Rato R160 User manual

GASOLINE ENGINE
R100-R440 HORIZONTAL SHAFT
SERVICE MANUAL
CHONGQING RATO POWER
MANUFACTURING CORPORATION

This manual contains information about how to perform routine maintenance and how to do
troubleshooting.
Keep this manual handy, so you can refer to it at any time.
This service manual describes correct methods for maintaining this equipment. If any
personal casualty or equipment damage is caused due to disregard of our rules, our company
does not assume any responsibility.
NOTICE:
Copyright is reserved, and no part of this publication may be reproduced without RATO
Company’s written permission.

SAFETY MESSAGES
Your safety and the safety of others are very important. We have provided important safety
messages in this manual and on the generator. Please read these messages carefully.
A safety message alerts you to potential hazards that could injure you or others. Each safety
message is preceded by a safety alert symbol and one of three words: DANGER,
WARNING, or CAUTION. These messages mean:
You WILL be KILLED or SERIOUSLY INJURED if you don’t follow
instructions.
You CAN be KILLED or SERIOUSLY INJURED if you don’t follow
instructions.
You CAN be INJURED if you don’t follow instructions.
Your generator or other property could be damaged if you don’t
follow instructions.

CONTENTS
1. INTRODUCTION ···················································································· 1!
1-1 PARTS DESCRIPTION ······································································ 1!
1-2 SPECIFICATION·············································································· 2!
1-3 SERVICE LIMIT ·············································································· 5!
2. DIMENSIONS AND TORQUE ·································································· 19!
2-1 ENGINE DIMENSIONS···································································· 19!
2-1-1 R100 ························································································· 19!
2-1-2 R160/R180/R200/R210/R225 ······················································ 19!
2-1-3 R270/R280/R300 ····································································· 20!
2-1-4 R390/R420/R440 ····································································· 21!
2-2 TORQUE VALUES ········································································· 22!
2-2-1 torque values ·········································································· 22!
2-3 STANDARD Torque valueS ······························································· 24!
3. MAINTENANCE ··················································································· 25!
3-1. Maintenance schedule ······································································ 25!
3-2 engine oil ······················································································ 26!
3-3 Air cleaner····················································································· 27!
3-4 Cleaning of the fuel filter ··································································· 27!
3-5 spark plug cleaning and ····································································· 28!
adjusting···························································································· 28!
3-6 valve clearance adjustment ································································· 28!
3-7 governor ······················································································· 29!
4. DISASSEMBLING AND SERVICING ························································· 30!
4-1 Troubleshooting ·············································································· 30!
4-1-1 Hard starting ·········································································· 30!
4-1-2 Engine lacks power····································································· 2!
4-1-3 Speed is unstable ······································································· 3!
4-1-4 Motor is unable to start ································································ 3!
4-1-5 Exhaust gas color is abnormal ························································ 4!

4-1-6 Unable to ignite ········································································· 4!
4-1-7 Oil alert system malfunction ·························································· 5!
4-1-8 GASOLINE ENGINE IS OVERERHEATED ····································· 5!
4-2 Preparation of servicing ······································································· 6!
4-2-1 Safety precautions ······································································ 6!
4-3 DisASSEMBLING chart ···································································· 46!
4-4 Engine ························································································· 47!
4-4-1 Recoil starter ·········································································· 48!
4-4-2 Flywheel ··············································································· 50!
4-4-3 Air cleaner············································································· 52!
4-4-4 Carburetor ············································································· 54!
4-4-5 Cylinder head /valve ································································· 57!
4-4-6 Crankshaft/piston ····································································· 63!
4-4-7 Starting control box ·································································· 71!

1
1. INTRODUCTION
1-1 PARTS DESCRIPTION
Throttle grip
Fuel tank
Recoil starter
Muffler
Spark plug
Choke lever
Air cleaner
Fuel tank cover
Start handle
Drain plug
Oil dipstick

2
1-2 SPECIFICATION
Model
items
R100
R160
L×W×H
310×290×320mm
390×320×345mm
Dry Weight
8.8 kg
15.5kg
Engine Type
4-stroke, OHV, single cylinder
Displacement
98 cm3
163cm3
Compression Ratio
8.5±0.3:1
Bore×Stroke
56×40 mm
68×45mm
Maximum Output Power
1.8／3600 rpm
3.4kW/3,600rpm
Maximum Torque
4.7N·m/2500rpm
9N·m/2,500rpm
Cooling System
Forced Air-cooled
Ignition System
Transistorized Magneto Ignition(TCI)
Spark Plug
BPR6ES(NGK)，NHSP LD F7RTC，F7TC
Lubrication System
Forced Splash
PTO Shaft Rotation
Counterclockwise
Model
items
R180
R200
L×W×H
390×320×345mm
390×320×345mm
Dry Weight
16kg
16kg
Engine Type
4-stroke, OHV, single cylinder
Displacement
179cm3
196cm3
Compression Ratio
8.5:1
Bore×Stroke
65×54mm
68×54mm
Maximum Output Power
3.5kW/3,600rpm
4.0kW/3,600rpm
Maximum Torque
9N·m/2,500rpm
11N·m/2,500rpm
Cooling System
Forced Air-cooled
Ignition System
Transistorized Magneto Ignition(TCI)
Spark Plug
BPR6ES(NGK)，NHSP LD F7RTC，F7TC
Lubrication System
Forced Splash
PTO Shaft Rotation
Counterclockwise
Model
items
R210
R225
L×W×H
390×320×345mm
390×320×345mm

3
Dry Weight
16.5 kg
16.5kg
Engine Type
4-stroke, OHV, single cylinder
Displacement
212 cm3
223cm3
Compression Ratio
8.5±0.3
Bore×Stroke
70×55 mm
70×58mm
Maximum Output Power
4.2／3600 rpm
4.4kW/3,600rpm
Maximum Torque
12N·m/2500rpm
13N·m/2,500rpm
Cooling System
Forced Air-cooled
Ignition System
Transistorized Magneto Ignition(TCI)
Spark Plug
BPR6ES(NGK)，NHSP LD F7RTC，F7TC
Lubrication System
Forced Splash
PTO Shaft Rotation
Counterclockwise
Model
items
R270
R280
L×W×H
420×395×430mm
420×395×430mm
Dry Weight
26kg
26kg
Engine Type
4-stroke, OHV, single cylinder
Displacement
270cm3
277cm3
Compression Ratio
8.2：1
Bore×Stroke
77×58mm
78×58mm
Maximum Output Power
5.8kW/3,600rpm
6kW/3,600rpm
Maximum Torque
16.8N·m /2,500rpm
18N·m /2,500rpm
Cooling System
Forced Air-cooled
Ignition System
Transistorized Magneto Ignition(TCI)
Spark Plug
BPR6ES(NGK)，NHSP LD F7RTC，F7TC
Lubrication System
Forced Splash
PTO Shaft Rotation
Counterclockwise
Model
items
R300
R390
L×W×H
420×395×430mm
465×415×440mm
Dry Weight
26kg
27.5kg
Engine Type
4-stroke, OHV, single cylinder
Displacement
301cm3
389cm3

4
Compression Ratio
8.2：1
8：1
Bore×Stroke
80×60mm
88×64mm
Maximum Output Power
6kW/3,600rpm
7.6kW/3,600rpm
Maximum Torque
18N·m /2,500rpm
23N·m /2,500rpm
Cooling System
Forced Air-cooled
Ignition System
Transistorized Magneto Ignition(TCI)
Spark Plug
BPR6ES(NGK)，NHSP LD F7RTC，F7TC
Lubrication System
Forced Splash
PTO Shaft Rotation
Counterclockwise
Model
items
R420
R440
L×W×H
465×415×440mm
465×415×440mm
Dry Weight
28kg
28.5kg
Engine Type
4-stroke, OHV, single cylinder
Displacement
420cm3
438cm3
Compression Ratio
8.5：1
8.5：1
Bore×Stroke
90×66mm
92×66mm
Maximum Output Power
8.5kW/3,600rpm
9.8kW/3,600rpm
Maximum Torque
25N·m /2,500rpm
27N·m /2,500rpm
Cooling System
Forced Air-cooled
Ignition System
Transistorized Magneto Ignition(TCI)
Spark Plug
BPR6ES(NGK)，NHSP LD F7RTC，F7TC
Lubrication System
Forced Splash
PTO Shaft Rotation
Counterclockwise

5
1-3 SERVICE LIMIT
1-3-1 R100
Parts
Item
Standard Value
Service Limit
Gasoline
Engine
Maximum Speed (No load)
Cylinder Compression
3850rpm
0.9Mpa（1400rpm）
--
Cylinder
Cylinder Bore I.D.
56-56.015mm
56.165
Cylinder
Head
Warpage
--
0.1
Piston
Skirt O.D.
Piston-to-Cylinder Clearance
Piston Pin Bore I.D.
Piston Pin O.D
Piston Pin-to-Piston Pin Bore Clearance
55.975-55.985mm
0.015-0.04mm
14 .002-14.008mm
13.992-13.998mm
0.004-0.016mm
55.9
0.12
14.048
13.954
0.03
Piston Rings
Ring Side Clearance：Top /Second Ring
Oil Ring
Ring End Gap: Top /Second Ring
Oil Ring
Ring Width：Top /Second/Oil Ring
0.03-0.07mm
--
0.15-0.3mm
0.1-0.6mm
1.5mm
2.5mm
0.15
--
1
1
1.37
2.37
Connecting
Rod
Small End I.D
Big End I.D
Big End Oil Clearance
Small End Side Clearance
14.011-14.022mm
23.02-23.03mm
0.035-0.055mm
0.1-0.7mm
14.05
23.05
0.12
1.1
Crankshaft
Crankshaft Pin O.D
22.975-22.985mm
22.945
Valves
Valve Clearance
Stem O.D
Guide I.D
Stem-to-Guide Clearance
Seat Width
Spring Free Length
IN
EX
IN
EX
IN／EX
IN
EX
0.15±0.02mm
0.20±0.02mm
5.465-5.48mm
5.445-5.46mm
5.50-5.512mm
0.015-0.052mm
0.015-0.052mm
0.8mm
25.0mm
--
--
5.318
5.275
5.572
0.1
0.12
2.0
24
Camshaft
Cam Height IN
29.4mm
29.2

6
EX
Journal O.D
29.4mm
12.966-12.986mm
29.2
12.91
Crankcase
Cover
Camshaft Holder I.D.
13.0-13.018mm
13.048
1-3-2 R160/R200
Parts
Item
Standard Value
Service Limit
Gasoline
Engine
Maximum Speed (No Load)
Cylinder Compression
3750-3810rpm
≧1.17Mpa（1400rpm）
--
--
Cylinder
Cylinder Bore I.D.
68.0mm
68.165mm
Cylinder
Head
Warpage
--
0.10mm
Piston
Skirt O.D.
Piston-to-Cylinder Clearance
Piston Pin Bore I.D.
Piston Pin O.D.
Piston Pin-to-Piston Pin Bore Clearance
67.985mm
0.015-0.05mm
18 .002mm
18.0mm
0.002-0.014mm
67.845mm
0.12mm
18.048mm
17.954mm
0.06mm
Piston Rings
Ring Side Clearance：Top /Second Ring
Oil Ring
Ring End Gap: Top /Second Ring
Oil Ring
Ring Width：Top /Second/Oil Ring
0.015-0.045mm
--
0.2-0.4mm
0.15-0.35mm
1.5mm
2.5mm
0.15mm
--
1.0mm
1.0mm
1.37mm
2.37mm
Connecting
Rod
Small End I.D.
Big End I.D.
Big End Oil Clearance
Small End Side Clearance
18.002mm
30.02mm
0.040-0.063mm
0.1-0.7mm
18.07mm
30.066mm
0.12mm
1.1mm
Crankshaft
Crankshaft pin O.D
29.98mm
29.92mm
Valve
Valve Clearance
Stem O.D
Guide I.D
Stem-to-Guide Clearance
Seat Width
IN
EX
IN
EX
IN／EX
IN
EX
0.15±0.02mm
0.20±0.02mm
5.48mm
5.44mm
5.50mm
0.02-0.044mm
0.06-0.087mm
0.8mm
--
--
5.318mm
5.275mm
5.572mm
0.1mm
0.12mm
2.0mm

7
Spring Free Length
34.0mm
32.5mm
Camshaft
Cam Height IN
EX
Journal O.D
27.7mm
27.75mm
13.984mm
27.45mm
27.50mm
13.916mm
Crankcase
Cover
Camshaft Holder I.D.
14.0mm
14.048mm
Carburetor
Main Jet
Float Height
Pilot Screw Opening
0.85
13.7±1.5mm
2-1/8 circle
--
--
--
Spark Plug
Gap
0.7-0.8mm
--
Spark Plug
Cap
Resistance
7.5-12.5kΩ
--
Ignition Coil
Resistance
Air gap
Primary Coil
Secondary Coil
0.8-1.0Ω
5.9-7.1kΩ
0.4-0.6mm
--
--
--
1-3-3 R180
Parts
Item
Standard Value
Service Limit
Gasoline
Engine
Maximum Speed (No Load)
Cylinder Compression
3750-3810rpm
1.17Mpa（1400rpm）
--
--
Cylinder
Cylinder Bore I.D.
70.0mm
70.165mm
Cylinder
Head
Warpage
--
0.10mm
Piston
Skirt O.D.
Piston-to-Cylinder Clearance
Piston Pin Bore I.D.
Piston Pin O.D.
Piston Pin-to-Piston Pin Bore Clearance
69.985mm
0.015-0.05mm
18 .002mm
18.0mm
0.002-0.014mm
69.845mm
0.12mm
18.048mm
17.954mm
0.06mm
Piston Rings
Ring Side Clearance：Top /Second Ring
Oil Ring
Ring End Gap: Top /Second Ring
Oil Ring
Ring Width：Top /Second/Oil Ring
0.015-0.045mm
--
0.2-0.4mm
0.15-0.35mm
1.5mm
2.5mm
0.15mm
--
1.0mm
1.0mm
1.37mm
2.37mm
Connecting
Rod
Small End I.D.
Big End I.D.
18.011mm
30.02mm
18.07mm
30.066mm

8
Big End Oil Clearance
Small End Side Clearance
0.040-0.063mm
0.1-0.7mm
0.12mm
1.1mm
Crankshaft
Crankshaft pin O.D
29.98mm
29.92mm
Valve
Valve Clearance
Stem O.D
Guide I.D
Stem-to-Guide Clearance
Seat Width
Spring Free Length
IN
EX
IN
EX
IN／EX
IN
EX
0.15±0.02mm
0.20±0.02mm
5.48mm
5.44mm
5.50mm
0.02-0.044mm
0.06-0.087mm
0.8mm
34.0mm
--
--
5.318mm
5.275mm
5.572mm
0.1mm
0.12mm
2.0mm
32.5mm
Camshaft
Cam Height IN
EX
Journal O.D
27.7mm
27.75mm
14.184mm
27.45mm
27.50mm
14.166mm
Crankcase
Cover
Camshaft Holder I.D.
14.2mm
14.048mm
Carburetor
Main Jet
Float Height
Pilot Screw Opening
0.85
13.7±1.5mm
2-1/8 circle
--
--
--
Spark Plug
Gap
0.7-0.8mm
--
Spark Plug
Cap
Resistance
7.5-12.5kΩ
--
Ignition Coil
Resistance
Air gap
Primary Coil
Secondary Coil
0.8-1.0Ω
5.9-7.1kΩ
0.4-0.6mm
--
--
1-3-4 R210/R225
Parts
Item
Standard Value
Service Limit
Gasoline
Engine
Maximum Speed (No Load)
Cylinder Compression
3750-3810rpm
1.17Mpa（1400rpm）
--
Cylinder
Cylinder Bore I.D.
70.0mm
70.165mm
Cylinder
Head
Warpage
--
0.10mm
Piston
Skirt O.D.
Piston-to-Cylinder Clearance
69.985mm
0.015-0.05mm
69.845mm
0.12mm

9
Piston Pin Bore I.D.
Piston Pin O.D.
Piston Pin-to-Piston Pin Bore Clearance
18 .002mm
18.0mm
0.002-0.014mm
18.048mm
17.954mm
0.06mm
Piston Rings
Ring Side Clearance：Top /Second Ring
Oil Ring
Ring End Gap: Top /Second Ring
Oil Ring
Ring Width：Top /Second/Oil Ring
0.015-0.045mm
--
0.2-0.4mm
0.15-0.35mm
1.5mm
2.5mm
0.15mm
--
1.0mm
1.0mm
1.37mm
2.37mm
Connecting
Rod
Small End I.D.
Big End I.D.
Big End Oil Clearance
Small End Side Clearance
18.011mm
30.02mm
0.040-0.063mm
0.1-0.7mm
18.07mm
30.066mm
0.12mm
1.1mm
Crankshaft
Crankshaft pin O.D
29.98mm
29.92mm
Valve
Valve Clearance
Stem O.D
Guide I.D
Stem-to-Guide Clearance
Seat Width
Spring Free Length
IN
EX
IN
EX
IN／EX
IN
EX
0.15±0.02mm
0.20±0.02mm
5.48mm
5.44mm
5.50mm
0.02-0.044mm
0.06-0.087mm
0.8mm
34.0mm
--
--
5.318mm
5.275mm
5.572mm
0.1mm
0.12mm
2.0mm
32.5mm
Camshaft
Cam Height IN
EX
Journal O.D
27.7mm
27.75mm
13.984mm
27.45mm
27.50mm
13.916mm
Crankcase
Cover
Camshaft Holder I.D.
14.0mm
14.048mm
Carburetor
Main Jet
Float Height
Pilot Screw Opening
0.85
13.7±1.5mm
2-1/8 circle
--
--
--
Spark Plug
Gap
0.7-0.8mm
--
Spark Plug
Cap
Resistance
7.5-12.5kΩ
--
Ignition Coil
Resistance
Primary Coil
0.8-1.0Ω
--

10
Air gap
Secondary Coil
5.9-7.1kΩ
0.4-0.6mm
--
--
1-3-5 R270
Parts
Item
Standard
Service limit
Engine
Maximum speed (No load)
Cylinder compression
3150-3180rpm
≧1.37Mpa（1400rpm）
--
--
Cylinder
head
Sleeve I.D.
77-77.017mm
77.17mm
Cylinder
head
Warpage
--
0.10mm
Piston
Skirt O.D.
Piston-to-cylinder clearance
Piston pin bore I.D.
Piston pin O.D.
Piston pin-to-piston pin bore clearance
76.965-76.985mm
0.015-0.052mm
18 .002-18.008mm
17.994-18mm
0.002-0.014mm
76.85mm
0.12mm
18.042mm
17.95mm
0.08mm
Piston rings
Ring side clearance: first/ second
Oil
Ring end gap: first/second
Oil
Ring width:first/second
Oil
0.015-0.045mm
--
0.2-0.4mm
0.2-0.7mm
1.5mm
2.0mm
0.15mm
--
1.0mm
1.0mm
1.37mm
2.0mm
Connecting
rod
Small end I.D
Big end I.D
Big end oil clearance
Big end side clearance
18.005-18.02mm
33.025-33.039mm
0.040-0.066mm
0.1-0.7mm
18.07mm
30.07mm
0.12mm
1.0mm
Crankshaft
Crankshaft pin O.D
32.975-32.985mm
32.92mm
Valves
Valve clearance
Stem O.D.
Guide I.D.
Stem clearance
Seat width
Spring free length
IN
EX
IN
EX
IN/EX
IN
EX
0.15±0.02mm
0.20±0.02mm
6.575-6.59mm
6.535-6.55mm
6.6-6.612mm
0.01-0.037mm
0.05-0.077mm
1.1mm
--
--
6.44mm
6.4mm
6.66mm
0.11mm
0.13mm
2.0mm
37.5mm

11
1-3-6 R280
Parts
Item
Standard
Service limit
Engine
Maximum speed (No load)
Cylinder compression
3750-3850rpm
1.1Mpa（1400rpm）
--
--
Cylinder
head
Sleeve I.D.
78.0-78.015mm
78.17mm
Cylinder
head
Warpage
--
0.10mm
Piston
Skirt O.D.
Piston-to-cylinder clearance
Piston pin bore I.D.
Piston pin O.D.
Piston pin-to-piston pin bore clearance
77.96-76.98mm
0.015-0.055mm
18 .202-18.208mm
18.192-18.198mm
0.004-0.016mm
76.85mm
0.12mm
18.242mm
18.15mm
0.08mm
Piston rings
Ring side clearance: first/ second
Oil
Ring end gap: first/second
Oil
Ring width:first/second
Oil
0.02-0.06mm
--
0.20-0.40mm
0.2-0.7mm
3.4-3.6mm
2.75-3.15mm
0.15mm
--
1.0mm
1.0mm
1.37mm
2.0mm
Connecting
Small end I.D
18.211-18.222mm
18.27mm
39.0mm
camshaft
Cam height
Journal O.D
IN
EX
32.9-33.1mm
32.50-32.70mm
15.966-15.984mm
32.88mm
32.48mm
15.92mm
Crankcase
cover
Camshaft holder I.D
16.0mm
16.048mm
Carburetor
Main jet
Float height
Pilot screw opening
0.88
13.2mm
2-7/8 turns
--
--
--
Spark plug
Gap
0.7-0.8mm
--
Spark plug
cap
Resistance
7.5-12.5kΩ
--
Ignition coil
Resistance
Air gap
Primary coil
Secondary coil
0.6-0.9Ω
5.6-6.9kΩ
0.2-0.6mm
--
--
--

12
rod
Big end I.D
Big end oil clearance
Big end side clearance
33.225-33.239mm
0.013-0.03mm
0.25-0.65mm
33.27mm
0.12mm
1.0mm
Crankshaft
Crankshaft pin O.D
33.175-33.185mm
33.12mm
Valves
Valve clearance
Stem O.D.
Guide I.D.
Stem clearance
Seat width
Spring free length
IN
EX
IN
EX
IN/EX
IN
EX
0.10-0.15mm
0.15-0.20mm
6.575-6.59mm
6.535-6.55mm
6.6-6.615mm
0.01-0.04mm
0.05-0.08mm
0.8-1.0mm
38.5-39.5mm
--
--
6.44mm
6.4mm
6.66mm
0.10mm
0.12mm
2.0mm
37.5mm
camshaft
Cam height
Journal O.D
IN
EX
6.045mm
5.766mm
16.166-16.184mm
5.95mm
5.65mm
16.12mm
Crankcase
cover
Camshaft holder I.D
16.2-16.218mm
16.248mm
Carburetor
Main jet
Float height
Pilot screw opening
Φ2
1-3mm
2-7/8 circle
--
--
--
Spark plug
Gap
0.7-0.8mm
--
Spark plug
cap
Resistance
9.5-10.5kΩ
--
Ignition coil
Resistance
Air gap
Primary coil
Secondary coil
0.6-0.9Ω
5.6-6.9kΩ
0.3-0.5mm
--
--
--
1-3-7 R300
Parts
Item
Standard
Service limit
Engine
Maximum speed (No load)
Cylinder compression
3750-3850rpm
1.1Mpa（1400rpm）
--
--
Cylinder
head
Sleeve I.D.
80.0-80.015mm
80 .17mm
Cylinder
head
Warpage
--
0.10mm

13
Piston
Skirt O.D.
Piston-to-cylinder clearance
Piston pin bore I.D.
Piston pin O.D.
Piston pin-to-piston pin bore clearance
79.975-79.985mm
0.015-0.04mm
15 .002-15.008mm
14.992-14.998mm
0.004-0.016mm
79.85mm
0.12mm
15.242mm
14.95mm
0.08mm
Piston rings
Ring side clearance: first/ second
Oil
Ring end gap: first/second
Oil
Ring width:first/second
Oil
0.025-0.06mm
--
0.20-0.40mm
0.30-0.50mm
0.2-0.7mm
2.8-3.0mm
2.45-2.75mm
0.15mm
--
1.0mm
1.0mm
1.0mm
1.37mm
2.0mm
Connecting
rod
Small end I.D
Big end I.D
Big end oil clearance
Big end side clearance
15.011-15.022mm
33.025-33.039mm
0.013-0.03mm
0.25-0.65mm
15.27mm
33.07mm
0.12mm
1.0mm
Crankshaft
Crankshaft pin O.D
32.975-32.985mm
32.92mm
Valves
Valve clearance
Stem O.D.
Guide I.D.
Stem clearance
Seat width
Spring free length
IN
EX
IN
EX
IN/EX
IN
EX
0.10-0.15mm
0.15-0.20mm
5.468-5.48mm
5.43-5.445mm
5.485-5.5mm
0.005-0.032mm
0.04-0.07mm
0.8-1.0mm
38.5-39.5mm
--
--
5.34mm
5.3mm
5.56mm
0.10mm
0.12mm
2.0mm
37.5mm
camshaft
Cam height
Journal O.D
IN
EX
6.045mm
5.766mm
16.166-16.184mm
5.95mm
5.65mm
16.12mm
Crankcase
cover
Camshaft holder I.D
16.2-16.218mm
16.248mm
Carburetor
Main jet
Float height
Pilot screw opening
Φ2
1-3mm
2-7/8 circle
--
--
--
Spark plug
Gap
0.7-0.8mm
--

14
Spark plug
cap
Resistance
9.5-10.5kΩ
--
Ignition coil
Resistance
Air gap
Primary coil
Secondary coil
0.6-0.9Ω
5.6-6.9kΩ
0.3-0.5mm
--
--
--
1-3-8 R390
Parts
Item
Standard
Service limit
Engine
Maximum speed (No load)
Cylinder compression
3750-3810rpm
≧1.37Mpa（1400rpm）
--
--
Cylinder
head
Sleeve I.D
88-88.017mm
88.17mm
Cylinder
head
Warpage
--
0.10mm
Piston
Skirt O.D.
Piston-to-cylinder clearance
Piston pin bore I.D.
Piston pin O.D
Piston pin-to-piston pin bore clearance
87.965-87.985mm
0.015-0.052mm
20 .002-20.008mm
19.994-20mm
0.002-0.014mm
87.85mm
0.12mm
20.042mm
19.95mm
0.08mm
Piston rings
Ring side clearance: first/ second
Oil
Ring end gap: first/second
Oil
Ring width：first/second
Oil
0.015-0.045mm
--
0.2-0.4mm
0.2-0.7mm
1.5mm
2.0mm
0.15mm
--
1.0mm
1.0mm
1.37mm
2.0mm
Connecting
rod
Small end I.D
Big end I.D
Big end oil clearance
Big end side clearance
20.005-20.02mm
36.025-36.039mm
0.040-0.066mm
0.1-0.7mm
20.07mm
36.07mm
0.12mm
1.0mm
Crankshaft
Crankshaft pin O.D
35.975-35.985mm
35.92mm
Valves
Valve clearance
Stem O.D
Guide I.D
Stem clearance
IN
EX
IN
EX
IN/EX
IN
0.15±0.02mm
0.20±0.02mm
6.575-6.59mm
6.535-6.55mm
6.6-6.612mm
0.01-0.037mm
--
--
6.44mm
6.4mm
6.66mm
0.11mm