Minarelli AM6 engine - everything you need to know

For more than 15 years, Minarelli's AM6 engine has been installed on motorcycles from brands such as Honda, Yamaha, Beta, Sherco and Fantic. It is by far one of the most used 50cc units in automotive history - there are at least a dozen variants of it. We present the most important information about AM6.

Basic information about AM6

The AM6 engine is manufactured by the Italian company Minarelli, part of the Fantic Motor Group. The tradition of the company is extremely old - the production of the first components began in 1951 in Bologna. In the beginning, these were motorcycles, and in subsequent years, only two-stroke units.

It is worth explaining what the AM6 abbreviation refers to - the name is another term after the previous AM3 / AM4 and AM5 units. The number added to the abbreviation is directly related to the number of gears of the product. 

AM6 engine - technical data

The AM6 engine is a liquid-cooled, single-cylinder, two-stroke (2T) vertical unit. The initial diameter of the cylinder is 40,3 mm, the piston stroke is 39 mm. On the other hand, the displacement is 49,7 cm³ with a compression ratio of 12:1 or higher, depending on which brand of car is equipped with an engine in this category. The AM6 engine was also equipped with a starting system, including snacks foot or electric, which may occur simultaneously in some models of two-wheeled vehicles.

Minarelli AM6 drive structure

Italian designers paid special attention to the lubrication system, which includes an automatic or manual agitator, as well as a gas distribution system with a reed valve directly in the crankcase. The carburettor used is a Dellorto PHBN 16, however this may be a different component for some engine manufacturers.

The equipment of the AM6 engine also includes:

• cast iron heating unit with a five-stage piston;
• vehicle type approval;
• 6-speed manual transmission;
• controlled mechanical multi-plate clutch in oil bath.

Examples of motorcycle models that can use the AM6 engine are Aprilia and Rieju.

The unit from the Italian manufacturer can be used in both new and old motorcycles. This is due to the fact that there are many varieties on the market. This engine model was decided to be installed by the designers of brands such as Aprilia and Yamaha.

Aprilia RS 50 - technical data

One of them was the Aprilia RS50 motorcycle. Produced from 1991 to 2005. The power unit was a single-cylinder two-stroke AM6 engine with an aluminum cylinder block. The AM6 engine was liquid-cooled and had a displacement of 49,9 cm³.

Aprilia RS50 was produced by Derbi and was especially popular with buyers from those countries where there were restrictions associated with the dimensions of the power unit of the motorcycle at a certain age of the owner. The two-wheeled vehicle could reach a speed of 50 km/h, and in an unlimited version - 105 km/h. There are similar bikes, for example, in the Derbi GPR 50 and Yamaha TZR50.

Yamaha TZR 50 WX Specifications 

Another popular AM6 powered motorcycle was the Yamaha TZR 50 WX. She was distinguished by an athletic and dynamic figure. The motorcycle was produced from 2003 to 2013. It has double-spoke wheels and a single seat for driver and passenger. 

The displacement of the liquid-cooled unit used in this model was 49,7 cm³, and the power was 1,8 hp. at 6500 rpm with a torque of 2.87 Nm at 5500 rpm in the limited model - the unlimited maximum speed was 8000 rpm. The Yamaha TZR 50 WX can reach a top speed of 45 km/h and 80 km/h when unlocked.

Opinions about the unit from the Italian manufacturer

On the user forum of the unit, you can find out that buying a motorcycle with an AM6 engine will be a good choice. It features stable operation, optimal horsepower, and simple and inexpensive operation and maintenance. For this reason, when looking for a good motor in a store, you should pay attention to this particular unit.

A photo. homepage: Borb via Wikipedia, CC BY-SA 3.0