KTM 85 SX 2011 User Manual (English)

Questions and Answers:

A
Andrew JordanAug 19, 2025
Why does my KTM 85 SX 2011 Motorcycle engine have not enough power?
- B
  Brian JacksonAug 20, 2025
  If your KTM Motorcycle engine lacks power, several factors could be responsible. The glass fiber yarn in the silencer might be charred, the air filter could be obstructed, the fuel supply may be partly interrupted, or there could be a loss of compression due to a loose spark plug. Damage to the exhaust system or insufficient preignition could also be the cause. To address this, replace the silencer filling, clean or replace the air filter, blow through the fuel pipe and clean the carburetor, tighten the spark plug, check the exhaust system for damage, and check and adjust the ignition.
J
James OconnorAug 22, 2025
What to do if KTM Motorcycle engine is overheating?
- V
  Vincent BerryAug 22, 2025
  If your KTM Motorcycle engine is overheating, it could be due to insufficient liquid in the cooling system, clogged radiator fins, frothing in the cooling system, pinched water hoses, incorrect ignition timing because of loose stator screws or an incorrect compression ratio. To resolve this, top up the coolant and bleed the cooling system, checking for leaks. Clean the radiator fins with a water jet, renew the coolant using a branded anti-freeze/anti-corrosive, replace any incorrectly routed hoses, readjust the ignition timing and secure the screws, and measure and adjust the compression ratio.
S
Stephanie JenkinsAug 25, 2025
Why is my KTM 85 SX 2011 Motorcycle engine spluttering into the carburetor?
- E
  ejohnsonAug 26, 2025
  If your KTM Motorcycle engine is spluttering into the carburetor, it could be due to a lack of fuel, a spark plug with an incorrect heat value causing ignition by incandescence, or the engine taking in air uncontrollably. To fix this, clean the fuel pipes, examine the tank aeration, and clean it. Also, fit the correct spark plug and check the intake flange and carburetor to ensure they are firmly secured.
N
Nicholas EspinozaAug 27, 2025
What causes a KTM 85 SX 2011 engine to not rev up and run in a four stroke cycle?
- L
  ljohnsonAug 28, 2025
  If your KTM Motorcycle engine revs aren't up and it's running in a four-stroke cycle, the carburetor may be overflowing due to a level that's adjusted too high, a dirty or enlarged float needle seating, or loose carburetor jets. Clean the carburetor, and if necessary, replace the float needle and adjust the level. Also, tighten the jets.
E
Elizabeth SanchezAug 30, 2025
Why KTM 85 SX 2011 engine without idle running?
- M
  Mr. Matthew StewartAug 30, 2025
  If your KTM Motorcycle engine is not running smoothly at idle, it may be due to an improperly adjusted idle screw, damage to the ignition system, or general wear. Readjust the idle running or replace the idle adjusting screw. Also, examine the ignition system and consider overhauling the engine.
L
Lawrence SmithSep 2, 2025
What causes high rpm misfiring in a KTM Motorcycle?
- S
  Sharon JohnsonSep 2, 2025
  If your KTM Motorcycle engine is misfiring at high RPM, it could be due to an incorrect heat range spark plug or a low-quality spark plug, or a loose, corroded, or non-conductive ignition socket connector. Refer to the technical data section for the correct spark plug and check and seal the ignition socket connector with silicon.
J
Jason RivasSep 4, 2025
What to do if KTM 85 SX 2011 engine has not enough power because of reed valves?
- J
  Jaime RodriguezSep 5, 2025
  If your KTM Motorcycle engine lacks power and has reed paddles that are tensionless or damaged, or if the surface of the reed valve housing is damaged, you should replace the reed paddles or the reed valve housing. Also, consider overhauling the engine due to wear.
S
Sheryl WilliamsSep 8, 2025
Why is my KTM 85 SX 2011 emitting white smoke (steam)?
- S
  Sarah HaynesSep 8, 2025
  If white smoke (steam) is emitting from your KTM Motorcycle, it indicates a leak in the cylinder head or O-ring of the cylinder head gasket. You should check the cylinder head and replace the O-ring.
A
Angela CookSep 12, 2025
Why is excessive oil escaping from the transmission breather tube on my KTM 85 SX 2011?
- K
  kjohnsonSep 12, 2025
  If excessive oil is escaping from the transmission breather tube of your KTM Motorcycle, it is likely due to an excessive quantity of oil in the transmission. Correct the transmission oil level to resolve this issue.
J
Joe ConleySep 13, 2025
How to fix water in transmission oil of KTM Motorcycle?
- S
  saragarnerSep 13, 2025
  If there is water in the transmission oil of your KTM Motorcycle, it is likely due to a defect in the shaft seal ring of the water pump. Replace the shaft seal ring of the water pump to fix this issue.

KTM 85 SX 2011 Specifications

General

Engine Type	Single-cylinder, 2-stroke
Displacement	84.9 cc
Transmission	6-speed
Cooling	Liquid-cooled
Rear Suspension	WP Monoshock
Front Brake	Disc brake
Rear Brake	Disc brake
Starter	Kick starter
Lubrication	Premix
Fuel System	Carburetor
Front Suspension	Inverted fork, 43 mm
Front Tire	70/100-17
Clutch	Wet multi-disc
Frame	Steel
Rear Tire	90/100-14