Motocross · Four stroke

KTM 250 SX-F

KTM's 250 four stroke motocross bike. The one with the most top end in the class, electric start and a hydraulic clutch as standard. Sold in Australia from 2006 to 2026, 21 model years.

Add my 250 SX-F to the GarageShop parts for this bike

About the KTM 250 SX-F

The 250 SX F is the 250F for riders who like to rev. It makes the strongest top end power of the 250 four strokes, it is the lightest, and it has had electric start and a hydraulic clutch since long before the Japanese bikes. The current generation (2023 onwards) adds a quickshifter and traction control through the map switch.

It suits a fast junior stepping up, a lightweight clubman, or anyone who wants the most competitive 250F engine. It is less torquey and less forgiving than a YZ250F, so a newer rider will find the Yamaha easier. Against a Husqvarna FC 250 or GasGas MC 250F it is the same bike with different suspension and bodywork.

What changed by year

2013 to 2015
Electric start, hydraulic clutch, linkage rear end. Strong engine, dated chassis by today's standards, cheap now.
2016 to 2018
New generation: lighter engine and frame, air fork from 2017. A big step.
2019 to 2022
Revised frame and engine with more bottom end, updated air fork, map switch with traction and launch control. The most common used 250 SX F.
2023 onwards
All new frame, engine and bodywork, quickshifter, phone tuning. The current bike.

Servicing a 250 SX-F

A 250F that lives on the limiter wants oil every 5 to 8 hours, filter every second change. It takes about a litre with a filter and KTM specifies a JASO MA 10W 60 or 10W 50 full synthetic. Check the level with the sight glass after a warm up.

Air filter every ride. Valves hold well but check them at the interval in the table and any time the bike gets hard to start hot. Plan on a piston around 40 to 50 hours for a race bike. Check the air fork pressure before every ride and grease the linkage after wet rides.

Engine hours between jobs: the schedule the Digital Garage tracks for this bike, based on the manual. Racers and hard riders go sooner, as above. Ride in sand or mud and halve the engine ones.

JobEvery
Air filter3h
Engine oil & filter15h
Gearbox oil15h
Valve clearance45h
Coolant flush60h

Parts that fit a 250 SX-F

Everything that fits a 250 SX-F →

Buying a used KTM 250 SX-F

Ask about hours, the last piston and the last valve check, and get receipts. Make sure it starts on the button hot and cold and the hydraulic clutch has a firm lever. Check the air fork holds pressure. Pull the seat and look at the airbox. Check the frame around the footpeg mounts and the subframe on a bike that has been raced by a junior.

Recent sold prices for each year are on the Marketplace page linked below.

Used KTM 250 SX-Fs for sale

3 listed on the MWMX Marketplace right now.

All KTM 250 SX-Fs for sale and recent sold prices →

KTM 250 SX-F known issues

KTM 250 SX-F questions

How often should I change the oil in a 250 SX F?
Every 5 to 8 hours if it is raced, with a filter every second change.
Is the 250 SX F a good first race bike?
For a fast junior coming off an 85 or 125, yes. For a beginner, a YZ250F is more forgiving.
250 SX F or 250 EXC F?
The SX F is the motocross bike with a close ratio gearbox and stiff suspension. The EXC F is the registrable enduro bike.
What oil does a KTM 250 SX F take?
A JASO MA full synthetic, 10W 60 or 10W 50, about a litre with a filter.

Other KTM models

KTM 250 SX-F Guide: Years, Servicing, Known Issues and Used 250 SX-Fs for Sale | MWMX