In 1954 due to demand from the public, for a larger engine, the Model D150 was announced with a 148cc engine. The overall top speed was improved slightly but the main area of improvement was in torque and gear ratios to make the ride smoother and to help the scooter make it up mountain passes.
The 150D came only came in 2 colours Sand beige 8029 and a few examples from 1956 came in Light grey 8012. Engine and frame were once again painted in Aluminium Fiat 690.