ATHENA Top End Gasket Kit without valve cover gasket for KTM, HUSQVARNA and GAS GAS 2023-2027

The ATHENA P400270600094 top end gasket kit is designed for KTM EXCF 450, EXCF 500, SXF 450, XCF 450, XCFW 450, HUSQVARNA FC 450, FE 450, FE 501, FS 450, FX 450 and GAS GAS EXF 450, MCF 450 from 2023 to 2027. The top end gasket kit brings together the gaskets to replace every time the cylinder head or cylinder comes off. A gasket crushed by tightening never gets its shape back: refitting it means risking a compression, coolant or oil leak, and having to strip everything down again.

Key features

• Head, base and exhaust gaskets, O-rings and washers, depending on the model.
• Laser cutting and surface treatments for consistent sealing.
• Designed by Athena, an OEM supplier, and validated on test benches.

Specifications

• Brand: ATHENA
• Manufacturer part number: P400270600094
• EAN code: 8053300717163
• Weight: 110 g
• Engine: 4-stroke

When to replace it?

• Coolant or oil seeping at the head/cylinder or cylinder/crankcase joint.
• Coolant level dropping, bubbles in the radiator.
• Hissing or black marks where the exhaust leaves the cylinder.

At every piston change and every time the cylinder head or cylinder is removed, even for a simple inspection. Gaskets cost little compared with the work of stripping the engine.

Fitting tips

1. Clean the gasket faces without scratching them (plastic scraper, solvent): they must be clean, dry and free of burrs.
2. Fit the gaskets dry, without sealant, unless the workshop manual says otherwise.
3. Refit a base gasket of the same thickness as the old one, unless you are deliberately adjusting the squish.
4. Tighten the cylinder head in a criss-cross pattern, in several stages, up to the manufacturer's torque.
5. While it's apart, replace the spark plug and refill the coolant.
6. After break-in, check the torque with the engine cold and make sure there are no leaks.

Why ATHENA?

Athena, an Italian company founded in 1973 near Vicenza, designs gaskets, pistons and cylinder kits for motorcycles. An OEM supplier to KTM, Ducati, Fantic, Piaggio and Triumph and a partner of the MXGP world championship, it develops its parts on the test bench and on the track with racing teams.

Spare parts and items to plan

• Piston : VERTEX 23849 · VERTEX 23850
• Piston rings : WOSSNER · PROX
• Spark plug : NGK 3521 · NGK 97225
• Coolant : LIQUI MOLY 1 L · TWIN AIR
• 4-stroke engine oil : LIQUI MOLY 10W40 1 L · MOTUL 10W50

Frequently asked questions

What does the kit contain?
Depending on the model: head gasket, base gasket, exhaust gasket, O-rings and washers. Compare with your original gaskets if you're unsure.

Should I replace it along with the piston?
Yes: as soon as the cylinder head and cylinder are off, new gaskets go back on. It's the right time to fit a new piston kit and new rings if the engine has some hours on it.

Compatibility

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

Fits:
GAS GAS EXF 450 2025
GAS GAS EXF 450 2024
GAS GAS MCF 450 2027
GAS GAS MCF 450 2026
GAS GAS MCF 450 2025
GAS GAS MCF 450 2024
HUSQVARNA FC 450 2027
HUSQVARNA FC 450 2026
HUSQVARNA FC 450 2025
HUSQVARNA FC 450 2024
HUSQVARNA FC 450 2023
HUSQVARNA FE 450 2027
HUSQVARNA FE 450 2026
HUSQVARNA FE 450 2025
HUSQVARNA FE 450 2024
HUSQVARNA FE 501 2027
HUSQVARNA FE 501 2026
HUSQVARNA FE 501 2025
HUSQVARNA FE 501 2024
HUSQVARNA FS 450 2027
HUSQVARNA FS 450 2026
HUSQVARNA FS 450 2025
HUSQVARNA FS 450 2024
HUSQVARNA FS 450 2023
HUSQVARNA FX 450 2025
HUSQVARNA FX 450 2024
HUSQVARNA FX 450 2023
KTM EXCF 450 2027
KTM EXCF 450 2026
KTM EXCF 450 2025
KTM EXCF 450 2024
KTM EXCF 500 2027
KTM EXCF 500 2026
KTM EXCF 500 2025
KTM EXCF 500 2024
KTM SXF 450 2027
KTM SXF 450 2026
KTM SXF 450 2025
KTM SXF 450 2024
KTM SXF 450 2023
KTM XCF 450 2027
KTM XCF 450 2026
KTM XCF 450 2025
KTM XCF 450 2024
KTM XCF 450 2023
KTM XCFW 450 2027
KTM XCFW 450 2026
KTM XCFW 450 2025
KTM XCFW 450 2024