Engine Break-In - Yamaha YFM 90 2021 Owner's Manual

1. Bring the ATV to a complete stop.
2. Apply the rear brake lever.
3. Shift from neutral to reverse by moving the
drive select lever along the shift guide.
TIP
When in reverse, the reverse indicator light should
come on. If the indicator light does not come on,
have a Yamaha dealer check the electrical circuit.
1. Drive select lever
2. F (Forward)
3. N (Neutral)
4. R (Reverse)
4. Check behind for people or obstacles, and
then release the rear brake lever.
2 F
3 N
4 R
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5. Open the throttle lever gradually and continue
to watch to the rear while backing.
EBU20684

Engine break-in

There is never a more important period in the life
of your engine than the first 320 km (200 mi) or 20
hours of operation. For this reason, you should fol-
low the engine break-in instructions carefully.
Since the engine is brand new, do not put an ex-
cessive load on it for the first 320 km (200 mi) or
20 hours. During this period the various parts in
the engine wear and polish themselves to the cor-
rect operating clearances. Avoid prolonged full-
throttle operation or any condition that might re-
sult in engine overheating.
0–160 km (0–100 mi) or 0–10 hours
Avoid prolonged operation above 1/2 throttle.
Vary the speed of the ATV regularly. Do not oper-
ate it at one set throttle position.
160–320 km (100–200 mi) or 10–20 hours
Avoid prolonged operation above 3/4 throttle. Rev
the engine freely, but do not use full throttle at any
time.
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