Aixro XR 50 Specs
The XR 50 is a 4-stroke Wankel rotary engine. This ultra high performance engine produces an incredible 48hp and has such a high flat torque curve that the traditional heavy gearbox is not necessary. The engine is designed to have service interval similar to that of a traditional four stroke which keeps you out on the track and greatly reduces operating costs. More powerful, lighter weight, cleaner operating, smoother running, and cheaper to maintain.
Specification: Type 4-stroke 1-disc rotary engine
Power: 48 hp / 8500 rpm
Weight: ~ 30 lbs
Torque: 34 lbs/ft at 4500 1/min
Chamber volume: 294 cc
Max. engine speed: 10.300 1/min
Clutch: 2-disc centrifugal
Drive: 1/2 " chain type 428
Ignition: magnet ignition with variable timing
Housing: water cooled, partially Nicasil coated
Housing end plates: water cooled, special alloy
Function of the rotary engine
The XR 50 is a 4-stroke rotary engine working on the Wankel principle and consequently has no oscillating masses due to an eccentric shaft and rotor turning at 1/3 shaft speed.
During each full rotation of the shaft one of three chambers is ignited.
As all the moving mass is balanced, this type of engine layout is free from vibration, extremely powerful, compact in size and produces low emissions.
Today's rotary engines are capable of highest run performance. Therefore they are predominantly used in small, sometimes unmanned aircrafts.
The engine's main components are typically the following:
• Water-cooled housing, often called trochoid due to its inner shape.
• Rotor with seals (equivalent to a piston with ring)
• Eccentric shaft (equivalent to the crankshaft)
• End plates, which close the sides of the engine and support the shaft
The XR 50 is a carburetor engine with mixture lubrication at a ratio of 50:1, but unlike in 2-stroke engines all oil is combusted without residue.
Fresh gases initially flow through one end plate, stream through the rotor, bearings and shaft cooling and lubricating, before passing into the combustion chamber through the opposite end plate.
At ~5500rpm a negative-pressure controlled butterfly valve opens a second port feeding additional gases directly into the combustion chamber.
These cold gases give rise to the enormous power of the XR 50. The untypical processes in the engine result in very long control times that positively influence exhaust gas values, which are typically under 1% of comparable 2-stroke units and equal to the best 4-stroke levels.