EN - 4
TECHNICAL DATA
ENGINE
Type .....................single cylinder, 4 stroke
Cooling . Liquid with double radiator and heater fan
Bore ....................................3.94 in.
Stroke ...................................3.01 in.
Displacement ..........................36.6 cu.in.
Compression ratio .........................12,4:1
Starting ................................electric
TIMING SYSTEM
Type ..................double overhead camshaft
chain operated; 4 valve
Valve clearance (with engine cold)
Intake .......................... 0.004 ÷ 0.006 in.
Exhaust ........................0.006 ÷ 0.008 in.
LUBRICATION
Type ....wet sump with cartridge lobes and filters
IGNITION
Type ........................Electronic, inductive
with adjustable advance (digital control)
Spark plug type ...................... NGK CR8EB
Spark plug gap ..................0.027 ÷ 0.031 in.
FUEL SYSTEM
Type .....................Electronic injection feed
PRIMARY DRIVE
Drive pinion gear .............................Z 32
Clutch ring gear .............................Z 75
Transmission ratio ..........................2,343
CLUTCH
Type . oil bath multiple disc clutch, hydraulic control
TRANSMISSION
Type ...................constant mesh gear type
Transmission ratio
(RS)
1st gear ...........................2,615 (z 34/13)
2nd gear ..........................1,812 (z 29/16)
3rd gear ...........................1,350 (z 27/20)
4th gear ...........................1,091 (z 24/22)
5 th gear .........................0,916 (z 22/24)
6 th gear .........................0,769 (z 20/26)
(SM)
1st gear ...........................2,615 (z 34/13)
2nd gear ..........................1,812 (z 29/16)
3rd gear ...........................1,350 (z 27/20)
4th gear ...........................1,091 (z 24/22)
5 th gear .........................0,957 (z 22/23)
6 th gear .........................0,880 (z 22/25)
SECONDARY DRIVE
Transmission sprocket .......................Z 15
Rear wheel sprocket (RS) ....................Z 42
Rear wheel sprocket (SM) ...................Z 38
Transmission ratio (RS) .....................2,800
Transmission ratio (SM) ....................2,533
Transmission chain dimensions ..........5/8”x1/4”
FINAL RATIOS
(RS)
1st gear ...................................17,163
2nd gear ..................................11,894
3rd gear ...................................8,859
4th gear ................................... 7,159
5 th gear ..................................6,016
6 th gear ..................................5,048
(SM)
1st gear .................................. 15,529
2nd gear .................................10,762
3rd gear ...................................8,016
4th gear ...................................6,477
5 th gear ..................................5,679
6 th gear ..................................5,225
CHASSIS
Type .....single frame, in circular sectioned tubes,
in steel; rear chassis in squared sectioned tubes in
light alloy.
FRONT SUSPENSION
Type “Upside-down” telescopic hydraulic front fork
with advanced axle (adjustable in rebound stroke);
tubes ø 45 mm
Leg axis stroke (RS) ...................... 8.27 in.
Leg axis stroke (SM) ......................9.84 in.
REAR SUSPENSION
Type ......progressive with hydraulic single shock
absorber
(preload regulation of spring and hydraulic brake in
compression and extension)
Wheel stroke (RS) ........................10.63 in.
Wheel stroke (SM) ........................11.4 in.
FRONT BRAKE
Type (RS) .................... fixed disc Ø 10.24 in.
with hydraulic control and floating caliper
Type (SM) ..... floating disk ø12.6in. with hydraulic
command and radial fixed calliper
REAR BRAKE
Type .........................fixed disc Ø 8.66 in.
with hydraulic control and floating caliper
QUICK RS-SM_A000PP00695_ed1_06-2015.indd 4 14/07/15 16:38