This is the OS 55HZ Hyper Ringed Helicopter Engine with the 40L Carburetor. New $299.97 (40% off). Features: * Ideal for 3D flight-power equal to .60 size heli engines. * Same mounting bolt pattern and silencer size as the OS 50SX-H Hyper. * Dual needle 40L carburetor allows independent adjustment of idling hovering and high speed with four arm throttle lever for use wit a variety of servo brands. * HZ Hyper low profile black aluminum six fin cylinder head. * Two year limited warranty through manufacturer beginning at the dat of purchase.

This is the Red Line RL-1.00 Ringed Heli Engine from Thunder Tiger. New $299.97 (33% off). Features: * XC2 (Extreme Composite Coating) cylinder liner etched with specia criss cross pattern. * Designed for stable hovering and thrilling 3D manuevers in .50 .90 size helicopters. * Precision balanced crankshaft is nickel plated to reduce corrosion. * Lightened hypereutetic machined Al-Si ringed piston. * Knife edge, high strength connecting rod. * Two needle valve carburetor with both hex and FT driver head at sam side for easy adjustment, push/pull throttle lever pre-installed. * Machined aluminum oversized heat sink head. * Three year limited warranty beginning at date of purchase.

This is the RL-53H Ringed Redline Series Two Stroke Helicopter Engine from Thunder Tiger.:. New $229.98 (23% off). Features: * CNC construction low profile cylinder head, anodized red in color.:. * Fixed type two-needle carburetor with two mounting bolts, push/pul throttle lever and heat insulator for consistent performance unde different flying conditions and cowl enclosures.:. * Lightened hypereutectic machined Al-Si ringed type piston.:. * XC2 (extreme composite) cylinder liner coating with a criss-cros pattern etched on the sleeve wall.:. * Knife-edged high-strength connecting rod with bushings.:. * Redline R3 glowplug with platinum alloy filament.:. * Reinforced resin rear cage ball bearing

This is the 105HZ-R DRS 1.05 cu in Helicopter Engine from O.S. New $529.99 (33% off). Engines. Features: * Same mounting dimensions as a .90 cu in engine. * Machined blue anodized aluminum heatsink cylinder head. * Velocity stack increases airflow and enhances engine performance. * Pressurized DRS (Demand Regulator System) ensures consistent fue flow regardless of the helicopter attitude. * Backplate accepts the Futaba BPS-1 RPM sensor for the GY701 an CGY750 gyros. * Ideal bore and stroke ratio for lowest vibration. * Two year limited warranty through Hobby Services beginning at date o purchase.

This is the 105HZ 1.05 cu in Helicopter Engine from O.S. New $479.97 (31% off). Engines. Features: * Same mounting dimensions as a .90 cu in engine. * Machined blue anodized aluminum heatsink cylinder head. * Velocity stack increases airflow and enhances engine performance. * Backplate accepts the Futaba BPS-1 RPM sensor for the GY701 an CGY750 gyros. * Ideal bore and stroke ratio for lowest vibration. * Two year limited warranty through Hobby Services beginning at date o purchase.

This is the O.S. New $399.99 (38% off). .91HZ F3C Competition Helicopter Engine.:. Features: * Designed specifically for F3C aerobatic competition.:. * Rectangular heat sink allows engine to be enclosed entirely insid cooling shroud.:. * 61-E carburetor with thermal insulator to block heat and a needl valve control lever to control mixture from transmitter, carbureto has three adjustment controls that enable independent adjustment a idling, hovering and high speed.:. * Five holes in the top of the piston route gases to the piston rin from within to form a tighter seal with minimum blow by.:. * Ball bearing supported crankshaft.:. * Heat sink type backplate.:. * Two year limited warranty through H

This is the O.S. New $369.99 (53% off). Engines 91 HZ-R 3C Speed Helicopter Engine in Red. ****** Because of the competition nature of this engine,****** ******it is NOT covered by the O.S. 2 Year Warranty.******. Features: * Designed for all-out F3C competition. * Demand Regulator System ensures consistent fuel delivery from ful to empty. * 170° exhaust timing for optimal horsepower and stable hovering. * Newly designed combustion chamber shaped to match the big bor carburetor and advanced exhaust cylinder timing. * 0.44" (11.2mm) Big Bore 61G carburetor for greatest power neede for F3C maneuvers. * Crankshaft counter-weight reduces vibration at high RPM.

This is the O.S. New $669.99 (39% off). Engines 91 HZ-R 3D Speed Helicopter Engine in Black with the 91 PowerBoost Tuned Pipe.:. ****** Because of the competition nature of this engine,****** ******it is NOT covered by the O.S. 2 Year Warranty.******:. Features: * Designed for all-out 3D competition.:. * DRS (Demand Regulator System) ensures a steady fuel supply for 3 flights.:. * 165° exhaust timing for optimal horsepower and stable hovering.:. * Newly designed combustion chamber shaped to match the big bor carburetor and advanced exhaust cylinder timing.:. * 61G Big Bore twin needle carburetor is designed to develope stabl horsepower at 70-80% throttle which is widely used in 3D flight.:. *

This is the O.S. New $424.98 (46% off). Engines 91 HZ-R 3D Speed Helicopter Engine in Black.:. ****** Because of the competition nature of this engine,****** ******it is NOT covered by the O.S. 2 Year Warranty.******:. Features: * Designed for all-out 3D competition.:. * Demand Regulator System ensures consistent fuel delivery from ful to empty.:. * 165° exhaust timing for optimal horsepower and stable hovering.:. * Newly designed combustion chamber shaped to match the big bor carburetor and advanced exhaust cylinder timing.:. * 61F Big Bore carburetor is designed to develope stable horsepower a 70-80% throttle which is widely used in 3D flight.:. * Crankshaft counter-weight reduces vibration

This is the Limited Edition OS 55HZ-R DRS Ringed Helicopter Engine with the DRS (Demand Regulator System). New $399.99 (33% off). Features: * DRS system delivers fuel to the regulator under constant pressur for precise fuel delivery throughout the entire tank from full t empty. * Mounting position of DRS is perfectly in line with the carb fo consistent operation in all attitudes of flight. * Same mounting bolt pattern as the OS 50SX-H Hyper. * Dual needle 40L-R carburetor allows independent adjustment of idling hovering and high speed with four arm throttle lever for use wit a variety of servo brands. * HZ Hyper low profile six fin cylinder head. * Two year limited warranty through Hobby Services

This is the Thunder Tiger RL .56H Ringed Helicopter Engine.:. New $229.98 (34% off). Features: * XC2 composite coating on cylinder liner to extend engine life an an etched criss-cross pattern to minimize friction.:. * Dual needle carburetor with a heat insulator mount and push-pul throttle lever.:. * Oversized CNC machined red anodized cylinder head.:. * Three year limited warranty through Hobby Services beginning at dat of purchase.:.