Segway SNARLER ATV 2021 Series Service Manual page 138

ENGINE TOP END ENGINE TOP END
◆ Rotate the valve rapidly back and forth until the cut
sounds smooth. Lift the valve slightly off of the seat,
rotate 1/4 turn, and repeat the lapping process. Do
this four to fi ve times until the valve is fully seated,
and the seating surface is smooth, Then repeat
process for the other valve(s).
◆ Thoroughly clean cylinder head and valves.
CAUTION CAUTION
Do not grind the seat too much. Overgrinding will reduce
valve clearance by sinking the valve into the head. If the
valve sinks too far into the head, it will be impossible
to adjust the clearance, and the cylinder head must be
replaced.
3-5-28