Yamaha YB50, Service Manual

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SPEC
MAINTENANCE SPECIFICATIONS
2-4
Model YN50R
Automatic centrifugal clutch:
Thickness of clutch shoe 2 mm
<Limit> <1 mm>
Free length of clutch shoe 29.9 mm
spring
Clutch revolutions 3.600±250 rpm
Clutch binding revolutions 5.600±400 rpm
Transmission:
Main axle deflection limit 0.08 mm
Drive axle deflection limit 0.08 mm
Choke handle:
Type Ratchet type
Pedal friction force 150 ~ 250 g
Air filter oil grade (oil filter):
Oil for foam air filter
2T oil for air-cooled engines
Carburettor:
Type/Manufacturer/Quantity PHVA/Dellorto/1 YP12/GURTNER/1
Main jet (M.J.) #78/5AD #65//SA15 #74/5AD #62/SA15 #60/SA19
Retaining position of jet
needles (J.N.) A12-3/5 A20-3/5 B10A-2/3 B10A-2/3 L3035H-1/3
Main air jet (M.A.I.) ø 1.5 ø 1.5 – – –
Pilot jet (P.J.) #36/5AD #36/SA15 #38/5AD #38/SA15 #36/SA19
Pilot air screw (P.A.S.) 1
1
/
4
±
1
/
4
2
1
/
8
±
1
/
8
1
1
/
8
1
7
/
8
1
7
/
8
Valve seat size 1.2 1.4
engine idling 1.800 r.p.m. 1.800 r.p.m