Yamaha YP125R, Service Manual

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ENGINE SPECIFICATIONS (YP125R)
2-8
Secondary reduction ratio 44/13 (3.385)
Operation Centrifugal automatic type
Gear ratio 2.645–0.824 :1
Decompression device
Device type Auto decomp
Air filter
Air filter element Oil-coated paper element
Fuel pump
Pump type Electrical
Output pressure 250.0 kPa (2.50 kgf/cm², 36.3 psi)
Fuel injector
Model/quantity 1P51/1
Throttle body
Type/quantity EFI 1B91/1
ID mark 1B91 00
Throttle position sensor
Input voltage (at idle) 5 V
Output voltage (at idle) 0.40–0.90 V
Fuel injection sensor
Crankshaft position sensor resistance 248–372
Ω
at 20 °C (68 °F)
Intake air pressure sensor output voltage 3.57–3.71 V
Intake air temperature sensor resistance 2.21–2.69 k
Ω
at 20 °C (68 °F)
Coolant temperature sensor resistance 2.32–2.59 k
Ω
at 20 °C (68 °F)
310–326
Ω
at 80 °C (176 °F)
Idling condition
Engine idling speed 1600–1800 r/min
CO% (muffler tailpipe) 0.5%
Intake vacuum 67.0–73.0 kPa (503–548 mmHg, 19.8–21.6
inHg)
Water temperature 80.0–90.0 °C (176.00–194.00 °F)
Oil temperature 75.0–85.0 °C (167.00–185.00 °F)
Throttle cable free play 3.0–5.0 mm (0.12–0.20 in)