Yamaha PZ50FXW, Owner'S Manual

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ESU04540
Adjusting the high-altitude settings
Operating at high altitude reduces the performance of a
gasoline engine about 3% for every 305 m (1,000 ft) of
elevation. This is because there is less air as altitude
increases. Less air means less oxygen available for com-
bustion.
Your snowmobile utilizes an electronic fuel injection sys-
tem that delivers the optimal air/fuel ratio required by the
engine. Therefore, the fuel injection system does not
need to be adjusted, even for operation at high altitude.
Remember:
Less air at higher altitude means there is less horse-
power available, even with the optimal air/fuel ratio.
Expect acceleration and top speed to be reduced at
higher altitudes.
To overcome operating with less power at high altitudes,
your snowmobile may also require different settings for
the drive chain gears and V-belt clutch to avoid poor per-
formance and rapid wear. If you plan to operate your
snowmobile at an altitude different from the area where
you bought it, be sure to consult a Yamaha dealer. The
dealer can tell you if there are any changes necessary
for the altitude where you plan to ride.
CAUTION:
@
The drive chain gears and V-belt clutch should be
adjusted when operating above a high altitude of
900 m (3,000 ft). Consult a Yamaha dealer.
@
ESU00348
Adjusting the valve clearance
The valve clearance changes with use, resulting in
improper air-fuel mixture and/or engine noise. To prevent
this from occurring, the valve clearance must be adjusted
by a Yamaha dealer at the intervals specified in the peri-
odic maintenance chart.
E_8gk.book Page 12 Friday, June 16, 2006 9:53 AM