Page 48 of 88
PERIODIC MAINTENANCE AND ADJUSTMENT
7-3
7
√
5 *Cylinder Check cylinder for score marks or wear.
Clean.
√
Replace. √
NO. ITEM ROUTINE
After
break-in Every
race Every
third race Every
fifth race As
required
6 *Clutch Check clutch housing, friction plates, clutch plates
and clutch springs for wear or damage.
Adjust. √
√
Replace. √
7 *Transmission Change the transmission oil.
√
Check transmission for damage. √
Replace bearings. √
8 *Shift forks, guide bars,
shift cam
Replace if necessary. Check all parts for wear and damage.
√
9 *Rotor nut
(flywheel
magneto) Tighten.
√√√
10 *Kickstarter system Check idle gear for damage.
√
Replace if necessary.
11 *Exhaust system Check exhaust pipe and muffler for carbon deposits.
√
√
Clean. √
√
√
√
√
12
*Crankshaft Check crankshaft for carbon deposits and damage.
Clean.
U1SN81E0.book Page 3 Tuesday, June 12, 2012 3:17 PM
Page 62 of 88

PERIODIC MAINTENANCE AND ADJUSTMENT
7-17
7
WARNING
EWA14390
●
Have a Yamaha dealer replace
excessively worn tires. Operat-
ing the motorcycle with exces-
sively worn tires decreases
riding stability and can lead to
loss of control.
●
The replacement of all wheel-
and brake-related parts, includ-
ing the tires, should be left to a
Yamaha dealer, who has the
necessary professional knowl-
edge and experience.
●
It is not recommended to patch
a punctured tube. If unavoid-
able, however, patch the tube
very carefully and replace it as
soon as possible with a high-
quality product.
EAU48321
Spoke wheels
WARNING
EWA10610
The wheels on this model are not de-
signed for use with tubeless tires.
Do not attempt to use tubeless tires
on this model.To maximize the performance, durabil-
ity, and safe operation of your motorcy-
cle, note the following points regarding
the specified wheels.●
The wheel rims should be checked
for cracks, bends, warpage or oth-
er damage and the spokes for
looseness or damage before each
ride. If any damage is found, have
a Yamaha dealer replace the
wheel. Do not attempt even the
smallest repair to the wheel. A de-
formed or cracked wheel must be
replaced.
●
The wheel should be balanced
whenever either the tire or wheel
has been changed or replaced. An
unbalanced wheel can result in
poor performance, adverse han-
dling characteristics, and a short-
ened tire life.
Front tire:Size:
YZ85 70/100-17 40M
YZ85D 70/100-17 40M
YZ85LW 70/100-19 42M
YZ85LWD 70/100-19 42M
Manufacturer/model:
DUNLOP/D756F
Rear tire: Size:
YZ85 90/100-14 49M
YZ85D 90/100-14 49M
YZ85LW 90/100-16 52M
YZ85LWD 90/100-16 52M
Manufacturer/model: DUNLOP/D756
U1SN81E0.book Page 17 Tuesday, June 12, 2012 3:17 PM
Page 67 of 88

PERIODIC MAINTENANCE AND ADJUSTMENT
7-22
7
EAU51720
Changing the brake fluid Have a Yamaha dealer change the
brake fluid at the intervals specified in
the periodic maintenance and lubrica-
tion chart. In addition, have the oil seals
of the master cylinders and calipers as
well as the brake hoses replaced at the
intervals listed below or whenever they
are damaged or leaking.●
Oil seals: Replace every two
years.
●
Brake hoses: Replace every four
years.
EAU22760
Drive chain slack The drive chain slack should be
checked before each ride and adjusted
if necessary.
EAU41411
To check the drive chain slack1. Install the removable sidestand and place the motorcycle on it.TIPWhen checking and adjusting the drive
chain slack, there should be no weight
on the motorcycle.2. Shift the transmission into the neu-tral position.
3. Measure the drive chain slack as shown. 4. If the drive chain slack is incorrect,
adjust it as follows.
EAU41483
To adjust the drive chain slack
Consult a Yamaha dealer before ad-
justing the drive chain slack.1. Loosen the axle nut and the lock- nut on each side of the swingarm.
2. To tighten the drive chain, turn the drive chain slack adjusting bolt on
each side of the swingarm in direc-
tion (a). To loosen the drive chain,
turn the adjusting bolt on each side
of the swingarm in direction (b),
and then push the rear wheel for-
ward. NOTICE: Improper drive
chain slack will overload the en-
Drive chain slack: 35.0–45.0 mm (1.38–1.77 in)
1. Drive chain slack
U1SN81E0.book Page 22 Tuesday, June 12, 2012 3:17 PM
Page 83 of 88

SPECIFICATIONS
9-1
9
Dimensions:Overall length:YZ85 1818 mm (71.6 in)
YZ85D 1818 mm (71.6 in)
YZ85LW 1903 mm (74.9 in)
YZ85LWD 1903 mm (74.9 in)
Overall width:
758 mm (29.8 in)
Overall height: YZ85 1161 mm (45.7 in)
YZ85D 1161 mm (45.7 in)
YZ85LW 1205 mm (47.4 in)
YZ85LWD 1205 mm (47.4 in)
Seat height: YZ85 864 mm (34.0 in)
YZ85D 864 mm (34.0 in)
YZ85LW 904 mm (35.6 in)
YZ85LWD 904 mm (35.6 in)
Wheelbase:
YZ85 1255 mm (49.4 in)
YZ85D 1255 mm (49.4 in)
YZ85LW 1286 mm (50.6 in)
YZ85LWD 1286 mm (50.6 in)
Ground clearance: YZ85 351 mm (13.82 in)
YZ85D 351 mm (13.82 in)
YZ85LW 393 mm (15.47 in)
YZ85LWD 393 mm (15.47 in)Weight:Curb weight:
YZ85 71 kg (157 lb)
YZ85D 71 kg (157 lb)
YZ85LW 73 kg (161 lb)
YZ85LWD 73 kg (161 lb)
Engine:Engine type:Liquid cooled 2-stroke
Cylinder arrangement:
Single cylinder
Displacement: 84 cm³
Bore × stroke:
47.5 × 47.8 mm (1.87 × 1.88 in)
Compression ratio:
8.20 : 1
Starting system: Kickstarter
Lubrication system: PremixEngine oil:Type:YAMALUBE 2RTransmission oil:Type:
YAMALUBE 4 (10W-40) or SAE 10W-40
Oil change quantity: 0.50 L (0.53 US qt, 0.44 Imp.qt)Cooling system:Radiator capacity (including all routes):
0.54 L (0.57 US qt, 0.48 Imp.qt)Air filter:Air filter element:Wet elementFuel:Recommended fuel:Premium unleaded gasoline only
Fuel tank capacity: 5.0 L (1.32 US gal, 1.10 Imp.gal)
Carburetor:Type × quantity:
PWK28 x 1Spark plug(s):Manufacturer/model: NGK/BR10EG
Spark plug gap: 0.5–0.6 mm (0.020–0.024 in)Clutch:Clutch type:Wet, multiple-discTransmission:Primary reduction ratio:
3.611 (65/18)
Final drive: Chain
Secondary reduction ratio: YZ85 3.428 (48/14)
YZ85D 3.428 (48/14)
YZ85LW 3.714 (52/14)
YZ85LWD 3.714 (52/14)
Transmission type:
Constant mesh 6-speed
Operation: Left foot operation
Gear ratio: 1st:2.454 (27/11)
2nd: 1.882 (32/17)
3rd:
1.529 (26/17)
4th: 1.294 (22/17)
U1SN81E0.book Page 1 Tuesday, June 12, 2012 3:17 PM