Piston stock bore Kit "RACING" by GRT 660cc 81mm
SKU: MB00115-GRT-BIG-BORE-KIT
Product Description
This kit includes two high-performance racing pistons with an 81 mm bore, manufactured from forged aluminium for enhanced strength and durability. Featuring an increased compression ratio of 14.2:1 (compared to the standard 13.5:1), these pistons require the use of at least 100 octane fuel (EU specification).
Compatibility & Intended Use
Designed for the Aprilia RS660 (2021–2026) and Tuono 660 models, this is a race-oriented product. Professional installation is strongly recommended, including correct ring gap setting and thorough piston-to-valve clearance checks.
Technical Specifications
The single-ring design, combined with enlarged valve pockets, enables compatibility with oversized exhaust valve kits (available at this link: Oversized valves kit by GRT for exhaust 675 ).
Please note that the kit reuses several original components, including the compression ring, oil control ring, piston pin, circlips, and cylinder head gasket. These parts are not included, but we can source them, feel free to ask!
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