Yamaha RD250(D) Betriebsanleitung Seite 64

Engine break-in
There is never a more important period, in the
life of your m o t o r c y c l e , than the period
between zero and 1,000 k m . F o r this reason
we ask that y o u carefully read the f o l l o w i n g
material. Because the engine is brand new,
y o u must not put an excessive load on it for
the first several hours of running. Düring the
first 1,000 k m the various parts in the engine
wear and polish themselves to the correct
operating clearances. Düring this period pro-
longed f ü l l throttle Operation, or any condi-
tion which might result in excessive heat of
cylinder, must be avoided. However,
momentary f ü l l throttle Operation, under
load (2 ~ 3 seconds m a x i m u m ) , does not
harm the engine. Each f ü l l throttle accelera-
tion sequence should be f o l l o w e d with a
substantial rest period for the engine by cruis-
ing at lower rpm's so the engine can rid itself
of the temporary build up of heat.
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