Price & Availability
Parts List Owners Guide

The HB .61 is a renowned engine for durability and performance. It was used by the US Army to power target drones in the 1980's. Its light weight and high power make it a favorite for many modelers. The patented PDP ports boost the power without increasing fuel consumption. These 4 finger ports are located on the exhaust side of the baffle and introduce an additional fuel charge in a normally dead area of a loop scavenged engine design.

SPECIFICATIONS	HB .61	HB .61 PDP
Horsepower *	1.45 @ 16,000 RPM	1.85 @ 16,000 RPM
Practical RPM *	1800 ~ 16,000	1800 ~ 19,000
Porting Arrangement	Loop Scavenged	Loop Scavenged with PDP ports
Bore & Stroke	.945" (24mm) Ø x .866" (22mm)
Prop Shaft Thread	1/4 x 28
Piston/cylinder type	Dykes ring piston / hardened steel liner
Connecting Rod	Forged Aluminum bushed at both ends
Crankshaft	One piece hardened Steel
Displacement	.61 cu. in. (9.97 ccm)
Engine Weight	14.6 oz. (413 gr.)
Muffler Weight	4.2 oz. (119 gr.)
Bearings	Double Ball Bearing supported crankshaft
Carburetor	O-ring sealed twin needle with full fuel metering, composite body.
Carburetor neck Dia	.530" (13.5mm) Ø
Carburetor Throat	.312" (8mm) Ø

*Specification's subject to change depending on fuel, prop, exhaust system, etc.