The HKS 700E is a twin-cylinder, horizontally opposed,

four stroke A four-stroke (also four-cycle) engine is an internal combustion (IC) engine in which the piston completes four separate strokes while turning the crankshaft. A stroke refers to the full travel of the piston along the cylinder, in either directi ...

, carburetted aircraft engine, designed for use on ultralight aircraft,

powered parachute A powered parachute, often abbreviated PPC, and also called a motorized parachute or paraplane, is a type of aircraft that consists of a parafoil with a motor and wheels. The FAA defines a powered parachute as ''a powered aircraft a flexible o ...

s and

ultralight trike An ultralight trike is a type of powered hang glider where flight control is by weight-shift. These aircraft have a fabric flex-wing from which is suspended a tricycle fuselage pod driven by a pusher propeller. The pod accommodates either a ...

s. The engine is manufactured by HKS, a Japanese company noted for its automotive racing engines.Cliche, Andre: ''Ultralight Aircraft Shopper's Guide'' 8th Edition, page G-9 Cybair Limited Publishing, 2001.

Development

The HKS 700E has dual

capacitor discharge ignition Capacitor discharge ignition (CDI) or thyristor ignition is a type of automotive electronic ignition system which is widely used in outboard motors, motorcycles, lawn mowers, chainsaws, small engines, turbine-powered aircraft, and some cars. It ...

, dual carburetors and electric start. The engine is mainly

air-cooled Air-cooled engines rely on the circulation of air directly over heat dissipation fins or hot areas of the engine to cool them in order to keep the engine within operating temperatures. In all combustion engines, a great percentage of the heat ge ...

, but with oil-cooled cylinder heads. The OHV pushrod engine has four valves per cylinder, and nickel-ceramic coated cylinder bores. Lubrication is

dry sump A dry-sump system is a method to manage the lubricating motor oil in four-stroke and large two-stroke piston driven internal combustion engines. The dry-sump system uses two or more oil pumps and a separate oil reservoir, as opposed to a con ...

, with a

trochoid pump A gerotor is a positive displacement pump. The name ''gerotor'' is derived from "generated rotor". A gerotor unit consists of an inner and outer rotor. The inner rotor has ''n'' teeth, while the outer rotor has ''n''+1 teeth; with ''n'' defined a ...

. The reduction drive is a choice of two integral gearboxes: the A-type gearbox has a 2.58:1 ratio and can accommodate propellers of up to 4,000 kg/cm2 inertial load; the B-type gearbox has a 3.47:1 ratio and can accommodate propellers of up to 6,000 kg/cm2. The 700E burns per hour in cruise flight at 4,750 rpm. The recommended

time between overhaul Time between overhauls (abbreviated as TBO or TBOH) is the manufacturer's recommended number of running hours or calendar time before an aircraft engine or other component requires overhaul. On rotorcraft, many components have recommended or ma ...

s is 1000 hours, although this is expected to be increased as experience is gained. Producing at 6,200 rpm for three minutes for take-off and at 5,800 rpm continuously, the 700E was designed as a fuel efficient four stroke alternative to the high fuel consumption two stroke engines, such as the

Rotax 582 The Rotax 582 is a two-stroke, two-cylinder, rotary intake valve, oil-in-fuel or oil injection pump, liquid-cooled, gear reduction-drive aircraft engine manufactured by BRP-Rotax GmbH & Co. KG. It is for use in non-certified aircraft operating ...

. HKS 700E engines from serial number 101105 and above meet ASTM standard 2339-05, which governs the design and manufacture of reciprocating engines for light-sport aircraft. Compliance with the ASTM standard means the aircraft is applicable for use on special or experimental light-sport aircraft (S-LSA or E-LSA).HKS Engines
Compliance Statement July,2006 The company's owner's manual disclaimer states:

Variants

;700E :Initial version, normally aspirated and producing at 6200 rpm for three minutes for take-off and at 5800 rpm continuously. ;700T : Turbocharged version with a stroke and a compression ratio of 8.8:1, that produces at 5300 rpm for three minutes for take-off and at 4900 rpm continuously. The engine's dry weight is equipped with electrical system, electric starter, fuel injectors, gearbox, exhaust system and turbocharger. The initial time between overhauls is recommended as 500 hours, but this is expected to rise with operational experience.

Applications

Specifications (700E)

References

External links