Yamaha YFM660 01 User Manual

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GEN
INFO
SPECIAL TOOLS
90890-01469
YM-01469
Oil filter wrench
This tool is needed to loosen or tighten 
the oil filter cartridge.
90890-01474
YM-01474Ball joint remover/installer set
These tools are used to removing or 
installing the ball joint.
90890-01480
YM-01480Ball joint remover/installer attachment set
These tools are used to removing or 
installing the ball joint.
90890-01701
YS-01880Sheave holder
This tool is needed to hold the AC mag-
neto rotor when removing or installing the 
AC magneto...

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GEN
INFO
SPECIAL TOOLS
Middle driven shaft 
bearing driver
90890-04058
YM-04058-1
Mechanical seal 
installer
90890-04078
YM-33221Middle driven shaft bearing driver
Mechanical seal installer
These tools are used to install the water 
pump seal.
90890-04064
YM-4064-AValve guide remover (ø 6)
This tool is needed to remove and install 
the valve guide.
90890-04065
YM-04065-AValve guide installer (ø 6)
This tool is needed to install the valve 
guide.
90890-04066
YM-04066Valve guide reamer (ø 6)
This...

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SPEC
SPECIFICATIONS
GENERAL SPECIFICATIONS
Item Standard
Model code: 5LP1 : (Except for California)
5LP3 : (For California)
Dimensions:
Overall length 1,830 mm (72.0 in)
Overall width 1,100 mm (43.3 in)
Overall height 1,150 mm (45.3 in)
Seat height 860 mm (33.9 in)
Wheelbase 1,245 mm (49.0 in)
Minimum ground clearance 265 mm (10.4 in)
Minimum turning radius 3,300 mm (129.9 in)
Basic weight:
With oil and full fuel tank 193 kg (426 lb)
Engine:
Engine type Liquid-cooled 4-stroke, SOHC
Cylinder...

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SPEC
Carburetor:
Type/quantity BSR33/2
Manufacturer MIKUNI
Spark plug:
Type/manufacturer DPR8EA-9/NGK
Spark plug gap 0.8 ~ 0.9 mm (0.031 ~ 0.035 in)
Clutch type: Wet, multiple disc
Transmission:
Primary reduction system Spur gear
Primary reduction ratio 71/34 (2.088)
Secondary reduction system Chain drive
Secondary reduction ratio 40/13 (3.076)
Transmission type Constant mesh, 5-speed/forward.
1-speed/reverse
Operation Left foot operation
Gear ratio
1st gear 34/14 (2.428)
2nd gear 29/19 (1.526)
3rd...

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SPEC
Tire pressure (cold tire):
Maximum load* 100 kg (220 lb)
Off-road riding front 27.5 kPa (0.275 kg/cm
2, 4.0 psi)
rear 27.5 kPa (0.275 kg/cm
2, 4.0 psi)
*Load in total weight of cargo, rider and acces-
sories
Brake:
Front brake type Dual disc brake
operation Right hand operation
Rear brake type Single disc brake
operation Right foot operation
Suspension:
Front suspension Double wishbone
Rear suspension Swingarm (link suspension)
Shock absorber:
Front shock absorber Coil spring/oil damper
Rear...

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SPEC
MAINTENANCE SPECIFICATIONS
ENGINE
Item Standard Limit
Cylinder head:
Warp limit ---- 0.05 mm 
(0.002 in)
Cylinder:
Bore size 100.005 ~ 100.045 mm
(3.9372 ~ 3.9388 in)100.1 mm 
(3.94 in)
Measuring point 
*50 mm (2.0 in) ----
Camshaft:
Drive method Chain drive (Left) ----
Camshaft cap inside diameter 23.000 ~ 23.021 mm
(0.9055 ~ 0.9063 in)----
Camshaft journal diameter 22.967 ~ 22.980 mm
(0.9042 ~ 0.9047 in)----
Camshaft journal-to-camshaft cap clearance 0.020 ~ 0.054 mm
(0.0008 ~ 0.0021...

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SPEC
Camshaft runout limit ---- 0.03 mm 
(0.0012 in)
Timing chain:
Timing chain type/No. of links 75-RH2015/126 ----
Timing chain adjustment method Automatic ----
Rocker arm/rocker arm shaft:
Shaft outside diameter 11.976 ~ 11.991 mm 
(0.4715 ~ 0.4721 in)----
Arm-to-shaft clearance 0.009 ~ 0.042 mm 
(0.0004 ~ 0.0017 in)----
Valve, valve seat, valve guide:
Valve clearance (cold) IN 0.10 ~ 0.15 mm
(0.0039 ~ 0.0059 in)----
EX 0.15 ~ 0.20 mm
(0.0059 ~ 0.0079 in)----
Valve dimensions
“A” head diameter...

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SPEC
Stem-to-guide clearance IN 0.010 ~ 0.037 mm 
(0.0004 ~ 0.0015 in)0.08 mm 
(0.0031 in)
EX 0.025 ~ 0.052 mm 
(0.0010 ~ 0.0020 in)0.10 mm 
(0.0039 in)
Stem runout limit ---- 0.01 mm 
(0.0004 in)
Valve seat width IN 0.9 ~ 1.1 mm 
(0.0354 ~ 0.0433 in)1.6 mm 
(0.0630 in)
EX 0.9 ~ 1.1 mm 
(0.0354 ~ 0.0433 in)1.6 mm 
(0.0630 in)
Valve spring:
Free length IN 35.95 mm (1.42 in) 34.15 mm 
(1.34 in)
EX 37.75 mm (1.49 in) 35.86 mm 
(1.41 in)
Set length (valve closed) IN 27.2 mm (1.07 in) ----
EX 30.7 mm...

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SPEC
Piston:
Piston to cylinder clearance 0.05 ~ 0.07 mm 
(0.0020 ~ 0.0028 in)0.15 mm 
(0.0059 in)
Piston size “D” 99.945 ~ 99.995 mm 
(3.9348 ~ 3.9368 in)----
Measuring point “H” 2.5 mm (0.10 in) ----
Piston off-set 1.0 mm (0.04 in) ----
Piston pin bore inside diameter 22.004 ~ 22.015 mm
(0.8663 ~ 0.8667 in)22.045 mm 
(0.8679 in)
Piston pin outside diameter 21.991 ~ 22.000 mm
(0.8658 ~ 0.8661 in)21.971 mm 
(0.8650 in)
Piston rings:
Top ring
Type Barrel ----
Dimensions (B × 
T) 1.2 ×
 3.8 mm...

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SPEC
Crankshaft:
Crank width “A” 74.95 ~ 75.00 mm 
(2.9508 ~ 2.9528 in)----
Runout limit C1 ---- 0.03 mm 
(0.0012 in)
C2 ---- 0.03 mm 
(0.0012 in)
Big end side clearance “D” 0.32 ~ 0.64 mm 
(0.0126 ~ 0.0252 in)1.0 mm 
(0.0394 in)
Big end radial clearance “E” 0.010 ~ 0.025 mm 
(0.0004 ~ 0.0010 in)----
Small end free play “F” 0.8 mm (0.0315 in) ----
Balancer:
Balancer drive method Gear ----
Clutch:
Friction plate 1
Thickness 2.74 ~ 2.86 mm
(0.108 ~ 0.113 in)2.6 mm 
(0.102 in)
Quantity 6 ----
Friction...