Beta RR 125 LC User manual

ENGINE SPECIFICATIONS
EAS20290
ENGINE SPECIFICATIONS
Engine
Engine type Liquid cooled 4-stroke, SOHC
Displacement 124.7 cm³
Cylinder arrangement Forward-inclined single cylinder
Bore ×stroke 52.0 ×58.6 mm (2.05 ×2.31 in)
Compression ratio 11.20 :1
Standard compression pressure (at sea level) 550 kPa/600 r/min (5.5 kgf/cm²/600 r/min, 78.2
psi/600 r/min)
Minimum–maximum 480–620 kPa (4.8–6.2 kgf/cm², 68.3–88.2 psi)
Starting system Electric starter
Fuel
Recommended fuel Premium unleaded gasoline only
Fuel tank capacity 8.5 L (2.25 US gal, 1.87 Imp.gal)
Fuel reserve amount 1.6 L (0.42 US gal, 0.35 Imp.gal)
Engine oil
Lubrication system Wet sump
Type SAE 10W-30, SAE 10W-40, SAE 15W-40, SAE
20W-40 or SAE 20W-50
Recommended engine oil grade API service SG type or higher, JASO standard
MA
Engine oil quantity
Total amount 1.15 L (1.22 US qt, 1.01 Imp.qt)
Without oil filter element replacement 0.95 L (1.00 US qt, 0.84 Imp.qt)
With oil filter element replacement 1.00 L (1.06 US qt, 0.88 Imp.qt)
Oil filter
Oil filter type Paper
Oil pump
Oil pump type Trochoid
Inner-rotor-to-outer-rotor-tip clearance Less than 0.150 mm (0.0059 in)
Limit 0.23 mm (0.0091 in)
Outer-rotor-to-oil-pump-housing clearance 0.130–0.180 mm (0.0051–0.0071 in)
Limit 0.25 mm (0.0098 in)
Oil-pump-housing-to-inner-and-outer-rotor
clearance 0.06–0.11 mm (0.0024–0.0043 in)
Limit 0.18 mm (0.0071 in)
Relief valve operating pressure 39.2–78.4 kPa (0.39–0.78kgf/cm², 5.7–11.4 psi)
Pressure check location Check bolt on cylinder head body

ENGINE SPECIFICATIONS
Valve opening temperature 80.5–83.5 °C (176.90–182.30 °F)
Valve full open temperature 95.0 °C (203.00 °F)
Valve lift (full open) 3.0 mm (0.12 in)
Radiator core
Width 128.0 mm (5.04 in)
Height 258.0 mm (10.16 in)
Depth 24.0 mm (0.94 in)
Water pump
Water pump type Single suction centrifugal pump
Reduction ratio 19/38 (0.500)
Spark plug (s)
Manufacturer/model NGK/CR8E
Spark plug gap 0.7–0.8 mm (0.028–0.031 in)
Cylinder head
Volume 9.90–10.50 cm³(0.60–0.64 cu.in)
Warpage limit 0.03 mm (0.0012 in)
Camshaft
Drive system Chain drive (left)
Camshaft lobe dimensions
Intake A 30.225–30.325 mm (1.1900–1.1939 in)
Limit 30.125 mm (1.1860 in)
Intake B 25.127–25.227 mm (0.9893–0.9932 in)
Limit 25.027 mm (0.9853 in)
Exhaust A 30.232–30.332 mm (1.1902–1.1942 in)
Limit 30.132 mm (1.1863 in)
Exhaust B 25.065–25.165 mm (0.9868–0.9907 in)
Limit 24.965 mm (0.9829 in)
Camshaft runout limit 0.030 mm (0.0012 in)
Timing chain
Model/number of links DID SCR-0404SV/96
A
B

ENGINE SPECIFICATIONS
2-4
Tensioning system Automatic
Rocker arm/rocker arm shaft
Rocker arm inside diameter 9.985–10.000 mm (0.3931–0.3937 in)
Limit 10.015 mm (0.3943 in)
Rocker arm shaft outside diameter 9.966–9.976 mm (0.3924–0.3928 in)
Limit 9.941 mm (0.3914 in)
Rocker-arm-to-rocker-arm-shaft clearance 0.009–0.034 mm (0.0004–0.0013 in)
Limit 0.074 mm (0.0029 in)
Valve, valve seat, valve guide
Valve clearance (cold)
Intake 0.10–0.14 mm (0.0039–0.0055 in)
Exhaust 0.20–0.24 mm (0.0079–0.0094 in)
Valve dimensions
Valve head diameter A (intake) 19.40–19.60 mm (0.7638–0.7717 in)
Valve head diameter A (exhaust) 16.90–17.10 mm (0.6654–0.6732 in)
Valve face width B (intake) 1.538–2.138 mm (0.0606–0.0842 in)
Valve face width B (exhaust) 1.538–2.138 mm (0.0606–0.0842 in)
Valve seat width C (intake) 0.90–1.10 mm (0.0354–0.0433 in)
Limit 1.6 mm (0.06 in)
Valve seat width C (exhaust) 0.90–1.10 mm (0.0354–0.0433 in)
Limit 1.6 mm (0.06 in)
Valve margin thickness D (intake) 0.50–0.90 mm (0.0197–0.0354 in)
Valve margin thickness D (exhaust) 0.50–0.90 mm (0.0197–0.0354 in)
Valve stem diameter (intake) 4.475–4.490 mm (0.1762–0.1768 in)
Limit 4.445 mm (0.1750 in)
Valve stem diameter (exhaust) 4.460–4.475 mm (0.1756–0.1762 in)
Limit 4.430 mm (0.1744 in)
Valve guide inside diameter (intake) 4.500–4.512 mm (0.1772–0.1776 in)
Limit 4.550 mm (0.1791 in)
Valve guide inside diameter (exhaust) 4.500–4.512 mm (0.1772–0.1776 in)
Limit 4.550 mm (0.1791 in)
Valve-stem-to-valve-guide clearance (intake) 0.010–0.037 mm (0.0004–0.0015 in)
Limit 0.080 mm (0.0032 in)
A
B
C
D

ENGINE SPECIFICATIONS
Valve-stem-to-valve-guide clearance (exhaust) 0.025–0.052 mm (0.0010–0.0020 in)
Limit 0.100 mm (0.0039 in)
Valve stem runout 0.010 mm (0.0004 in)
Cylinder head valve seat width (intake) 0.90–1.10 mm (0.0354–0.0433 in)
Limit 1.6 mm (0.06 in)
Cylinder head valve seat width (exhaust) 0.90–1.10 mm (0.0354–0.0433 in)
Limit 1.6 mm (0.06 in)
Valve spring
Free length (intake) 41.71 mm (1.64 in)
Limit 39.62 mm (1.56 in)
Free length (exhaust) 41.71 mm (1.64 in)
Limit 39.62 mm (1.56 in)
Installed length (intake) 35.30 mm (1.39 in)
Installed length (exhaust) 35.30 mm (1.39 in)
Spring rate K1 (intake) 23.54 N/mm (2.40 kgf/mm, 134.41 lb/in)
Spring rate K2 (intake) 36.58 N/mm (3.73 kgf/mm, 208.87 lb/in)
Spring rate K1 (exhaust) 23.54 N/mm (2.40 kgf/mm, 134.41 lb/in)
Spring rate K2 (exhaust) 36.58 N/mm (3.73 kgf/mm, 208.87 lb/in)
Installed compression spring force (intake) 140.00–162.00 N (14.28–16.52 kgf, 31.47–
36.42 lbf)
Installed compression spring force (exhaust) 140.00–162.00 N (14.28–16.52 kgf, 31.47–
36.42 lbf)
Spring tilt (intake) 2.5°/1.8 mm
Spring tilt (exhaust) 2.5°/1.8 mm
Winding direction (intake) Clockwise
Winding direction (exhaust) Clockwise
Cylinder
Bore 52.000–52.010 mm (2.0472–2.0476 in)
Wear limit 52.110 mm (2.0516 in)
Taper limit 0.050 mm (0.0020 in)
Out of round limit 0.005 mm (0.0002 in)
Piston
Piston-to-cylinder clearance 0.015–0.048 mm (0.0006–0.0019 in)
Limit 0.15 mm (0.0059 in)
Diameter D 51.962–51.985 mm (2.0457–2.0466 in)

ENGINE SPECIFICATIONS
Height H 5.0 mm (0.20 in)
Offset 0.50 mm (0.0197 in)
Offset direction Intake side
Piston pin bore inside diameter 14.002–14.013 mm (0.5513–0.5517 in)
Limit 14.043 mm (0.5529 in)
Piston pin outside diameter 13.995–14.000 mm (0.5510–0.5512 in)
Limit 13.975 mm (0.5502 in)
Piston-pin-to-piston-pin-bore clearance 0.002–0.018 mm (0.0001–0.0007 in)
Limit 0.068 mm (0.0027 in)
Piston ring
Top ring
Ring type Barrel
Dimensions (B ×T) 0.80 ×1.90 mm (0.03 ×0.07 in)
End gap (installed) 0.10–0.25 mm (0.0039–0.0098 in)
Limit 0.50 mm (0.0197 in)
Ring side clearance 0.030–0.065 mm (0.0012–0.0026 in)
Limit 0.100 mm (0.0039 in)
2nd ring
Ring type Taper
Dimensions (B ×T) 0.80 ×2.10 mm (0.03 ×0.08 in)
End gap (installed) 0.10–0.25 mm (0.0039–0.0098 in)
Limit 0.60 mm (0.0236 in)
Ring side clearance 0.020–0.055 mm (0.0008–0.0022 in)
Limit 0.100 mm (0.0039 in)
Oil ring
Dimensions (B ×T) 1.50 ×1.95 mm (0.06 ×0.08 in)
End gap (installed) 0.20–0.70 mm (0.0079–0.0276 in)
Ring side clearance 0.040–0.160 mm (0.0016–0.0063 in)
Crankshaft
Width A 47.95–48.00 mm (1.888–1.890 in)
H
D
T
B
B
T
B
T

ENGINE SPECIFICATIONS
Runout limit C 0.030 mm (0.0012 in)
Big end side clearance D 0.110–0.410 mm (0.0043–0.0161 in)
Big end radial clearance E 0.004–0.014 mm (0.0002–0.0006 in)
Balancer
Balancer drive method Gear
Clutch
Clutch type Wet, multiple-disc
Clutch release method Inner push, cam push
Clutch lever free play 10.0–15.0 mm (0.39–0.59 in)
Friction plate 1 thickness 2.90–3.10 mm (0.114–0.122 in)
Wear limit 2.80 mm (0.1102 in)
Plate quantity 1 pc
Friction plate 3 thickness 2.90–3.10 mm (0.114–0.122 in)
Wear limit 2.80 mm (0.1102 in)
Plate quantity 3 pcs
Friction plate 2 thickness 2.90–3.10 mm (0.114–0.122 in)
Wear limit 2.80 mm (0.1102 in)
Plate quantity 1 pc
Clutch plate thickness 1.45–1.75 mm (0.057–0.069 in)
Plate quantity 4 pcs
Warpage limit 0.20 mm (0.0079 in)
Clutch spring free length 38.71 mm (1.52 in)
Minimum length 36.77 mm (1.45 in)
Spring quantity 4 pcs
Long clutch push rod bending limit 0.500 mm (0.0197 in)
Transmission
Transmission type
Primary reduction system
Primary reduction ratio
Secondary reduction system
Secondary reduction ratio
Operation
Constant mesh 6-speed
Helical gear
73/24 (3.042)
Gear ratio
1st 34/12 (2.833)
2nd 30/16 (1.875)
3rd 30/22 (1.364)
4th 24/21 (1.143)
5th 22/23 (0.957)
6th 21/25 (0.840)
Main axle runout limit 0.08 mm (0.0032 in)
D
A
E
CC

TIGHTENING TORQUES
EAS20320
TIGHTENING TORQUES
EAS20330
GENERAL TIGHTENING TORQUE
SPECIFICATIONS
This chart specifies tightening torques for stan-
dard fasteners with a standard ISO thread pitch.
Tightening torque specifications for special com-
ponents or assemblies are provided for each
chapter of this manual. To avoid warpage, tight-
en multi-fastener assemblies in a crisscross pat-
tern and progressive stages until the specified
tightening torque is reached. Unless otherwise
specified, tightening torque specifications re-
quireclean, drythreads. Components shouldbe
at room temperature.
A. Distance between flats
B. Outside thread diameter
A (nut) B (bolt) General tightening
torques
Nm m·kgf ft·lbf
10 mm 6 mm 6 0.6 4.3
12 mm 8 mm 15 1.5 11
14 mm 10 mm 30 3.0 22
17 mm 12 mm 55 5.5 40
19 mm 14 mm 85 8.5 61
22 mm 16 mm 130 13.0 94

TIGHTENING TORQUES
Generator cover tightening sequence:
Clutch cover tightening sequence:
Crankcase tightening sequence:
1,6 7
8
9
5
4
3,11 2,10
8
1,7
3,13 2,12
6
9
5
11
10
4
A
1,7
11
12
3,14
4
5
6
8
9
10
16
15
B
2,13
A. Left crankcase
B. Right crankcase

LUBRICATION SYSTEM CHART AND DIAGRAMS
EAS20390
LUBRICATION SYSTEM CHART AND DIAGRAMS
EAS20400
ENGINE OIL LUBRICATION CHART
1
6
5
2
4
3

LUBRICATION SYSTEM CHART AND DIAGRAMS
EAS20410
LUBRICATION DIAGRAMS
A
1
4
5
6
7
2
3