Ktm Sm 990 Common Problems
Known issues to inspect before buying a used Ktm Sm 990. What to check and how much repairs cost.
Oil consumption and leaking from cylinder head
MODERATECheck oil level, look for residue around head gasket
Fix cost: $200-$600
Cam chain tensioner failure causing engine rattle
SERIOUSCold start rattle, listen for ticking at idle
Fix cost: $300-$800
Throttle body sync issues causing rough idle
MODERATEIdle quality, surging at low RPM, throttle response
Fix cost: $100-$300
Frame cracks near subframe mounting points
SERIOUSInspect welds around subframe, look for cracks visually
Fix cost: $500-$1500
Pre-Purchase Checklist
☐Check service history, valve clearances done
☐Cold start the bike, listen carefully
☐Inspect frame welds with flashlight
☐Test ride, check throttle smoothness throughout range
Decent if maintained, neglected examples get expensive fast