In 1939 Mamod introduced the Minor 1 and 2. The single cylinder Minor 1 (aka MM1) became one of their most popular models but the twin cylinder Minor 2 (MM2) was a commercial failure, with only 100 being made. A larger version of the MM1 was later introduced and named Minor 2 (MM2) which became as popular as the MM1, but the original twin is now a rare and much sought after collector's item.
In 2007, Ian Grantham made a replica of the original MM2 twin. He decided to make it a limited edition of 100, to match the 100 made by Mamod. The engines are made in small batches and this is #56, made (I believe) in 2011 (despite the label, which states 2007).
It is pretty close to the original, but, if anything, better quality. It is basically the same as the MM1 but with 2 horizontally opposed cylinders. The boiler is 1 1/2" diameter x 4 1/4". It has a dummy chimney, safety valve and, fixed to the top under the copper boiler band, a bracket for the twin cylinders. The bracket is engraved with the name MF Twin and the serial number 056.
The cylinders are 1/4" diameter x 1/2" stroke. The two inlet ports are fed directly by short pipes, soldered directly in the boiler top. The simple crankshaft has a disk crank at one end and a small pulley on the other.
The base is the same size as the MM1; 4 1/2" x 2 1/2". My example has a single wick meths burner. MF can supply an optional 2 wick burner, as per the Mamod original.