Yamaha YZ250(W)/W1, Owner'S Service Manual

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MAINTENANCE SPECIFICATIONS
SPEC
Item Standard Limit
Clutch housing thrust clearance 0.17~0.23 mm (0.007~0.009 in) …
Clutch housing radial clearance 0.030~0.055 mm (0.001~0.002 in) …
Clutch release method Inner push, cam push …
Transmission:
Main axle deflection limit
…
0.01 mm (0.0004 in)
Drive axle deflection limit
…
0.01 mm (0.0004 in)
Shifter:
Shifting type Cam drum and guide bar
…
Guide bar bending limit
…
0.05 mm (0.0020 in)
Kick starter type: Kick and ratchet type
…
Air filter oil grade (oiled filter): Foam-air-filter oil or equivalent oil
…
Carburetor: USA, CDN EUROPE AUS, NZ, ZA
Type/Manufacturer PWK38S/
← ← …
KEIHIN
I.D. mark 1P89 60 1P86 40 1P87 50
…
Main jet (M.J.) #178 #180 #178
…
Main air jet (M.A.J) #200
← ←
…
Jet needle-clip position (J.N.) N3EW-2 N3EW-3 N3EW-2
…
Main nozzle (N.J.) ø2.9
← ←
…
Cutaway (C.A.) #7
← ←
…
Pilot jet (P.J.) #50 #52 #50
…
Pilot air screw (P.A.S.) 1 2-1/4 1-1/4
…
(for reference only)
Valve seat size (V.S.) ø3.8 mm
← ←
…
(0.15 in)
Starter jet (G.S.) #85
← ←
…
Power jet (P.W.J.) #50
← ←
…
Float arm height (F.H.) 5.5~7.5 mm
← ←
…
(0.22~030 in)
Reed valve:
Thickness* 0.42 mm (0.017 in)
…
Valve stopper height 10.3~10.7 mm (0.406~0.421 in)
…
Valve bending limit
…
0.2 mm (0.008 in)
Cooling:
Radiator core size:
Width 107.8 mm (4.24 in)
…
Height 240 mm (9.45 in)
…
Thickness 32 mm (1.26 in)
…
Radiator cap opening pressure 95~125 kPa
…
(0.95~1.25 kg/cm 2 , 13.5~17.8 psi)
Radiator capacity (total) 0.63 L (0.55 Imp qt, 0.67 US qt)
…
Water pump:
Type Single-suction centrifugal pump
…
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