compression ratio YAMAHA YZ85 2019 Owners Manual

Periodic maintenance an d a djustment
7-31
7
EAU25872
Trou bleshootin g
Although Yamaha motorcycles receive
a thorough inspection before shipment
from the factory, trouble may occur
during operation. Any problem in the
fuel, compression, or ignition systems,
for example, can cause poor starting
and loss of power.
The following troubleshooting charts
represent quick and easy procedures
for checking these vital systems your-
self. However, should your motorcycle
require any repair, take it to a Yamaha
dealer, whose skilled technicians have
the necessary tools, experience, and
know-how to service the motorcycle
properly.
Use only genuine Yamaha replace-
ment parts. Imitation parts may look
like Yamaha parts, but they are often
inferior, have a shorter service life and
can lead to expensive repair bills.
WARNING
EWA15142
When checkin g the fuel system, do
not smoke, an d make sure there are
no open flames or sparks in the ar-
ea, inclu din g pilot lig hts from water
heaters or furnaces. Gasoline or
g asoline vapors can i gnite or ex-
plod e, causin g severe injury or prop-
erty damag e.
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Specifications
9-1
9
Dimensions:
Overall length:1820 mm (71.7 in) (YZ85, YZ85K)
1895 mm (74.6 in) (YZ85LW, YZ85LWK)
Overall width: 760 mm (29.9 in)
Overall height:
1145 mm (45.1 in) (YZ85, YZ85K)
1175 mm (46.3 in) (YZ85LW, YZ85LWK)
Seat height:
840 mm (33.1 in) (YZ85, YZ85K)
870 mm (34.3 in) (YZ85LW, YZ85LWK)
Wheelbase:
1255 mm (49.4 in) (YZ85, YZ85K)
1285 mm (50.6 in) (YZ85LW, YZ85LWK)
Ground clearance: 330 mm (12.99 in) (YZ85, YZ85K)
360 mm (14.17 in) (YZ85LW, YZ85LWK)
Wei ght:
Curb weight:
73 kg (161 lb) (YZ85, YZ85K)
75 kg (165 lb) (YZ85LW, YZ85LWK)
Engine:
Combustion cycle:
2-stroke
Cooling system: Liquid cooled
Number of cylinders:
Single cylinder
Displacement: 85 cm³
Bore × stroke:
47.5 × 47.8 mm (1.87 × 1.88 in)
Compression ratio:
8.2–9.6 : 1
Starting system: Kickstarter
Lubrication system: Premix lubrication
Engine oil:
Engine oil:
YAMALUBE 2R
Recommended brand: YAMALUBE
Transmission oil:
Type:Motor oil SAE 10W-30 type SE or higher or
Gear oil SAE 85W GL-3
Quantity: 0.50 L (0.53 US qt, 0.44 Imp.qt)
Coolant quantity:
Radiator (including all routes): 0.55 L (0.58 US qt, 0.48 Imp.qt)
Air filter:
Air filter element:Wet element
Fuel:
Recommended fuel:
Premium unleaded gasoline (Gasohol [E10]
acceptable)
Fuel tank capacity:
5.0 L (1.3 US gal, 1.1 Imp.gal)
Car buretor:
Type × quantity:
PWK28 × 1
Spark plu g(s):
Manufacturer/model:
NGK/BR10EG
Spark plug gap: 0.5–0.6 mm (0.020–0.024 in)
Clutch:
Clutch type:
Wet, multiple-disc
Drivetrain:
Primary reduction ratio:3.611 (65/18)
Final drive:
Chain
Secondary reduction ratio: 3.286 (46/14) (YZ85, YZ85K)
3.643 (51/14) (YZ85LW, YZ85LWK)
Transmission type: Constant mesh 6-speed
Gear ratio: 1st:2.455 (27/11)
2nd: 1.882 (32/17)
3rd:
1.529 (26/17)
4th: 1.294 (22/17)
5th: 1.130 (26/23)
6th:
1.000 (25/25)
Chassis:
Frame type: Semi double cradle
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