video://www.youtube.com/watch?v=DDWqJe1dCgY
Wow, check out this funky motorcycle with 24 Chainsaw engines. Although this thing is not fuel-efficient nor powerful, it would be an honor for anyone to drive the god-lovin’ thing while the sounds of 24 chainsaws scare off any by-standers.
The combined power of 24 DOLMAR chainsaw engines is fed into to a 5-speed Harley-Davidson transmission by a series of twelve toothed belts.
The engine in question is the one used in the PS-7900 professional chainsaw, which currently boasts the best power-to-weight ratio of any professional petrol chainsaw in the world – just 1 kg per PS. In standard trim each of these high-performance air-cooled 79 cc units generates 4.6 kW of power (6.3 PS) at 9500 rpm. A specific output of 59 kW per litre is outstanding for a chainsaw, and the secret lies in DOLMAR’s High Performance Combustion (HPC) technology. This term refers to the special design of the six gas exchange ports in combination with the asymmetrical combustion chamber head and the crankcase configuration: the result is a highly efficient combustion cycle with low exhaust emissions.
For use in the Dolmette the engines were tuned and tweaked to deliver 5.2 kW of power (7.1 PS) at 10,000 rpm. Maximum torque delivery is 5.5 Nm at 7,750 rpm. When all 24 are combined, the result is a 24-cylinder power plant with a total displacement of 1.9 litres, a power output of 125 kW (170 PS) and 130 Nm of torque at the centrifugal clutches.
