Yamaha YZ 2015 Series, Owner'S Service Manual

Page: 49 / 396

ENGINE SPECIFICATIONS
2-6
Crankshaft
Crank assembly width 55.95–56.00 mm (2.203–2.205 in)
Runout limit C 0.030 mm (0.0012 in)
Big end side clearance D 0.150–0.450 mm (0.0059–0.0177 in)
Balancer
Balancer drive method Gear
Clutch
Clutch type Wet, multiple-disc
Clutch release method Inner push, cam push
Clutch lever free play 7.0–12.0 mm (0.28–0.47 in)
Friction plate thickness 2.90–3.10 mm (0.114–0.122 in)
Wear limit 2.85 mm (0.112 in)
Plate quantity 9 pcs
Clutch plate thickness 1.10–1.30 mm (0.043–0.051 in)
Plate quantity 8 pcs
Warpage limit 0.10 mm (0.004 in)
Clutch spring free length 47.80 mm (1.88 in)
Limit 46.80 mm (1.84 in)
Spring quantity 5 pcs
Push rod bending limit 0.10 mm (0.004 in)
Transmission
Transmission type Constant mesh 6-speed
Primary reduction system Spur gear
Primary reduction ratio 3.353 (57/17)
Final drive Chain
Secondary reduction ratio 3.923 (51/13)
Operation Left foot operation
Gear ratio
1st 2.385 (31/13)
2nd 1.813 (29/16)
3rd 1.444 (26/18)
4th 1.143 (24/21)
5th 0.957 (22/23)
6th 0.815 (22/27)
Shifting mechanism
Shift mechanism type Shift drum and guide bar
Shift fork guide bar bending limit 0.050 mm (0.0020 in)
Shift fork thickness 4.85 mm (0.1909 in)
Decompression device
Device type Auto decomp
Air filter
Air filter element Wet element
Air filter oil grade Foam air-filter oil
C
C
D
A