Classic insurers say owners have unwittingly kept their cars’ agreed values at the same levels for years, despite recent price surges, particularly for 1970s and ’80s models.

Marcus Atkinson, marketing director at classic car insurer Hagerty, said the majority of classic cars are under-insured simply because owners are unaware of how much their cars have increased in value after recent price rises.

New Top Gear presenter, Chris Evans, is selling off £11million worth of classic cars at auction next month. Evans, who is replacing Jeremy Clarkson as the new presenter for the BBC show, has consigned 13 cars to the Bonhams Goodwood Revival Sale including Chitty Chitty Bang Bang.

The items include the rare right-hand drive 1966 Ferrari 275 GTB/6C Alloy, with an estimate of £2.6-2.9m, the 1971 Ferrari 365 GTS/4 ‘Daytona’ Spider,