SKF Fork Oil Seal 43x52.9x9.5 mm for KTM, HUSABERG, HUSQVARNA and GAS GAS 2000-2026

The SKF 43x52.9x9.5 mm OSB-43W fork oil seal is designed for KTM EXC 125, EXC 200, EXC 250, EXC 300, EXC 380, EXC 400, EXC 520, EXE 125, FREERIDE 250, FREERIDE 350, LC4 640, MXC 200, MXC 300, MXC 380, MXC 400, MXC 520, SC 400, SX 85, SX 105, SX 125, SX 200, SX 250, SX 380, SX 400, SX 520, SXC 400, SXC 625, XC 85, XC 105, HUSABERG FC 400, FC 470, FC 550, FE 400, FE 501, FE 650, FS 400, FS 650, FX 470, FX 650, GAS GAS ECF 450, MC 85, MC 125 and HUSQVARNA NORDEN 901, TC 85 from 2000 to 2026. The fork oil seal keeps the oil inside the fork leg while letting the inner tube slide. It is a wear item: dust, mud and impacts on the tubes eventually damage its lip, and the fork leaks.

Specifications

• Brand: SKF
• Manufacturer part number: OSB-43W
• EAN code: 8050040143726
• Weight: 20 g

When to replace it?

• Film of oil on the inner tube after a few fork strokes.
• Oil traces on the fork leg, the caliper or the brake disc.
• Fork that becomes softer on one side.

Before replacing a leaking seal, clean under its lip: a trapped grain of sand is sometimes enough to cause the leak. If it still leaks, replace the seals on both legs. Measure your seal (inside diameter, outside diameter and height) or check the original part number: the size is in the name.

Fitting tips

1. Drain and disassemble the fork leg following the manual, then remove the dust seal, the circlip and the old seal.
2. Check the fork bushings and the condition of the inner tube: a scratch or a rust spot will cut a new seal.
3. Protect the end of the tube (plastic bag), oil the lip and drive the seal in straight with a seal driver of the right diameter.
4. Refit the circlip and a new dust seal, then reset the fork oil level.

Why SKF?

SKF is renowned for its fork seals, among the most durable in motocross according to the American magazine Motocross Action, which notes that the WP forks on KTMs are fitted with them as original equipment. In its Dual Compound range, the brand combines two rubber compounds moulded together: a tough green dust wiper and a softer red sealing lip, both reinforced by a metal insert.

Spare parts and items to plan

• Fork dust seals : ATHENA P40FORK455125 · ATHENA P40FORK455179
• Fork oil : LIQUI MOLY 10W 500 ml
• Fork bushings : INNTECK SKTI43W · INNTECK SKTE43W

Frequently asked questions

Do I have to change both seals?
Yes: they have the same age and the same mileage. Replace both oil seals and, ideally, both dust seals.

Why is my new seal leaking?
Most often because of a scratched or pitted tube, a lip turned back during installation, or worn bushings that let the tube develop play.

Compatibility

Check the exact model and year of your bike in the list below before ordering.

Fits:
GAS GAS ECF 450 2007
GAS GAS ECF 450 2006
GAS GAS ECF 450 2005
GAS GAS ECF 450 2004
GAS GAS ECF 450 2003
GAS GAS MC 85 2025
GAS GAS MC 85 2024
GAS GAS MC 85 2023
GAS GAS MC 85 2022
GAS GAS MC 85 2021
GAS GAS MC 125 2003
HUSABERG FC 400 2001
HUSABERG FC 400 2000
HUSABERG FC 470 2001
HUSABERG FC 470 2000
HUSABERG FC 550 2001
HUSABERG FC 550 2000
HUSABERG FE 400 2001
HUSABERG FE 400 2000
HUSABERG FE 501 2001
HUSABERG FE 501 2000
HUSABERG FE 650 2001
HUSABERG FE 650 2000
HUSABERG FS 400 2001
HUSABERG FS 400 2000
HUSABERG FS 650 2001
HUSABERG FS 650 2000
HUSABERG FX 470 2001
HUSABERG FX 470 2000
HUSABERG FX 650 2001
HUSABERG FX 650 2000
HUSQVARNA NORDEN 901 2025
HUSQVARNA NORDEN 901 2024
HUSQVARNA NORDEN 901 2023
HUSQVARNA NORDEN 901 2022
HUSQVARNA TC 85 2025
HUSQVARNA TC 85 2024
HUSQVARNA TC 85 2023
HUSQVARNA TC 85 2022
HUSQVARNA TC 85 2021
HUSQVARNA TC 85 2020
HUSQVARNA TC 85 2019
HUSQVARNA TC 85 2018
HUSQVARNA TC 85 2017
HUSQVARNA TC 85 2016
HUSQVARNA TC 85 2015
HUSQVARNA TC 85 2014
KTM EXC 125 2002
KTM EXC 125 2001
KTM EXC 125 2000
KTM EXC 200 2002
KTM EXC 200 2001
KTM EXC 200 2000
KTM EXC 250 2002
KTM EXC 250 2001
KTM EXC 250 2000
KTM EXC 300 2002
KTM EXC 300 2001
KTM EXC 300 2000
KTM EXC 380 2002
KTM EXC 380 2001
KTM EXC 380 2000
KTM EXC 400 2002
KTM EXC 400 2001
KTM EXC 400 2000
KTM EXC 520 2002
KTM EXC 520 2001
KTM EXC 520 2000
KTM EXE 125 2001
KTM EXE 125 2000
KTM FREERIDE 250 2017
KTM FREERIDE 250 2016
KTM FREERIDE 250 2015
KTM FREERIDE 250 2014
KTM FREERIDE 350 2017
KTM FREERIDE 350 2016
KTM FREERIDE 350 2015
KTM FREERIDE 350 2014
KTM FREERIDE 350 2013
KTM FREERIDE 350 2012
KTM LC4 640 2004
KTM LC4 640 2003
KTM LC4 640 2000
KTM MXC 200 2002
KTM MXC 200 2001
KTM MXC 200 2000
KTM MXC 300 2002
KTM MXC 300 2001
KTM MXC 300 2000
KTM MXC 380 2002
KTM MXC 380 2001
KTM MXC 380 2000
KTM MXC 400 2002
KTM MXC 400 2001
KTM MXC 520 2002
KTM MXC 520 2001
KTM SC 400 2000
KTM SX 85 2026
KTM SX 85 2025
KTM SX 85 2024
KTM SX 85 2023
KTM SX 85 2022
KTM SX 85 2021
KTM SX 85 2020
KTM SX 85 2019
KTM SX 85 2018
KTM SX 85 2017
KTM SX 85 2016
KTM SX 85 2015
KTM SX 85 2014
KTM SX 85 2013
KTM SX 85 2012
KTM SX 85 2011
KTM SX 85 2010
KTM SX 85 2009
KTM SX 85 2008
KTM SX 85 2007
KTM SX 85 2006
KTM SX 85 2005
KTM SX 85 2004
KTM SX 85 2003
KTM SX 105 2011
KTM SX 105 2010
KTM SX 105 2009
KTM SX 105 2008
KTM SX 105 2007
KTM SX 105 2006
KTM SX 125 2002
KTM SX 125 2001
KTM SX 125 2000
KTM SX 200 2002
KTM SX 200 2001
KTM SX 200 2000
KTM SX 250 2002
KTM SX 250 2001
KTM SX 250 2000
KTM SX 380 2002
KTM SX 380 2001
KTM SX 380 2000
KTM SX 400 2001
KTM SX 400 2000
KTM SX 520 2001
KTM SX 520 2000
KTM SXC 400 2000
KTM SXC 625 2004
KTM SXC 625 2003
KTM XC 85 2009
KTM XC 85 2008
KTM XC 105 2009
KTM XC 105 2008