850 Patriot Features
- So perhaps one of the most impressive features of the new powerplant is so confident is the company in its new 850 Patriot that Polaris is offering a 4 year warranty on the engine.
- As one Polaris official told us, power wasn’t even in the top 5 of targeted goals with the new engine. Durability and responsiveness were the primary goals.
- The new piston design has a 3 mm thicker dome while the compression height has been bumped up 8 mm. Also, there is more contact area (23 percent more compared to the 800) with the cylinder bore which maximizes heat transfer. There is a higher capacity wrist pin and PVD-coated steel single ring design. The single ring design is a first for Polaris and we were told the steel ring was the way to go to increase durability.
- The new, lightweight crankshaft has a larger clutch taper (for durability and serviceability) and utilized symmetrical press fit webs for improved straightness. Separate crankpins feature a high-grade material (Case Carburized SNCM 420H) with the crank also using a higher capacity bearing and pin design.
- Along with the new piston and crankshaft the 850 Patriot has a new cylinder and cylinder head featuring a one-piece head design and 6 bolt cylinder structure that was optimized with Finite Element Analysis. This new structure (patent-pending) has a exhaust port design offering high-flow intake and exhaust ports. The one-piece head design is also important for structural rigidity and helps with Polaris’ new coolant flow.
- The Advanced Cooling System results in high velocity coolant flow around the cylinder bore, combustion chamber and exhaust valves. As part of the new cooling system, the 850 Patriot has a new water bottle with integrated thermostat which minimizes vibration and, thus, extends the life of the thermostat. As part of the new water bottle, there is an integrated bypass for faster warm up and the cooling system is self-bleeding.
- The new lightweight throttle body is a simple design that features a contact-less Throttle Position Sensor (TPS) for reliable and consistent performance.
- The new 3-stage E-VES-II Exhaust Valve System uses a simplified coplanar valve with fewer parts and an EV base that is lightweight because of its die-cast magnesium design. The improved fit and sealing to the piston and exhaust ports help control exhaust flow while optimizing the engine’s performance.
- There is a new pipe and resonator, improving flow and sound quality as well as a new fuel system and temp sensor that has a host of benefits such as improving piston durability, increasing control of variability in fueling, improved starting in all conditions, improved diagnostic functionality and better engine protection in case of low fuel pressure.
- New VForce Reeds were designed specifically for the 850 Patriot and have carbon fiber petals for improved performance and a reed block that has an industry exclusive secondary seal on the inner cage for durability.