4-6 MACHINE TUNING
JUDGING AIR/FUEL MIXTURE
For proper carburetor tuning, it is necessary to
know how to judge the air/fuel mixture made in the
carburetor; whether too rich, too lean or properly
mixed. Given below are the symptoms observed
when the engine is not supplied with the proper
air/fuel mixture ratio from the carburetor. Check
each item as reference for judging the air/fuel mix-
ture condition.
When air/fuel mixture is too rich
1) The engine noise is dull and intermittent.
2) The engine condition becomes worse when the
starter is applied.
3) The engine condition becomes worse as it is
warmed up.
4) The engine condition improves when the air
cleaner is removed.
5) The spark plug is fouled with carbon (wet and
oily).
6) The exhaust gas produces heavy smoke.
When air/fuel mixture is too lean
1) The engine overheats.
2) The engine condition improves when the starter
is applied.
3) Acceleration is poor.
4) The spark plug is burned white.
5) The speed of the engine fluctuates and lack of
power is noticed.
6) Detonation and pinging are experienced.
TUNING PROCEDURE
The following indicates the correct tuning procedure
for this motorcycle. Understand the procedure by
first riding the motorcycle where it will be used and
adjust the engine to the best condition after judging
the air/fuel mixture.
Carburetor standard setting
Main jet:
#128
Jet needle: 24NAAH-3rd
Slow jet:
#50
Air screw: 2 turns out
INCLUDED PARTS AND OPTIONAL PARTS
Main jet
Slow jet
Jet Needle
NOTE:
SHADED : STANDARD
*
: INCLUDED PARTS
NONE
: OPTIONAL PARTS
Air/fuel
mixture
SIZE
P/NO
Lean
#115
09491-23027
#118
09491-23028
#120
09491-24030
* #122
09491-24031
#125
09491-25019
#128
09491-25020
* #130
09491-26017
#132
09491-26018
* #135
09491-27016
#138
09491-27017
#140
09491-28019
#142
09491-28020
Rich
#145
09491-29014
Air/fuel
mixture
SIZE
P/NO
Lean
#45
09492-45032
#48
09492-48013
#50
09492-50023
#52
09492-52011
#55
09492-55017
Rich
#58
09492-58001
Air/fuel
mixture
SIZE
P/NO
Lean
24NCDK
13383-03B90
24NAAK
13383-03B40
24NCDJ
13383-03B80
24NAAJ
13383-03B30
24NCDH
13383-03B70
24NAAH
13383-03B20
24NCDG
13383-03B60
24NAAG
13383-03B10
24NCDF
13383-03B50
Rich
24NAAF
13383-03B00
Summary of Contents for RM85
Page 1: ...Part No 99011 02B82 01A April 2006 EN TK RM85 L OWNER S SERVICE MANUAL ...
Page 10: ... MEMO ...
Page 42: ...3 TROUBLESHOOTING 3 1 CONTENTS TROUBLESHOOTING TROUBLESHOOTING 3 2 ENGINE 3 2 CHASSIS 3 5 ...
Page 47: ... MEMO ...
Page 85: ...7 2 CLUTCH CONSTRUCTION CLUTCH 70 N m 7 0 kgf m 50 5 lb ft ...
Page 93: ...8 2 KICK STARTER CONSTRUCTION KICK STARTER ...
Page 97: ... MEMO ...
Page 115: ... MEMO ...
Page 117: ...11 2 FUEL SYSTEM CONSTRUCTION FUEL SYSTEM ...
Page 121: ...11 6 FUEL SYSTEM REASSEMBLY Reverse the sequence of removal ...
Page 141: ... MEMO ...
Page 200: ...SERVICING INFORMATION 18 15 Radiator hose Throttle cable Clamp Clutch cable ...
Page 205: ... MEMO ...