2005 YAMAHA TTR90 Owners Manual

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YAMAHA TTR90 2005  Owners Manual GEN
INFO
MEMO

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YAMAHA TTR90 2005  Owners Manual SPEC
2 - 1
EC200000
SPECIFICATIONS
EC211000
GENERAL SPECIFICATIONS
Model name: TT-R90T (CDN, AUS, NZ)
TT-R90 (Europe, ZA)
TT-R90ET (USA, CDN, AUS, NZ)
TT-R90E (Europe, ZA)
Model code number: TT-R90:
5

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YAMAHA TTR90 2005  Owners Manual SPEC
2 - 2 Oil type or grade:
Engine oil
 (For USA and CDN)
At –10 ˚C (10 ˚F) or higher Å
Yamalube 4 (10W-30) or SAE 10W-30 type
SE/SF motor oil 
At 5 ˚C (40 ˚F) or higher ı
Yamalube 4 (20W-40

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YAMAHA TTR90 2005  Owners Manual SPEC
2 - 3 Transmission:
Primary reduction system Spur gear
Primary reduction ratio 67/18 (3.722)
Secondary reduction system Chain drive
Secondary reduction ratio 35/14 (2.500)
Transmission type Const

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YAMAHA TTR90 2005  Owners Manual SPEC
2 - 4
MAINTENANCE SPECIFICATIONS
ENGINE
Item Standard Limit
Cylinder head:
Warp limit ---- 0.03 mm 
(0.0012 in)
Cylinder:
Bore size 47.000 ~ 47.005 mm
(1.8504 ~ 1.8506 in)47.05 mm
(1.8524 in)
Out

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YAMAHA TTR90 2005  Owners Manual SPEC
2 - 5 Cam chain:
Cam chain type/No. of links 92RH2005-84M/84 ----
Cam chain adjustment method Automatic ----
Rocker arm/rocker arm shaft:
Shaft outside diameter 9.981 ~ 9.991 mm
(0.3930 ~ 0.3933

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YAMAHA TTR90 2005  Owners Manual SPEC
2 - 6 Stem runout limit ---- 0.02 mm
(0.0008 in)
Valve seat width IN 0.9 ~ 1.1 mm 
(0.0354 ~ 0.0433 in)1.6 mm
(0.0630 in)
EX 0.9 ~ 1.1 mm 
(0.0354 ~ 0.0433 in)1.6 mm
(0.0630 in)
Valve spring:
Fre

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YAMAHA TTR90 2005  Owners Manual SPEC
2 - 7 Piston:
Piston to cylinder clearance 0.025 ~ 0.045 mm
(0.0010 ~ 0.0018 in)0.15 mm
(0.0059 in)
Piston size “D”46.960 ~ 46.975 mm
(1.8488 ~ 1.8494 in)----
Piston over size (2nd) 47.5 mm (