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Yamaha · European two-stroke single (DKW, Jawa, CZ, MZ, Puch, Bultaco, Montesa, Ossa)

Why (49 cc)

Library entry covers 2006-2010

25 factory 39 guideline

Published source

Yamaha YH50 Why 2006 Owner's Manual 5XS-F8199-E0 (UK, English), periodic maintenance and lubrication chart pp.6-2 to 6-4

Factory owner's handbook. Covers YH50 Why (49 cc); 2006 UK owner's manual 5XS-F8199-E0, English. Chart columns 1/6/12/18/24 x1000 km plus annual check (km only, no mile figures printed); from 30000 km repeat the intervals starting from 6000 km; annual checks every year unless a km-based maintenance is performed instead. Two-stroke with Autolube oil injection: no engine oil, oil filter or valve rows.

Open the source

64 items for a 2007 model, grouped by interval the way a factory chart is laid out.

How this bike is built (what the schedule is based on)

Engine cycle: Two-stroke
Engine lubrication: Two-stroke premix (oil in fuel)
Oil filtration: None (no filter)
Valve gear: None (two-stroke porting)
Ignition: Magneto (incl. magdyno, flywheel magneto)
Charging: Alternator / stator with rectifier
Battery: Wet cell (flooded lead-acid, needs topping up)
Fuel system: Single carburetor
Cooling: Air / oil cooled
Primary drive: Gear or chain inside engine, shares engine oil
Gearbox oil: Separate gearbox oil
Clutch control: Automatic or semi-automatic
Final drive: Leather or rubber V-belt (veteran)
Front suspension: Telescopic fork
Rear suspension: Swingarm, twin shocks
Front brake: Drum (or band / stirrup)
Rear brake: Drum (or band / belt rim)
Wheels: Spoked, tubed
Sidecar: No sidecar

Maintenance schedule

2007 Yamaha Why (49 cc)

On the road: every 100 mi

1 item

Check drive belt tension and belt fastener

Pre-ride / on the road

Guideline

Leather and early rubber belts stretch and slip when wet. Carry a spare fastener and a belt punch.

On the road: every 150 mi

1 item

Check two-stroke oil tank / carry premix oil

Pre-ride / on the road

Guideline

Running a two-stroke out of oil seizes it. Injection bikes: check the tank. Premix: carry oil and a measure.

On the road: every 300 mi

2 items

Check lights, horn, brake light switches

Pre-ride / on the road

Guideline
Check tire pressures

Pre-ride / on the road

Guideline

Every 500 mi

1 item

Dress / clean V-belt and pulley rims

Final drive

Guideline

Every 1,000 mi or 6 months

1 item

Adjust front drum brake

Brakes

Guideline

Every 2,000 mi or 12 months

1 item

Replace spark plugs (two-stroke)

Engine

Guideline

Every 3,000 mi or 12 months

8 items

Check throttle cable(s) free play and return

Fuel and air

Guideline
Clean fuel tap filter / sediment bowl

Fuel and air

Guideline
Check / set ignition timing

Ignition and electrics

Guideline
Clean and gap contact breaker points, oil cam felt

Ignition and electrics

Guideline
Adjust automatic / semi-automatic clutch

Primary and gearbox

Guideline
Inspect fork seals, stanchions and fork boots

Front end

Guideline
Check footrests, pegs, rear brake and gear lever pivots

Rear suspension and frame

Guideline
Check spoke tension and wheel true

Wheels and tires

Guideline

Every 3,000 mi or 2 years

1 item

Decarbonize exhaust ports, pipes and baffles

Engine

Guideline

Two-strokes coke up the exhaust port and muffler baffles; power falls off gradually.

Every 3,728 mi or 12 months

12 items

Chassis fasteners (make sure all nuts, bolts and screws are properly tightened)

Engine

Factory

Factory: Marked 6000-24000 km; annual check; dealer item (p.6-3)
Lights, signals and switches (check operation, adjust headlight beam)

Engine

Factory

Factory: Every column incl. 1000 km initial; annual check; dealer item (p.6-4)
Replace spark plugs

Engine

Factory

Manual: Spark plug (replace). Factory: Replace marked at 6000, 12000, 18000, 24000 km; not at 1000 km; annual check marked; no separate inspect row (p.6-2)
Carburetor (adjust engine idling speed)

Fuel and air

Factory

Factory: Every column incl. 1000 km initial; annual check; dealer item (p.6-3)
Replace fuel lines

Fuel and air

Factory

Manual: Fuel line (check fuel hoses and vacuum hose for cracks or damage). Factory: Marked 6000-24000 km; not at 1000 km; annual check; dealer item (p.6-2)
Battery (check electrolyte level and specific gravity, check breather hose routing)

Ignition and electrics

Factory

Factory: Marked 6000-24000 km; annual check; dealer item (p.6-2)
Grease and check center / side stand and springs

Rear suspension and frame

Factory

Manual: Centerstand (check operation, lubricate). Factory: Marked 6000-24000 km; annual check (p.6-3)
Adjust rear drum brake and rod / cable linkage

Brakes

Factory

Manual: Rear brake (check operation and adjust brake lever free play; replace brake shoes whenever worn to the limit). Factory: Every column incl. 1000 km initial; annual check; shoes replaced whenever worn to the limit; dealer item (p.6-2)
Check brake pads and discs

Brakes

Factory

Manual: Front brake (check operation, fluid level and vehicle for fluid leak; replace brake pads whenever worn to the limit). Factory: Hydraulic front brake. Check every column incl. 1000 km initial; annual check; pads replaced whenever worn to the limit; dealer item (p.6-2)
Front and rear brake switches (check operation)

Brakes

Factory

Factory: Every column incl. 1000 km initial; annual check; dealer item (p.6-3)
Inspect tire tread, sidewalls and date codes

Wheels and tires

Factory

Manual: Tires (check tread depth and for damage, replace if necessary, check and correct air pressure). Factory: Marked 6000-24000 km; annual check; dealer item (p.6-3)
Lubricate control cables and lever pivots

Controls and cables

Factory

Manual: Moving parts and cables (lubricate). Factory: Marked 6000-24000 km; annual check (p.6-4)

Every 3,728 mi

5 items

Check steering head bearing adjustment

Front end

Factory

Manual: Steering bearings (check bearing play and steering for roughness). Factory: Marked at 1000, 6000, 12000, 18000, 24000 km; no annual check; dealer item (p.6-3)
Front fork (check operation and for oil leakage)

Front end

Factory

Factory: Marked 6000-24000 km; no annual check; no fork oil change interval printed; dealer item (p.6-3)
Inspect rear shocks for leaks and damping

Rear suspension and frame

Factory

Manual: Shock absorber assembly (check operation and shock absorber for oil leakage). Factory: Marked 6000-24000 km; no annual check; dealer item (p.6-3)
Check wheel bearings for play

Wheels and tires

Factory

Manual: Wheel bearings (check bearing for looseness or damage). Factory: Marked 6000-24000 km; no annual check; dealer item (p.6-3)
Wheels (check runout and for damage)

Wheels and tires

Factory

Factory: Marked 6000-24000 km; no annual check; dealer item (p.6-2)

Every 4,000 mi or 12 months

2 items

Inspect, clean and gap spark plugs

Engine

Guideline
Lubricate brake cam spindles, check linings and drums

Brakes

Guideline

Every 6,000 mi or 12 months

4 items

Clean carburetor float bowl(s), check float level and jets

Fuel and air

Guideline

Ethanol fuel varnishes old carbs quickly in storage.
Check charging voltage and regulator / cut-out

Ignition and electrics

Guideline
Check swingarm bushes for play

Rear suspension and frame

Guideline
Lubricate speedometer / tachometer cables, check drive

Controls and cables

Guideline

A dry speedo cable whips the needle and eventually kills the instrument.

Every 6,000 mi or 2 years

2 items

Lubricate and check automatic advance unit

Ignition and electrics

Guideline
Magneto: clean slip ring and pickup brush, check HT lead

Ignition and electrics

Guideline

Every 6,214 mi

1 item

Replace drive belt (wear or damage based)

Final drive

Factory

Manual: V-belt (replace). Factory: Every 10000 km, printed as text; no belt inspection row; dealer item (p.6-3)

Every 7,456 mi or 12 months

1 item

Autolube pump (check operation, bleed if necessary)

Engine

Factory

Factory: Two-stroke oil injection pump. Marked at 1000, 12000 and 24000 km (not 6000 or 18000 km); annual check; dealer item (p.6-3)

Every 7,456 mi

3 items

Clean / inspect air filter

Fuel and air

Factory

Manual: Air filter element (clean). Factory: Clean marked at 6000 and 18000 km only (alternating with replace); with the repeat-from-6000 km rule this is every 12000 km offset by 6000 km; no annual check. NOTE: more frequent service in unusually wet or dusty areas (pp.6-2, 6-4)
Replace air filter element

Fuel and air

Factory

Manual: Air filter element (replace). Factory: Replace marked at 12000 and 24000 km; no annual check; more frequent service in unusually wet or dusty areas (pp.6-2, 6-4)
Change final drive (rear drive) oil

Final drive

Factory

Manual: Final transmission oil (change). Factory: Change marked at 1000 km initial, 12000 and 24000 km; check vehicle for oil leakage marked at 1000, 6000 and 18000 km; no annual check (p.6-3)

Every 10,000 mi or 2 years

2 items

Compression test (or leak-down)

Engine

Guideline
Change gearbox oil

Primary and gearbox

Guideline

Every 12,000 mi or 2 years

1 item

Grease swingarm pivot

Rear suspension and frame

Guideline

Every 12,000 mi or 3 years

1 item

Replace points and condenser

Ignition and electrics

Guideline

Every 14,913 mi

1 item

Repack / replace steering head bearings

Front end

Factory

Manual: Steering bearings (lubricate with lithium-soap-based grease). Factory: Every 24000 km, printed as text; dealer item (p.6-3)

Every 15,000 mi or 3 years

1 item

Change fork oil

Front end

Guideline

Some early telescopic forks are grease filled or use very small oil quantities. Check your manual.

Every 15,000 mi

1 item

Replace brake linings / skim drums (wear based)

Brakes

Guideline

Every 20,000 mi or 4 years

1 item

Repack / replace wheel bearings

Wheels and tires

Guideline

Cup-and-cone and taper roller hubs need periodic repacking and adjustment.

Every 25,000 mi or 6 years

1 item

Replace swingarm bushes / bearings

Rear suspension and frame

Guideline

Every 25,000 mi or 10 years

1 item

Magneto overhaul / re-magnetize, replace capacitor

Ignition and electrics

Guideline

Weak spark when hot is the classic symptom. Old capacitors fail with age, not miles.

Every 30,000 mi or 6 years

1 item

Rebuild forks: seals, bushes, springs

Front end

Guideline

Every 6 months

1 item

Clean battery terminals, check charge and strap

Ignition and electrics

Guideline

Every 2 years

3 items

Inspect wiring, bullet connectors and ground points

Ignition and electrics

Guideline
Inspect frame, welds and lugs for cracks

Rear suspension and frame

Guideline
Replace brake fluid

Brakes

Factory

Manual: Brake fluid (change). Factory: From the hydraulic brake service NOTE under the chart: every two years change the brake fluid; regularly check and correct fluid level; not a chart row (p.6-4)

Every 4 years

1 item

Inspect brake hoses; replace old rubber

Brakes

Factory

Manual: Brake hose (replace). Factory: Every 4 years (also NOTE: replace if cracked or damaged); check for cracks or damage marked 6000-24000 km and annually; dealer item (pp.6-2, 6-4)

Every 6 years

2 items

Replace inner tubes and rim tape with tires

Wheels and tires

Guideline
Replace tires on age (regardless of tread)

Wheels and tires

Guideline

Guideline lines: Intervals here are general guidelines for the machine's era and layout, compiled for this app. They are not factory manual figures. Check your workshop manual, and edit any interval in the bike's Schedule tab.