The story begins in Italy, for our purposes, in 1946. Vincenti Piatti had designed a 50cc engine unit for driving portable lathes and also foresaw the possibilities of this engine power-assisting a bicycle – the Mini Motore. Italy was suffering the results of six years of war and there was a huge demand for cheap personal transport, fuel being scarce and expensive.
In 1948, George Murray Denton was holidaying in Switzerland: “…I followed a cyclist who not only free-wheeled downhill but shot uphill with no loss of speed and with only occasional pedalling. There was a device behind the saddle which emitted blue smoke and a noise like a bored-out wasp. It was an Italian Mini Motore.”
On his return to England, George found that Trojan of Croydon were making them under licence for sale in the UK. George later became Sales Manager of Trojan and reckoned that, by the time sales were overtaken by the more technically advanced Cyclemaster in 1951, over 100,000 must have been sold.
In the photo below, you can see the engine above the tyre; and also pushed down onto the tyre, ready to roll.
In England, Mini-Motors were built by Trojan Ltd. of Croydon. In France it was built at ‘Minimotor’, 35 Rue de Clichy, Paris. On its engine plate it has the number 7/52, which I assume means it was built in the 7th month of 1952. The same number is stamped on the engine itself.
The two engines have various differences. The French version also has a charming drive control unit fitted to the rear which, by means of a drive control lever on the top tube of the bicycle, raises and lowers the engine onto the tyre. You can see it in the photo below (and also in operation in the video further down the page)
1952 Moteur Auxiliaire ‘Hors-Bord de la Bicyclette’ Mini-Motor
A French-built Mini-Motor on a Semper bicycle
21″ Frame
26″ Wheels
Engine No 7/52
(Now sold)
I bought this French Mini-motor from my friend Patrick in Paris in 2008. He rebuilt the engine (it’s his photos further down the page showing the difference between the English and French engines). I then sold it to a customer.
But I discovered that unfortunately it had not been stored very well. I visited the customer recently and found that the bicycle had deteriorated. I ended up buying it back, and I am now offering it for sale again, this time as a ‘barn find’ for restoration.
The engine is sound, and turns freely with good compression. The bicycle either needs restoring or replacing. As you can see in the video, the lever mechanism also works, to pull the engine up …or down onto the tyre.
