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EBU00209
Engine break-in
There is never a more important period in the
life of your machine than the period between
zero and 20 hours.
For this reason, we ask that you carefully read
the following material. Because the engine is
brand new, you must not put an excessive load
on it for the first several hours of running. Dur-
ing the first 20 hours, the various parts in the
engine wear and polish themselves to the cor-
rect operating clearances.
During this period, prolonged full throttle oper-
ation or any condition which might result in ex-
cessive engine heating must be avoided.
However, momentary (2 ~ 3 seconds maxi-
mum) full throttle operation under load does
not harm the engine.
Each full throttle acceleration sequence should
be followed with a substantial rest period for
the engine by cruising at lower r/min so the en-
gine can rid itself of the temporary build up of
heat.
If any abnormality is noticed during this peri-
od, consult a Yamaha dealer.
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CAUTION:Never operate the engine with the air filter el-
ement removed. This will allow unfiltered air
to enter, causing rapid engine wear and possi-
ble engine damage. Additionally, operation
without the filter element will affect carbure-
tor jetting with subsequent poor performanceand possible engine overheating.
EBU00296
Carburetor adjustment
The carburetor is a vital part of the engine and
requires very sophisticated adjustment. Most
adjusting should be left to a Yamaha dealer
who has the professional knowledge and expe-
rience to do so. However, the idling speed may
be performed by the owner as a part of the
usual maintenance routine.CAUTION:The carburetor was set at the Yamaha factory
after many tests. If the settings are disturbed
by someone without sufficient technical
knowledge, poor engine performance anddamage may result.
