heating YAMAHA YFM50R 2006 Owners Manual

6-19
EBU02092
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. During
the first 20 hours, the various parts in the engine
wear and polish themselves to the correct oper-
ating clearances.
During this period, prolonged full throttle opera-
tion or any condition which might result in exces-
sive engine heating must be avoided. However,
momentary (2-3 seconds maximum) 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 engine
can rid itself of the temporary build up of heat.
5YF-9-62 6 2/23/05 6:54 PM Page 18

8-33
cC
Never operate the engine with the air filter
element removed. This will allow unfiltered
air to enter the engine, causing rapid engine
wear and possible engine damage.
Additionally, operation without the filter ele-
ment will affect carburetor jetting with sub-
sequent poor performance and possible
engine overheating.
5YF-9-62 8 2/23/05 6:56 PM Page 8-33