Honda CRF250F 2023 Owner's Manual page 155

Specifications
Engine Specifications
Valve clearance
(cold)
Spark plug
(standard)
Spark plug gap
Idle speed
(non-adjustable)
146
Technical Information
Intake: 0.004 ± 0.001 in
(0.10 ± 0.02 mm)
Exhaust: 0.006 ± 0.001 in
(0.15 ± 0.02 mm)
LMAR7H-9DS
0.03–0.04 in
(0.8–0.9 mm)
1,400±100 rpm
Power Transmission
Primary reduction 2.863
Gear ratio, 1st 2.846
2nd 1.900
3rd 1.400
4th 1.083
5th 0.896
Final reduction 3.846
Final drive chain