Titan ZG 62SL

The Titan ZG 62 was first produced in 1985 being designed so as to fit into a chain saw and at the same time being able to be used for model purposes without modification. The sales volume with the ZG 38 for models made this possible.

In 1990 Komatsu reworked the cylinder specially for model aircraft purposes this S cylinder had the transfer passages altered as well as the combustion chamber. This resulted in an increase of 200 rpm in the 6,500 range. Fit a tuned pipe and the rpm is considerably increased, giving a power of 6,6 hp at 8,400 rpm.

The newest Titan, the 62SL, has a diecast aluminium crankcase weighing 50 grams less than the previous sand cast version.

Many people still believe that chain saw engines are too heavy for models, that these motors run too roughly. This is to ignore the fact that such firms as Zenoah have been very active to stay competitive in a very hard market. These chain saw companies, to remain competitive, must continually invest very large sums of money in research and development to improve their engines, making them as light as possible, smooth running and powerful. The cost for such development requires huge sums of money, these large development costs are only possible due to the high volume of sales of chain saws.

Model engine manufacturers cannot sustain such enormous development costs. Another very important point is, the chain saw customer has exactly the same requirements of his chain saw as does the modeller of his model airplane engine. These are: light weight, minimum of vibration, power, reliability, minimum maintenance and more recently low noise levels. With the Titan ZG 62SL these requirements are arrived at by an unusual route.

The 62 has a very short stroke, this has two advantages, first the motor is smaller thereby, and second the piston acceleration is not so high reducing vibration, a birds beak opening in the top side of the exhaust port causes a slight reduction in power, but serves to reduce the noise by preventing the exhaust port suddenly opening in the full width as the piston is descending, this reduces the sharp pressure wave fluctuations. The latest die casting technique are employed to produce very wide but very thin cooling fins and the flywheel is unbelievably small and with the very light electronic ignition system, the ZG 62 is with a wide margin the lightest petrol engine in it’s class.

The crankshaft is a hefty piece of forged steel, induction hardened, with a diameter of 15 mm and supported in two large ballraces, the conrod is a forged unit also induction hardened with caged roller bearings both ends, the gudgeon pin is hollow. There are two thin pegged rings. The ignition unit consists of two separate coils, both fixed to the side of the motor causing no interference with the cooling air. The standard Walbro pump carburettor is fitted with a choke.

The very wide and cleanly formed cooling fins allow the use of large propellers causing the motor to turn at relatively low speeds. For aerobatic aircraft like our CAP 21 the 22×10″ or the 22×12″ Menz S propeller has proved to be very good. Our big Tiger flies best with the 24×10″. If you wish to, or must, reduce the noise still further, then you can pull the intake air out of the fuselage by fitting a 90 degree bend between the carburettor and motor. The intake noise is louder than the noise from the standard silencer. This bend by lengthening the intake tract allows the fitting of a 24×12″ or 26×10″ Menz S propeller, of course you are not going to get the maximum power from the motor by this method, but you have more than enough power to fly our big Tiger with the 62’s throttle set at just a rather fast tickover.

The lowest possible noise level in flight with lots of power is obtained with our Hydro-Mount-System, coupled with the Stainless steel silencer, sucking the intake air out of the fuselage and fitting a Super Silence 21×12″ Carbon 3-blade propeller at 6,300 rpm. For higest performance use the Super Silence 24×10″ Carbon 2-blade prop. It produces 130 N static thrust at 6500 rpm.