Yamaha YZ250 2022, Owner'S Service Manual

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STARTING AND BREAK-IN
1-18
EAM20123
STARTING AND BREAK-IN
EAM30538
FUEL AND ENGINE MIXING OIL
Mix oil with the gas at the ratio specified below.
Always use fresh, name-brand gasoline, and
mix the oil and gas the day of the race. Do not
use premix that is more than a few hours old.
TIP
If knocking or pinging occurs, use a different
brand of gasoline or higher octane grade.
NOTICE
ECA22260
Never mix two types of oil in the same batch;
clotting of the oil could result. If you wish to
change oil types, be sure to drain the fuel
tank and the carburetor float bowl of old pre-
mix prior to filling with the new type.
EAM30196
STARTING A COLD ENGINE
1. Shift the transmission into neutral.
2. Turn the fuel cock to “ON” and full open the
starter knob (CHOKE).
3. With the throttle completely closed start the
engine by kicking the kickstarter forcefully
with firm stroke.
4. Run the engine at idle or slightly higher until it
warms up: this usually takes about one or two
minutes.
5. The engine is warmed up when it responds
normally to the throttle with the starter knob
(CHOKE) turned off.
WARNING
EWA19030
Since exhaust gas contains harmful ingredi-
ents, do not start or warm it up at an illventi-
lated place or a closed narrow place.
6. To stop the engine, push the engine stop
switch.
TIP
Continue pushing the engine stop switch till the
engine comes to a full stop.
EAM30197
STARTING A WARM ENGINE
Do not operate the starter knob (CHOKE). Open
the throttle slightly and start the engine by kick-
ing the kickstarter forcefully with firm stroke.
EAM30198
BREAK-IN PROCEDURES
A break-in is important so that rotating portion,
sliding surfaces, and mounted areas may fit one
another, and that the rider may become accus-
tomed to the machine.
NOTICE
ECA25811
Before running, do maintenance on the air
filter element.
1. Before starting the engine, fill the fuel tank
with a break-in oil-fuel mixture as follows.
2. Start and warm up the engine.
3. After warming up the engine, drive it for about
20 minutes at a throttle opening of 1/2 or less.
4. Make a pit stop, and check mounted areas for
looseness, oil leaks, or other problems.
5. Then, drive it for about 40 minutes at a throt-
tle opening of 3/4 or less.
6. Make a pit stop again, and thoroughly check
mounted areas for looseness, oil leaks, or
other problems. Thorough checks and ad-
justments are required in particular for stretch
of cables, free play of the brake, stretch of the
drive chain, looseness of the spoke, and so
Recommended fuel
Premium unleaded gasoline
(E10 acceptable)
Fuel tank capacity
7.0 L (1.8 US gal, 1.5 Imp.gal)
Engine oil
Lubrication system
Premix lubrication
Engine oil
YAMALUBE 2R
Premix ratio
30
Engine oil
YAMALUBE 2R
Premix ratio
15