Rato R2000IS, Maintenance Manual, Page: 17 / 64

MAINTENANCE
10
Please measure the clearance after engine cool-down.
Ÿ Adjust valve clearance.
Adjustment steps: loosen the tighten bolt, turn the adjustment nut to a proper position, and
tighten the adjustment nut.
Valve clearance
Intake 0.03~0.08mm
Exhaust 0.03~0.08mm
Adjust the bolt Valve clearance
Tighten Decrease
Loosen Increase
Excess valve clearance: Both valves open behind, which will decrease the
time of air intake and exhaust, lower the opening height of valves, make engine has
insufficient air intake and can’t exhaust clearly, and result in power decrease. Besides,
it will increase the hit between relevant parts of valve and increase parts abrasion.
Insufficient valve clearance: In engine working, heat will expand parts which push
valves away, and result in incomplete sealing of valve, power decrease and valve surface
burning, even makes valves hit piston.
Valve
Valve tighten
Screwd
river
Wrench