ATHENA Piston Ring Set Ø95 mm for YAMAHA WRF 450, YZF 450 2003-2016

On YAMAHA WRF 450, YZF 450 from 2003 to 2016, the ATHENA S41316212 set of piston rings (Ø 95 mm) fits in place of the original part. Thin and heavily loaded, the rings seal between the piston and the cylinder. They are often the first parts to wear: new rings bring compression back to an engine whose piston and cylinder are still within spec.

Specifications

• Brand: ATHENA
• Manufacturer part number: S41316212
• EAN code: 8050043262820
• For ATHENA piston
• Diameter: 95 mm
• Weight: 30 g
• Engine: 4-stroke

When to replace it?

• Loss of compression and power, harder starting.
• Ring end gap, measured in the cylinder, larger than the figure in the manual.
• Ring stuck in its groove or showing traces of blow-by.
• On a four-stroke: oil consumption and blue smoke.

At every top end inspection, and at the latest when the piston is replaced. On a piston that is still within spec, new rings at mid-life bring the compression back. As a Cross-Mania guideline, the complete piston is replaced every 30 to 60 hours of engine running depending on whether you race or ride for fun.

Fitting tips

1. Clean the piston grooves (a broken old ring makes a good scraper) without widening them.
2. Place each ring in the cylinder, pushed in square with the piston, and measure its end gap with a feeler gauge.
3. Open the rings just enough to slip them over the piston, by hand or with ring pliers: opened too far, they distort or break.
4. Mark facing up, gaps staggered by about 120°, without overlapping the ends of the oil control ring.
5. Lightly oil the cylinder and the rings before reassembly, with a new top end gasket kit.

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

• Piston : PROX · WISECO
• Top-end gasket kit : see the selection
• Piston pin : ATHENA
• Piston pin clips : WISECO
• Spark plug : NGK 4218 · NGK 96067

Frequently asked questions

Which diameter should I choose?
The nominal diameter of your piston, given in the title. The rings go on a piston of the same bore size.

Does the engine need breaking in?
Yes: one hour of gentle break-in, without sustained full throttle, so the rings bed in to the cylinder.

Compatibility

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

Fits:
YAMAHA WRF 450 2016
YAMAHA WRF 450 2015
YAMAHA WRF 450 2014
YAMAHA WRF 450 2013
YAMAHA WRF 450 2012
YAMAHA WRF 450 2011
YAMAHA WRF 450 2010
YAMAHA WRF 450 2009
YAMAHA WRF 450 2008
YAMAHA WRF 450 2007
YAMAHA WRF 450 2006
YAMAHA WRF 450 2005
YAMAHA WRF 450 2004
YAMAHA WRF 450 2003
YAMAHA YZF 450 2015
YAMAHA YZF 450 2014
YAMAHA YZF 450 2013
YAMAHA YZF 450 2012
YAMAHA YZF 450 2011
YAMAHA YZF 450 2010
YAMAHA YZF 450 2009
YAMAHA YZF 450 2008
YAMAHA YZF 450 2007
YAMAHA YZF 450 2006
YAMAHA YZF 450 2005
YAMAHA YZF 450 2004
YAMAHA YZF 450 2003