Thor 250 – Thor 250 DS

POLINI THOR 250


Polini THOR 250 engine features a liquid cooling system, that grants an extraordinary steady power output and better performance at every rpm.
Thor 250 engine is small and very compact with a great power/weigh ratio.

The die cast light-alloy aluminium cylinder grants a better thermal stability. The liner with Nickel-Siliceous coating improves the piston sliding, its resistance to wear and abrasion. The piston, gravity cast at high silicon content light alloy, reduces thermal expansion and the coupling slack. The piston top design is specific to optimize the compression ratio. The advanced technology and the great performance of the new THOR 250 gives a better feeling when driving making the flight even more performing, dynamic, reactive, beside granting more stability. THOR 250 is provided with a balancing countershaft; this feature cancels the vibrations and guarantees such a driving comfort never felt during a flight and a better engine lasting.
Polini Motori deeply directed its attention to the security matter too. THOR 250 is in fact provided with a centrifugal clutch entirely in oil bath, with a mechanical gear with helical teeth. The counter revolving rollers considerably decrease the upsetting torque-steer for a further flight comfort.
The hand starter is easier thanks to the flash starter device, which speeds up and simplifies the movements. THOR 250 engine distinguishes itself for many other advanced solutions, as, for example, the comfortable closed circuit system for the fuel recovery during transportation and the 12V output for any eventual electrical use. A version with electric starter is also available as optional. The engine has already confirmed its extraordinary performance features during the tests made on the test benches by the engineers of Polini Motori.

Polini Engine 2 stroke monocylinder
Cooling Liquid cooled
Bore for stroke 72 x 60
Displacement 244 cm3
Power 36 HP at 7500 R.P.M.
Cylinder Aluminum with Gilnisil coating
Compression ratio 11,5:1
Piston Two chromium plated rings mm 1
Intake Reed valve in the crankcase
Carburetor Ø28 Bowl
Air filter Air box
Ignition Electronic with battery charger possible
Battery charger prearrangement Output power 80 W at 5500 RPM
Spark plug hood 5k Ω resistance
Fuel type Lead free petrol with 2% synthetic oil
Gear reduction unit Helical teeth in oil bath with 2,8 reduction ratio
Starting Pull start with self winding rope Flash Starter – Electric starter (optional)
Clutch Centrifugal in oil bath
Muffler Expansion with oval silencer
Engine weight 18 Kg (19kg with electric starter) without radiator
Propeller rotation Clockwise

THOR 250 engine adapts itself to various application types, as two-seat trikes, powered hang gliders, one-seat small three-axis, ULM motor-gliders, ULM.

  • 928.000.014 – Ø 28 Carburetor – Flash starter – Euro 2.920,00 + VAT
  • 928.000.015 – Ø 28 Carburetor – Electric starter+ Flash starter–Euro 3.220,00+VAT

100% MADE IN ITALY

EXPLODED VIEW

POLINI THOR 250 DUAL SPARK


Polini THOR 250 DUAL SPARK engine features 2 spark plugs and 2 independent ignitions to grant the maximum safety standard in every condition of flight. The liquid cooling system grants an extraordinary steady power output and better performance at every rpm.

Many are the advanced technical solutions adopted.

  • The die cast light-alloy aluminium cylinder grants a better thermal stability.
  • The piston, gravity cast at high silicon content light alloy, reduces thermal expansion and the coupling slack. The piston top design is specific to optimize the compression ratio.
  • It is provided with a balancing countershaft; this feature cancels the vibrations and guarantees such a comfort when driving never felt during a flight and a better engine lasting. The counter revolving rollers considerably decrease the upsetting torque-steer for a further flight comfort.
  • The centrifugal clutch is entirely in oil bath, with a mechanical gear with helical teeth.
  • The electric starter is standard but for higher safety level it is also equipped with manual starter, with easy-system thanks to the flash starter device, which speeds up and simplifies the movements.
  • The comfortable closed circuit system for the fuel recovery during transportation and the 12V output for any eventual electrical use.

Thor 250 DUAL SPARK engine is small and very compact with a great power/weigh ratio. The advanced technology and the great performance of this engine gives a better feeling when driving making the flight even more performing, dynamic, reactive, beside granting more stability.

Polini Engine 2 stroke monocylinder
Cooling Liquid cooled
Bore for stroke 72 x 60
Displacement 244 cm3
Power 36,5 HP at 7500 R.P.M.
Cylinder Aluminum with Gilnisil coating
Compression ratio 11,5:1
Piston Two chromium plated rings mm 1
Intake Reed valve in the crankcase
Carburetor Ø28 float
Air filter Air box
Ignition 1 Electronic
Ignition 2 Electronic battery powered
Battery charger Output power 80 W at 5500 RPM
Spark plug hood 5k Ω resistance
Fuel type Lead free petrol with 2% synthetic oil
Gear reduction unit Helical teeth in oil bath with 2,8 reduction ratio
Starting Electric starter + pull start with self winding rope Flash Starter
Clutch Centrifugal in oil bath
Muffler Expansion with oval silencer
Engine weight 18,5 Kg (19,5 kg with electric starter) without radiator
Propeller rotation Clockwise

THOR 250 DUAL SPARK engine adapts itself to various application types, as two-seat trikes, powered hang gliders, one-seat small three-axis, ULM motor-gliders, ULM.

  • 928.000.019 – Euro 3.690 +IVA

100% MADE IN ITALY

EXPLODED VIEW