Yamaha MX250, Service Manual

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SPECIFICA
T
IONS
MAINTENANCE SPECIFICATIONS
Warpage limit 80.04 mm (3.1512 in)
Crankshaft:
Big end side clearance 0.20–0.65 mm (0.0079–0.0256 in)
Runout limit 0.8 mm (0.0315 in)
Crank pin outside diameter 33.969–33.984 mm (1.3374–1.338 in)
Limit 33.9 mm (1.3346 in)
Connecting rod:
Small end diameter 19.006–19.020 mm (0.7482–0.7488 in)
Oil clearance 0.006–0.015 mm (0.0002–0.0005 in)
Big end diameter 34.00–34.015 mm (1.3386–1.3392 in)
Oil clearance 0.016–0.046 mm (0.0006–0.0018 in)
Limit 0.09 mm (0.0035 in)
Camshaft:
Camshaft lobe dimensions
Lobe height (Intake) 32.1–32.2 mm (1.2638–1.2677 in)
Limit 31.9 mm (1.2559 in)
Lobe height (Exhaust) 32.5–32.6 mm (1.2795–1.2835 in)
Limit 32.3 mm (1.2717 in)
Base circle diameter (Intake) 25.98–26.08 mm (1.0228–1.0268 in)
Limit 25.78 mm (1.015 in)
Base circle diameter (Exhaust) 26.03–26.13 mm (1.0248–1.0287 in)
Limit 25.83 mm (1.0169 in)
Camshaft journal diameter 15.965–15.990 mm (0.6285–0.6295 in)
Limit 15.950 mm (0.628 in)
Valve:
Valve dimensions
Valve head diameter (Intake) 31.9–32.1 mm (1.2559–1.2638 in)
Valve head diameter
(Exhaust) 28.9–29.1 mm (1.1377–1.1456 in)
Valve stem diameter (Intake) 5.948–5.963 mm (0.2342–0.2348 in)
Valve stem diameter (Exhaust) 5.940–5.955 mm (0.2339–0.2344 in)
Limit (Intake) 5.918 mm (0.2330 in)
Limit (Exhaust) 5.910 mm (0.2327 in)
Valve stem length (Intake) 90.0 mm (3.5433 in)
Valve stem length (Exhaust) 90.3 mm (3.5551 in)
Valve face contact width
(Intake) 0.7–0.9 mm (0.0276–0.0354 in)
Valve face contact width
(Exhaust) 0.7–0.9 mm (0.0276–0.0354 in)
Limit (Intake) 1.4 mm (0.055 in)
Limit (Exhaust) 1.4 mm (0.055 in)
Valve seat contact width
(Intake) 0.7–0.9 mm (0.0276–0.0354 in)