engine oil YAMAHA YZ85 2002 Owner's Guide

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TUNSETTING
Change of the heat range of spark plugs
Judging from the discoloration of spark plugs,
if they are found improper, it can be corrected
by the following two methods; changing carbu-
retor settings and changing the heat range of
spark plug.
lIn principle, it is advisable to first use spark
plugs of standard heat range, and judging
from the discoloration of spark plugs, adjust
carburetor settings.
lIf the calibration No. of the main jet must be
changed by ±30, it is advisable to change the
heat range of spark plugs and newly select
the proper main jet.
NOTE:
lWhen checking the discoloration of spark
plugs, be sure to stop the engine immedi-
ately after a run and check.
lAvoid racing.
lWhen changing the heat range of spark
plugs, never attempt to change it more than
±1 rank.
lWhen using spark plugs other than standard,
make sure of the difference in heat range
and find the equivalent to the standard.
lNote that even if the discoloration seems
proper, it may slightly vary with the spark
plug maker and oil in use.Standard spark plug BR10EG/NGK
5PA70110