What causes Cam chain tensioner wear causing rattle on the Kawasaki Z650S?

Cold start noise, metallic rattling from engine top end Estimated fix cost: $150-$300

What causes Carb jets clogged from ethanol fuel damage on the Kawasaki Z650S?

Rough idle, hesitation, hard starting after storage Estimated fix cost: $80-$200

Oil weeping around fork tubes above dust seals Estimated fix cost: $100-$250

Battery drain, voltage above 15V or below 13V running Estimated fix cost: $80-$180

Known issues to inspect before buying a used Kawasaki Z650S. What to check and how much repairs cost.

MODERATE

Cold start noise, metallic rattling from engine top end

Fix cost: $150-$300

MODERATE

Rough idle, hesitation, hard starting after storage

Fix cost: $80-$200

MINOR

Oil weeping around fork tubes above dust seals

Fix cost: $100-$250

SERIOUS

Battery drain, voltage above 15V or below 13V running

Fix cost: $80-$180

☐Cold start and listen for top-end rattle

☐Check fork tubes for oil residue staining

☐Test charging voltage with multimeter

☐Inspect carbs for varnish and fuel leaks

Solid older bike, maintenance history matters most