ATHENA Cast Piston for KTM SX 85, XC 85, HUSQVARNA TC 85 and GAS GAS MC 85 2003-2026

ATHENA offers this piston kit for KTM SX 85, XC 85, HUSQVARNA TC 85 and GAS GAS MC 85 2003-2026. The piston slides in the cylinder and takes the force of the air-fuel combustion, passing it to the connecting rod and crankshaft.

Why a cast piston?

A cast piston is moulded from a high-silicon aluminium alloy, then machined.

• Low expansion: it runs with a tight clearance, stays quiet when cold and warms up quickly.
• Durability: an excellent choice for a stock engine used for leisure or enduro.
• Price: more affordable than a forged piston.
• Good to know: it copes less well with overheating and extreme revs than a forged one.

Why choose ATHENA?

Athena, the Italian manufacturer founded in 1973, is an original-equipment supplier to manufacturers such as KTM and Ducati: the same standards for your replacement parts.

When should you replace the piston on your KTM SX 85?

Harder starting, loss of power, blue smoke, oil consumption or a knock when cold: these are the signs of a tired top end.

No manufacturer hour figure for this model. Cross-Mania guideline: compression check every 15 h in hard use and every 30 h for leisure.

Specifications and fitting tips

• Engine: 2-stroke
• Manufacturer part numbers: S4C04700005A (A), S4C04700005B (B), S4C04700005C (C), S4C04700005D (D)

Available in several sizes: choose the one that matches your cylinder (stamped size or measured bore). Diameters: A = 46.94 mm, B = 46.95 mm, C = 46.96 mm, D = 46.97 mm.

Spare parts and items to plan

• Piston rings : ATHENA · PROX
• Piston pin : WISECO · WOSSNER
• Piston pin clips : WISECO 125 L
• Top-end gasket kit : ATHENA M752005400094 · ATHENA M752008000094
• Small end needle bearing : PROX · ATHENA
• Spark plug : NGK 2707 · NGK 3006
• Coolant : LIQUI MOLY 1 L · TWIN AIR
• 2-stroke oil : LIQUI MOLY 1 L · LIQUI MOLY 4 L

Compatibility

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

Fits:
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
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 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 XC 85 2012
KTM XC 85 2011
KTM XC 85 2010
KTM XC 85 2009
KTM XC 85 2008