The Valach VM 70S1-4T has the same well proven Nickel-Silicon plated cylinder and the cylinder head as the VM 60S1-4T, sitting 2.5 mm higher on the crankcase. The 5 mm longer stroke of the crankshaft increases the displacement to 70cc. It weighs only 60 g more than the VM 60S1-4T.
Valach Motors
VM 70 S1-4T
- Very light, weighs 2 lb less than other 4-stokes in it’s class
- Swings big propellers with high efficiency in an reasonable RPM range
- Exceptionally pleasing sound caused by big Honda valves and clever valve timing
- Spontaneous throttle response and smooth mid-range transition
- Small frontal section with the valve train, carburetor and exhaust behind the cylinder
- Nickel-Silicon plated cylinder surfaces
- Completely enclosed valve train
- Only one camshaft
- Three crank bearings
- Valach microprocessor controlled ignition with auto advance and retard
- Ignition is designed for a 2s LiPo battery
- VM-Motors are designed using the latest tools and techniques
- Rapid spares delivery and repair service from Germany by Toni Clark practical scale GmbH
The VM 70S1-4T is also available with a starter. With the current version of the VM 70S1-4T the starter can be retrofitted anytime.
The VM 70S1-4T is 1 kg lighter than other four-strokes in it`s class because of only one camshaft, nickel-silicon cylinder lining and a CNC milled crankcase. Anyway it is a robust engine with M5 crankcase and cylinder base screws.
The carburettor is placed behind the engine, resulting in an very narrow engine which fits into nearly every cowling. Being a four stroke with a large capacity produces a very realistic full-size aircraft sound. With a relatively small silencer the sound level is very low rather like a small saloon car.
The Valach VM 70S1-4T is a four stroke OHV engine with two valves per cylinder, running on petrol/oil mixture. Valves and their seats are manufactured by Honda, ensuring a very high quality. The fully encapsulated valve train reduces sound as well as ensuring the rocker arms are well lubricated.
The Fiala propellers are very efficient, this being due to minimal blade thickness. They sound especially good on four stroke engines. Ideal Fiala two blade propeller sizes for the VM 70 are 24×14″, 26×10″ and 26×12″. For aerobatics and glider towing the 24X12″ is ideal. For our big Tiger Moth the 26×10″ is the best choice.
The fuel consumption is approximately 50% compared to that of a two-stroke engine with the same displacement. A 300cc fuel tank lasts for about 15-20 minutes of flying time.
In Germany we recommend Aral Ultimate 102, as the smell is not so penetrating, it can be stored without deteriorating and it does not contain ethanol! If in your country petrol does not contain any ethanol, you can use any brand you like.
Specification | |
Capacity | 70 cc |
Bore | 47 mm |
Stroke | 40 mm |
RPM range | 1000-6200 1/min |
Hight from crankshaft CL | 157.5 mm |
Length from engine mount to prop hub | 174 mm |
Weight including prop bolts and carb intake trumpet | 2,300 g with Starter 2,780 g |
Weight including prop bolts, carb intake trumpet and ignition | 2,420 g with Starter 2,900 g |
Ignition voltage range | 4.8 - 9 V |
Fiala Prop 2-blade | 24x14" |
Fiala Prop 3-blade | 22x14" |
Fuel | 1:30 - 1:40 |
Fuel: Valvoline SynPower 2T / Aral Ultimate 102 | |
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In our webshop you will find all our airplane kits, engines, accessories and more. If you have any questions, please don’t hesitate to contact us!