The Polaris 850 with its huge 74mm stroke was just asking for a bigger bore and we have done our homework to bring you the 900cc Big Bore

Gains 1-2 peak horsepower with even better low to mid range grunt

Direct fit replacement

With the torsion spring full shift out is achieved

stock-style compression spring we offer has a much better rate and is designed to work with our custom helix

Billet Head Dome / Polaris Category_Default Category/SXS/Polaris RZR/RZR XP Turbo 2017-20 The Polaris 850 with itsReplacement Domes for the Bmp Billet Head. Change your compression for different riding elevations and motor applications. Price is Per Dome Polaris 800 Low Altitude 04 311 800 41 Polaris 800 High Altitude 04 311 800 37. 5 Polaris 850 Low Altitude 04 318 850 40. 5 Polaris 850 High Altitude 04 318 850 36. 5 Polaris 900 Low Altitude 04 318 900 42 Polaris 900 High Altitude 04 318 900 37