2009-2010 Suzuki DF70A DF80A DF90A Outboard Service Manual, Page 35Get this manual
Maintenance and Tune-Up: Adjustment Tappet clearances are adjusted by replacing tappet shim1) With cam nose vertical to valve, turn tappet cut-away towards center of cylinder head as shown in figure 0B-9
4) Rotate top of cam 90 degree counterclockwise and remove shim from cut- away at tappet(Two tappets can be adjusted at the same time)
I9J011020009-01
I9J011020011-01
1Shim 3Magnet
"A": Cut section of the tappet "B": Spark plug hole