44 mm


38 mm

RPM range

600 - 7000

Height from prop shaft or diameter on radial and twin

11.57 inches

Length mount to hub

11.45 inches


With ignition 7800 gr

With starter 7930 gr

Prop range 2 blade

30*14 - 34*12

Prop range 3 blade


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You choose

Rotational direction

Starter/ no starter

Long or short Edition

Vogelsang Aeroscale is the official and trademark protected Kolm dealer for the US market as well as Canada and is working closely with the manufacturer in order to protect your best interest as well as to offer you the best service possible based on our many years of Kolm experience and service. Constructing and manufacturing four stroke engines for scale models is Hans Kolm’s passion. Model engines designed and built by model aviators for model aviators is their line of operation. Hans Kolm looks back on nearly 40 years of flying model aircraft. In combination with the know-how of his competence center CNC Technik Kolm this creates an excellent basis for the design, development and production of reliable, innovative and long lasting engines. Unique solutions, oftentimes custom, instead of cheap mass production for the faceless masses, only four stroke gasoline engines are manufactured at Kolm Engines in Austria. The development and construction is conducted on state of the art 3D CAD systems and all parts are manufactured with CNC techniques by Kolm Engines under intense quality control.An inspection and test stand report are given characteristic of thorough quality management.

Kolm engines are high end quality machines, Design, development, prototyping, production and quality control all from one hand – Kolm Engines Austria as a full systems supplier. The highest quality and reliability is paramount and the basis for customer satisfaction. Even the electronic ignition system is made in house in order to grant total control and unhindered development. Prior to delivery all engines pass a one hour quality control run on the Kolm bench, quality control being their obligation.They are the sole manufacturer that is interested in working with you on YOUR motor. Let it be timing, rotational direction, on-board starter, length from mount to hub, install sets. Kolm keeps pushing the limits of what was thought possible, both in quality, configuration and customizability.

Dr. Vogelsang has been working with Kolm for many years now, is currently flying a Spitfire on a 2 cylinder Kolm inline with his unique cooling solution -  You see, we actually USE these engines, not just sell them. Furthermore Dr. Vogelsang is in contact with Kolm constantly, speaks with their technical staff, in order to keep up with the latest innovations and changes at Kolm and be educate himself first hand on what new developments are taking place, both when it comes to service, maintenance and new engines in development.

Götz : As all gas engines you need to keep an eye on your cooling. It is not about how much air gets in, it is important that it is forced over the cooling fins and is able to exit through ample ports. Ideal is a ratio of “cowl” intake area to exit of 1:2 or 1:3. I run basically all of my 4-stroke gas engines on our APS fuel pump, which is fully programmable. This ensures that on radial engines we are not dependent on the artificial air impulse driving the Walbro, and on all other engine layouts it eliminates the danger of the impulse line hydro-locking on the oil that wants to exit the crank case housing. As with all 4-strokes you have many possible exhaust layouts to play with. From lightweight to sophisticated, from loud and menacing to quit, from as easy as a simple straight pipe to the most complex setups. I would love to get the chance to discuss the options with you. If your install allows I would always consider an air filter. This is not mainly to keep the dust and grime out of your motor, the true effect is your carb being offered a “steady” environment, your carb running at a leaner needle setting and most of all, keeping the inside of your cowl area and airframe clean from the otherwise expelled pre-mix oil.

We carry many exhaust solutions, many accessories and upgrades and the correct propellers. Furthermore we can offer custom made, absolute museum quality, flying propellers for your top tier projects.

3-Seitenansicht-BX240_01.pdf Download: 3D view

The BX-240-4 is exactly the flat four twin that so many have waited for. It is now at last possible to build 33% to 40% scale models powered by a 4-cylinder four stroke engine.

The Kolm BX-240-4 is ideal for all models up to 35 kilos (77 lbs) in weight and with the optional electric starter leaves nothing to be desired.

•Nickel-Silicon plated cylinder surfaces, far lighter than steel cylinder liners guarantee high wear resistance

•Assembled heat-treated steel crankshaft with Tungsten balance weight inserts

•Conrods are CNC milled from high strength steel, and have a spindled bore surface for the big end needle roller bearings

•Plain bronze small end bearings

•Single camshaft acting on overhead valves by pushrods

•A light weight, low inertia valve train allows relatively high RPM

•Crankcase CNC milled from high-strength aerospace alloy

•Excellent Müller-Microprocessor-Ignition developed by Günter Müller in Germany, now made in Austria by Kolm Engines

•Valves and pistons are manufactured at Kolm Engines in Austria on modern CNC machines

•Two Walbro carburetors WT-225

•Engine length adjustable by longer and shorter optional prop hubs

•Spares delivery and repair service here in the USA

Each and every Kolm engine is tested in the factory and run for thirty minutes. Of this test a detailed proof certificate is supplied.


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