ATHENA Cylinder Base Gasket for YAMAHA XT 660, APRILIA PEGASO 650 and KTM SX 125 1984-2012

The ATHENA S410010006019 cylinder base gasket is designed for KTM SX 125, YAMAHA XT 660 and APRILIA PEGASO 650 from 1984 to 2012. The base gasket seals between the cylinder and the crankcase. Its thickness matters: it sets the height of the cylinder, and therefore the squish, the compression and, on a two-stroke, the port timing.

Key features

• Several thicknesses available for the same bike.
• The right tool for setting squish, compression and timing, according to Athena.

Specifications

• Brand: ATHENA
• Manufacturer part number: S410010006019
• EAN code: 8051757033621
• Thickness: OE
• Weight: 50 g

When to replace it?

• Oil or coolant seeping at the base of the cylinder.
• Gasket crushed or torn on removal.

Every time the cylinder is removed: a crushed base gasket can't be reused.

Fitting tips

1. Clean the crankcase face and the base of the cylinder without scratching them.
2. Fit the gasket dry, centred on the studs.
3. Tighten the cylinder in a criss-cross pattern to the manufacturer's torque.
4. If you have changed the thickness, measure the squish before refitting the cylinder head with a new head gasket.

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

• Top-end gasket kit : ATHENA P400010600026 · ATHENA S410010001011
• Piston : see the selection
• Piston rings : PROX · VERTEX
• Coolant : LIQUI MOLY 1 L · TWIN AIR

Frequently asked questions

Which thickness should I choose?
The same as your original gasket, unless you are deliberately adjusting the squish.

Should the other gaskets be replaced?
Yes, as soon as the cylinder is removed: a top end gasket kit includes all the gaskets that need replacing.

Compatibility

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

Fits:
APRILIA PEGASO 650 2009
APRILIA PEGASO 650 2008
APRILIA PEGASO 650 2007
APRILIA PEGASO 650 2006
APRILIA PEGASO 650 2005
KTM SX 125 1986
KTM SX 125 1985
KTM SX 125 1984
YAMAHA XT 660 2012
YAMAHA XT 660 2011
YAMAHA XT 660 2010
YAMAHA XT 660 2009
YAMAHA XT 660 2008
YAMAHA XT 660 2007
YAMAHA XT 660 2006
YAMAHA XT 660 2005
YAMAHA XT 660 2004