ATHENA Top End Gasket Kit for ATHENA standard bore cylinder kit for KTM, HUSQVARNA and GAS GAS 2016-2023

The ATHENA P400270160078 top end gasket kit is designed for KTM EXCF 250, SXF 250, XCF 250, HUSQVARNA FC 250, FE 250 and GAS GAS EXF 250, MCF 250 from 2016 to 2023. As soon as the cylinder head or cylinder is removed, their gaskets must be replaced: crushed when tightened, they have taken the shape of the parts and will no longer seal. This kit groups under one part number the gaskets needed to reassemble the top end.

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: P400270160078
• EAN code: 8052780275927
• For ATHENA cylinder kit ref. EC270-020 (Ø78 mm), P400270100020 (Ø78 mm), P400270100022 (Ø78 mm)
• Weight: 100 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?

Founded in 1973 near Vicenza, Athena is an Italian engine gasket specialist that has made its gaskets on its own production lines since day one, as well as a renowned manufacturer of pistons and cylinder kits. The brand supplies original equipment to manufacturers such as KTM, Ducati, Fantic, Piaggio and Triumph, and is a partner of the MXGP motocross world championship.

Spare parts and items to plan

• ATHENA cylinder kit : ATHENA EC270-020 · ATHENA P400270100020 · ATHENA P400270100022
• Piston : ATHENA S5F07800002 · ATHENA S5F07800002A · ATHENA S5F07800001
• Spark plug : NGK 3521 · NGK 97225
• Coolant : LIQUI MOLY 1 L · TWIN AIR
• 4-stroke engine oil : MOTUL 10W50 · LIQUI MOLY 10W40 1 L

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 250 2023
GAS GAS EXF 250 2022
GAS GAS EXF 250 2021
GAS GAS MCF 250 2023
GAS GAS MCF 250 2022
GAS GAS MCF 250 2021
HUSQVARNA FC 250 2022
HUSQVARNA FC 250 2021
HUSQVARNA FC 250 2020
HUSQVARNA FC 250 2019
HUSQVARNA FC 250 2018
HUSQVARNA FC 250 2017
HUSQVARNA FC 250 2016
HUSQVARNA FE 250 2019
HUSQVARNA FE 250 2018
HUSQVARNA FE 250 2017
KTM EXCF 250 2019
KTM EXCF 250 2018
KTM EXCF 250 2017
KTM SXF 250 2022
KTM SXF 250 2021
KTM SXF 250 2020
KTM SXF 250 2019
KTM SXF 250 2018
KTM SXF 250 2017
KTM SXF 250 2016
KTM XCF 250 2022
KTM XCF 250 2021
KTM XCF 250 2020
KTM XCF 250 2019
KTM XCF 250 2018
KTM XCF 250 2017
KTM XCF 250 2016