John Kingan, aged 60, from Priory Road, Nether Edge, said he is 'absolutely gutted' over the theft of his scooter from outside his home.
The thief responsible used bolt cutters to release the scooter from a security chain anchoring the bike to the ground in the courtyard to the rear of John's flat.
John, who bought the scooter in 1979, said it is a rare model built in Italy when they were in production for just three years between 1969 and 1971.
There are not believed to be many in existence in such good condition.
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The bike was used during the filming of This is England 1990 television series.
Owner John said: "I have ridden it over all the years I have had it, on scooter rallies in this country and Europe, but for the last two years it has been my main mode of transport.
"To me I wouldn't care if the Lambretta was worth £1 or £1 million, it's the sentimental value which makes it priceless for me.
"In the scootering fraternity it's renowned as a rare model and lots of people have been doing all they can to help me get it back.
"To me, I think someone knew it was there because it was in a courtyard at the rear of a property - not the kind of place that people would just wander into with bolt cutters in their hands.
"I parked it up at 5pm on Thursday, May 25 and when I went for it the next day it had gone. I'm gutted."
The scooter Lambretta GP 200 has the registration number HHD34J.
South Yorkshire Police said it is John's 'pride and joy'.
A force spokeswoman said: "The owner has recently had the scooter fully restored after it was damaged during an accident. We need your help to find the scooter as well as those responsible for taking it.
"Did you see or hear anything suspicious in the area around that time? Have you seen the scooter or been offered it for sale?"
Call South Yorkshire Police on 101 or Crimestoppers on 0800 555111.