Yamaha YZF-R125 Service Manual: Cooling system diagrams

Lubrication diagrams

Clutch push lever Main axle Drive axle Crankshaft Oil filter Oil pump assembly Oil strainer To cylinder head Camshaft Crankshaft Main axle Drive axle ...

Cable routing

Front brake light switch lead Right handlebar switch lead Throttle cable Main switch Clutch cable Clutch switch lead Left handlebar switch lead Sub-wire harness Horn Speed sen ...

Other materials:

Engine oil and oil filter element
The engine oil level should be checked before each ride. In addition, the oil must be changed and the oil filter element replaced at the intervals specified in the periodic maintenance and lubrication chart. To check the engine oil level Place the vehicle on a level surface and hol ...

Checking the cylinder head
1. Eliminate: Combustion chamber carbon deposits (with a rounded scraper) NOTE: Do not use a sharp instrument to avoid damaging or scratching: Spark plug bore threads Valve seats 2. Check: Cylinder head Damage/scratches   Replace. Cylinder head water jacket Min ...

Starting failures
Engine 1. Cylinder and cylinder head - Loose spark plug - Loose cylinder head or cylinder - Damaged cylinder head gasket - Damaged cylinder gasket - Worn or damaged cylinder - Incorrect valve clearance - Improperly sealed valve - Incorrect valve-to-valve-seat contact - Incorrect valve timi ...