The Namura NA-50015-2 piston kit is designed for select 50cc Yamaha and Polaris ATV applications. This oversized piston measures 39.48 mm, equivalent to a +0.50 mm oversize, and is intended for use with a cylinder that has been properly bored and honed to match the piston specification. It provides a replacement solution for worn or damaged piston assemblies when rebuilding compatible engines.
Fitment includes the 2017 Yamaha YFZ50 and Polaris Outlaw 50 models from 2008 through 2016. Verify the engine model, year, cylinder bore, and required oversize before installation. The Namura manufacturer part number is NA-50015-2, and the vendor part number is 187-500152.
This kit is not compatible with OEM piston rings, and the included or corresponding rings will not work with the OEM piston. Use rings specifically matched to the Namura NA-50015-2 piston and confirm all clearances, ring end gaps, and installation procedures against the applicable service information. Proper machine work and measurement are required for reliable fitment and engine performance.
Features:
- Size: 39.48 mm piston diameter, equivalent to a +0.50 mm oversize
- Model: Piston kit for select Yamaha YFZ50 and Polaris Outlaw 50 applications
- Brand: Namura
- Manufacturer Part Number: NA-50015-2
- Vendor Part Number: 187-500152
- Fitment: 2017 Yamaha YFZ50 and 2008–2016 Polaris Outlaw 50
- Compatibility: Does not accept OEM rings, and the corresponding rings will not work with the OEM piston
- Installation: Requires a properly bored and honed cylinder matched to the piston specification
Fitment:
2007 Polaris Predator 50
2008 Polaris Outlaw 50
2009 Polaris Outlaw 50
2010 Polaris Outlaw 50
2011 Polaris Outlaw 50
2012 Polaris Outlaw 50
2013 Polaris Outlaw 50
2014 Polaris Outlaw 50
2015 Polaris Outlaw 50
2016 Polaris Outlaw 50
2017 Polaris Outlaw 50
2017 Yamaha YFZ50
2018 Polaris Outlaw 50
2018 Yamaha YFZ50
2019 Polaris Outlaw 50
2019 Yamaha YFZ50