2005 YAMAHA YZ85 gas type

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GEN
INFO
FUEL AND ENGINE MIXING OIL
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.
NOTE:
If knocking or pinging occurs, use a different
brand of gasoline or higher octane grade.
CAUTION:
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 premix prior to filling with the new
type.
Recommended fuel:
Premium unleaded gasoline
only with a research octane
number of 95 or higher.
Fuel tank capacity:
5 L (1.10 Imp gal, 1.32 US gal)
Mixing oil
Recommended oil:
Yamalube “2-R”
(Yamalube racing 2-cycle oil)
Mixing ratio: 30 : 1
If unavailable, use an equivalent
type of oil.
5PA10540

GEN
INFOMELANGE CARBURANT ET HUILE MOTEUR
KRAFTSTOFF UND BEIZUMISCHENDES MOTORÖL
MELANGE CARBURANT ET
HUILE MOTEUR
Mélanger le carburant et l’huile dans les propor-
tions spécifiées ci-dessous. Toujours utiliser de
l’essence fraîche, de marque connue, et effectuer le
mélange huile/essence le jour de la compétition. Ne
pas utiliser de mélange datant de plus de quelques
heures.
N.B.:
En cas de cognement ou de cliquetis, utiliser une
autre marque d’essence ou une essence d’un indice
d’octane supérieur.
ATTENTION:
Ne jamais utiliser deux types d’huile dans le
même mélange ; l’huile pourrait se figer. Avant
de changer de type d’huile, bien vidanger le
réservoir de carburant et la cuve à niveau cons-
tant du carburateur.
Carburant recommandé:
Supercarburant sans plomb avec
indice d’octane de recherche égal
ou supérieur à 95.
Capacité du réservoir de carburant:
5 L (1,10 Imp gal, 1,32 US gal)
Huile pour mélange
Huile recommandée:
Yamalube “2-R”
(huile 2 temps pour compétition
Yamalube)
Rapport de mélange: 30 : 1
En cas de non-disponibilité, utiliser
un autre type d’huile.
KRAFTSTOFF UND
BEIZUMISCHENDES MOTORÖL
Mischen Sie Öl und Benzin in dem unten
angegebenen Verhältnis. Verwenden Sie aus-
schließlich frisches Markenbenzin und
mischen Sie Öl und Benzin erst am Tag des
Rennens. Verwenden Sie keine vorgefertigte
Mischung, die älter ist als ein paar Stunden.
HINWEIS:
Wenn Klopfen oder Klingeln auftritt, verwen-
den Sie Benzin mit einer höheren Oktanzahl.
ACHTUNG:
Mischen Sie niemals zwei verschiedene
Ölsorten im gleichen Behälter; Dies kann
zum Verklumpen des Öls führen. Wenn Sie
die Ölsorte wechseln möchten, entleeren
Sie das alte Gemisch erst vollständig aus
dem Tank und dem Vergaser-Schwimmer-
gehäuse, bevor Sie das neue Gemisch ein-
füllen.
Empfohlener Kraftstoff:
Bleifreies Superbenzin mit einer
Research-Oktanzahl (ROZ) von
mindestens 95.
Fassungsvermögen des Kraft-
stofftanks:
5 L (1,10 Imp gal, 1,32 US gal)
Mischöl
Empfohlenes Öl:
Yamalube “2-R”
(Yamalube Racing 2-Takt-Öl)
Mischungsverhältnis: 30 : 1
Wenn nicht erhältlich, ein gleich-
wertiges Öl verwenden.
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SPEC
2 - 1
GENERAL SPECIFICATIONS
EC200000
SPECIFICATIONS
EC211000
GENERAL SPECIFICATIONS
Model name: YZ85 YZ85LW
YZ85T (USA, CDN,
AUS, NZ)
YZ85 (EUROPE, ZA)YZ85LW (EUROPE)
YZ85LWT (AUS, NZ)
Model code number: YZ85 YZ85LW
5PAA
(USA, CDN, EUROPE,
ZA)
5PAB
(AUS, NZ)5SHA
(EUROPE)
5SHB
(AUS, NZ)
Dimensions: YZ85 YZ85LW
Overall length 1,821 mm (71.7 in) 1,903 mm (74.9 in)
(USA, ZA)
1,818 mm (71.6 in)
(EUROPE, CDN, AUS,
NZ)
Overall width 758 mm (28.9 in)←
Overall height 1,161 mm (45.7 in) 1,205 mm (47.4 in)
Seat height 864 mm (34.0 in) 904 mm (35.6 in)
Wheelbase 1,258 mm (49.5 in) 1,286 mm (50.6 in)
(USA, ZA)
1,255 mm (49.4 in)
(EUROPE, CDN, AUS,
NZ)
Minimum ground clearance 351 mm (13.8 in) 393 mm (15.5 in)
Dry weight: YZ85 YZ85LW
Without oil and fuel 66 kg (145.5 lb) 69 kg (152.1 lb)
Engine:
Engine type Liquid cooled 2-stroke, gasoline
Cylinder arrangement Single cylinder, forward inclined
Displacement 84.7 cm
3 (2.98 Imp oz, 2.86 US oz)
Bore × stroke 47.5 × 47.8 mm (1.870 × 1.882 in)
Compression ratio 8.2 : 1
Starting system Kickstarter
Lubrication system: Premix (30 : 1) (Yamalube 2-R)
Oil type or grade (2-cycle):
Transmission oil Yamalube 4 (10W-30) or SAE 10W-30 type SE
motor oil
Periodic oil change 0.50 L (0.44 Imp qt, 0.52 US qt)
Total amount 0.55 L (0.48 Imp qt, 0.58 US qt)
Coolant capacity (including all routes): 0.54 L (0.48 Imp qt, 0.57 US qt)
Air filter: Wet type element
2

SPEC
2 - 2
GENERAL SPECIFICATIONS
Fuel:
Type Premium unleaded gasoline only with a
research octane number of 95 or higher.
Tank capacity 5.0 L (1.10 Imp gal, 1.32 US gal)
Carburetor:
Type/manufacturer PWK28/KEIHIN
Spark plug:
Type/manufacturer BR10EG/NGK (resistance type)
Gap 0.5 ~ 0.6 mm (0.020 ~ 0.024 in)
Clutch type: Wet, multiple-disc
Transmission: YZ85 YZ85LW
Primary reduction system Gear←
Primary reduction ratio 65/18 (3.611)←
Secondary reduction system Chain drive←
Secondary reduction ratio 47/14 (3.357) 52/14 (3.714)
(USA, ZA)
48/14 (3.429)
(EUROPE, CDN, AUS,
NZ)
Transmission type Constant mesh,
6-speed←
Operation Left foot operation←
Gear ratio: 1st 27/11 (2.454)←
2nd 32/17 (1.882)←
3rd 26/17 (1.529)←
4th 22/17 (1.294)←
5th 26/23 (1.130)←
6th 25/25 (1.000)←
Chassis: YZ85 YZ85LW
Frame type Semi double cradle←
Caster angle 26.3°26.9°
Trail 88 mm (3.46 in) 105.5 mm (4.15 in)
Tire: YZ85 YZ85LW
Type With tube←
Size (front) 70/100-17 40M 70/100-19 42M
Size (rear) 90/100-14 49M 90/100-16 52M
Tire pressure (front and rear) 100 kPa
(1.0 kgf/cm
2, 15 psi)←
Brake:
Front brake type Single disc brake
Operation Right hand operation
Rear brake type Single disc brake
Operation Right foot operation

2

SPEC
2 - 3
GENERAL SPECIFICATIONS
Suspension:
Front suspension Telescopic fork
Rear suspension Swingarm (link type monocross suspension)
Shock absorber:
Front shock absorber Coil spring/air, oil damper
Rear shock absorber Coil spring/gas, oil damper
Wheel travel: YZ85 YZ85LW
Front wheel travel 275 mm (10.8 in)←
Rear wheel travel 282 mm (11.1 in) 287 mm (11.3 in)
Electrical:
Ignition system CDI magneto

SPEC
2 - 8
MAINTENANCE SPECIFICATIONS
CHASSIS
YZ85
Item Standard Limit
Steering system:
Steering bearing type Taper roller bearing ----
Front suspension:
Front fork travel 275 mm (10.8 in) ----
Fork spring free length 430 mm (16.9 in) 425 mm (16.7 in)
Spring rate, STD K = 2.84 N/mm
(0.29 kg/mm, 16.2 lb/in)----
Optional spring Yes ----
Oil capacity318 cm
3
(11.2 Imp oz, 10.8 US oz) ----
Oil level 90 mm (3.54 in) ----

(From top of outer tube with inner
tube and damper rod fully com-
pressed without spring.)80 ~ 120 mm (3.15 ~ 4.72 in) ----
Oil grade Suspension oil “01”----
Inner tube outer diameter 36 mm (1.42 in) ----
Front fork top end 24 mm (0.94 in) ----
Rear suspension: USA, CDN,
AUS, NZ, ZAEUROPE
Shock absorber travel 102 mm (4.02 in)←----
Spring free length 220 mm (8.66 in)←----
Fitting length 215 mm (8.46 in) 212 mm (8.35 in) ----
202.5 ~ 218.5 mm
(7.97 ~ 8.60 in)←----
Spring rate, STD K = 49.0 N/mm
(5.00 kg/mm,
280.0 lb/in)K = 45.0 N/mm
(4.60 kg/mm,
257.6 lb/in)----
Optional spring Yes←----
Enclosed gas pressure 1,000 kPa
(10 kg/cm
2,
142 psi)←----
Swingarm:
Swingarm free play limit
End ---- 1.0 mm (0.04 in)

SPEC
2 - 10
MAINTENANCE SPECIFICATIONS
YZ85LW
Item Standard Limit
Steering system:
Steering bearing type Taper roller bearing ----
Front suspension:
Front fork travel 275 mm (10.8 in) ----
Fork spring free length 430 mm (16.9 in) 425 mm (16.7 in)
Spring rate, STD K = 2.94 N/mm
(0.30 kg/mm, 16.8 lb/in)----
Optional spring Yes ----
Oil capacity318 cm
3
(11.2 Imp oz, 10.8 US oz) ----
Oil level 90 mm (3.54 in) ----

(From top of outer tube with inner
tube and damper rod fully com-
pressed without spring.)80 ~ 120 mm (3.15 ~ 4.72 in) ----
Oil grade Suspension oil “01”----
Inner tube outer diameter 36 mm (1.42 in) ----
Front fork top end Zero mm (Zero in) ----
Rear suspension: AUS, NZ EUROPE
Shock absorber travel 102 mm (4.02 in)←----
Spring free length 220 mm (8.66 in)←----
Fitting length 207 mm (8.15 in) 212 mm (8.35 in) ----
202.5 ~ 218.5 mm
(7.97 ~ 8.60 in)←----
Spring rate, STD K = 51.0 N/mm
(5.20 kg/mm,
291.2 lb/in)K = 47.0 N/mm
(4.80 kg/mm,
268.8 lb/in)----
Optional spring Yes←----
Enclosed gas pressure 1,000 kPa
(10 kg/cm
2,
142 psi)←----
Swingarm:
Swingarm free play limit
End ---- 1.0 mm (0.04 in)

5 - 59
CHAS
HANDLING NOTE
WARNING
This rear shock absorber is provided with a
separate type tank filled with high-pressure
nitrogen gas. To prevent the danger of
explosion, read and understand the follow-
ing information before handling the shock
absorber.
The manufacturer can not be held respon-
sible for property damage or personal
injury that may result from improper han-
dling.
1. Never tamper or attempt to disassem-
ble the cylinder or the tank.
2. Never throw the rear shock absorber
into an open flame or other high heat.
The rear shock absorber may explode
as a result of nitrogen gas expansion
and/or damage to the hose.
3. Be careful not to damage any part of
the gas tank. A damaged gas tank will
impair the damping performance or
cause a malfunction.
4. Take care not to scratch the contact
surface of the piston rod with the cylin-
der; or oil could leak out.
5. Never attempt to remove the plug at
the bottom of the nitrogen gas tank. It
is very dangerous to remove the plug.
6. When scrapping the rear shock
absorber, follow the instructions on
disposal.
NOTES ON DISPOSAL (YAMAHA DEALERS
ONLY)
Before disposing the rear shock absorber, be
sure to extract the nitrogen gas from valve 1.
Wear eye protection to prevent eye damage
from escaping gas and/or metal chips.
WARNING
To dispose of a damaged or worn-out rear
shock absorber, take the unit to your
Yamaha dealer for this disposal procedure.
5PA51880
REAR SHOCK ABSORBER