed the tank and tightened the cylinder head nuts, which is an easy job on the Z1 engine because they are all accessible with the cam-cover in place. While the tank was off I checked the throttle linkage on the carbs to see if anything had come loose. There was a slight lumpiness on light throttle openings and a bit of popping in the exhaust at idle; it felt like one cylinder was missing or not running at all. When the throttle was opened past a quarter of a turn it seemed to chime in and run smoothly. The throttle linkage was fine so maybe it could be a blocked pilot jet on one cylinder. I checked the header pipe temperatures with my optical thermometer and header three was much cooler, then the other five. It is possible to remove the float bowls from the carbs while the carbs are mounted on the bike, so I removed number three. It was full of petrol so there was not a flow issue. I then removed the pilot jet and looked up through it at a light and it was definitely blocked. A quick blast with my air-line removed the obstruction.