Yamaha YBR 125
10 hp, 125 cc, 287 lbs2005 - 2016
Yamaha WR450F
50 hp, 449 cc, 273 lbs2012 - 2015
EngineYamaha YBR 125Yamaha WR450F
Displacement125 cc449 cc
Max power10 hp (@7 800 RPM)50 hp (@8 500 RPM)
Max torque6 lb ft (@6 000 RPM)36 lb ft (@7 500 RPM)
Redline10 000 RPM11 500 RPM
Idling speed1 250 RPM1 900 RPM
ManagementFuel InjectionFuel Injection
LayoutSOHC SingleDOHC Single
Compression10.00:112.30:1
Oil capacity1.14 quart0.95 quart
Oil type10W30, 10W4010W40
Spark plug typeNGK CR6HSANGK CR8E
CoolingAirLiquid
Valves25
Bore54.0 mm95.0 mm
Stroke54.0 mm63.4 mm
Throttle bore42.0 mm
Weight to power28.66 lbs/hp5.47 lbs/hp
Power to weight87 hp/2500lbs457 hp/2500lbs
Battery typeYTX7L-BS, 12V 6Ah12V 6Ah, YTZ7S (F)
GearboxYamaha YBR 125Yamaha WR450F
TypeSequentialSequential
ClutchWetWet
DriveChainChain
Chain typeDAIDO 520VM2 114 links
Gears count55
Primary ratio3.42.652
Final drive3.0713.846
1. gear2.643 (26 mph)2.417 (37 mph)
2. gear1.778 (39 mph)1.733 (52 mph)
3. gear1.316 (53 mph)1.313 (68 mph)
4. gear1.045 (66 mph)1.05 (84 mph)
5. gear0.875 (79 mph)0.84 (106 mph)
ChasisYamaha YBR 125Yamaha WR450F
Frame typeDiamond steelBilateral beam aluminum
Front susp.Telescopic fork, 110mm48mm USD, 11.81 in travel
Rear susp.Swingarm, 4.13 in travelSwingarm monoshock, 11.57 in travel