We’ve heard it said before, but has the death of the two-stroke been exaggerated? For road bikes perhaps, but Italian engine maker Motori Minarelli still thinks there is life in the stroker, at least for enduro machines – it has unveiled a new engine which it says meets Euro 5 emissions standards (Euro 5 is the fifth iteration of European emissions limits that have got steadily stricter since the original Euro1 came in 1999.)

The company showed the new single-cylinder 300cc engine at the EICMA show in Milan. Said to be based on Yamaha’s YZ250 power unit, which is designed for enduro use, Minarelli’s version has been designed in-house and features electronic fuel injection and electric start. The University of Modena was involved in the design stage, undertaking fluid-thermodynamic research. Other features include an exhaust valve to improve low and mid-range performance, as well as an automatic decompressor which helps the bike to restart quickly if it stalls.
According to the maker, the 300cc unit has got beyond the prototype stage and has already been given to a few Fantic factory riders. Minarelli already supplies engines to Fantic, and the new XE300 trials bike, due for launch in 2023, will be the first production motorcycle powered by the new unit. As it meets Euro 5 standards, the engine could conceivably be used in a road bike as well, though there’s no indication of this at present.

BMF Chair Jim Freeman said: “Standards are standards, if a stroker meets them, what’s the problem? The days of ‘stink wheels’ are long gone, along with premix and the Villiers 2T. Sounds like an interesting power to weight ratio, if it’s designed for enduro use.”

Written by Peter Henshaw

Top image courtesy of Motori Minarelli