21 TECHNICAL DATA
236
21.1
Engine
Design
1-cylinder 4-stroke engine, water-cooled
Displacement
692.7 cm³ (42.271 cu in)
Stroke
80 mm (3.15 in)
Bore
105 mm (4.13 in)
Compression ratio
12.7:1
Idle speed
Coolant temperature:
≥
70 °C (
≥
158 °F)
1,600 ± 50 rpm
Control
OHC, intake with cam levers, exhaust controlled by
rocker arm, chain drive
Valve diameter, intake
42 mm (1.65 in)
Valve diameter, exhaust
34 mm (1.34 in)
Valve play, cold
Intake at: 20 °C (68 °F)
0.10 … 0.15 mm (0.0039 … 0.0059 in)
Exhaust at: 20 °C (68 °F)
0.22 … 0.27 mm (0.0087 … 0.0106 in)
Crankshaft bearing
2 roller bearings
Conrod bearing
Slide bearing
Piston pin bearing
Piston pin with
DLC
coating
Pistons
Forged light alloy
Piston rings
1 compression ring, 1 lower compression ring, 1 oil
ring with spring expander