A motorbike bought in instalments through a gentleman's agreement is set to sell for five hundred times what it cost.
Guy Chambers took over his friend's unwanted 1930 Brough Superior in the 1970s, but with a young family to support, didn't have the £200 that was being asked. Instead, he agreed to pay off the debt at £5 per month.
Mr Chambers had several years happy biking until a conrod broke in 1976, taking the bike off the road for fifteen years. It was revived in 1991, and has been used regularly ever since.
But as interest in vintage British motorbikes has rocketed over the last 40 years, so has the value of the bike - and it's now expected to go for as much as £100,000 when it goes under the hammer next week.
"Legendary superbike of motorcycling's between-the-wars 'Golden Age', the Brough Superior was synonymous with high performance, engineering excellence and quality of finish," says auctioneer Bonhams.
"The 1930 Brough Superior OHV 680 Black Alpine offers unparalleled levels of originality, a beautiful patina and a traceable ownership history."
The bike was originally supplied in August 1930 by Laytons of Oxford to one DR Venables, who took it to Switzerland and the south of France the following summer.
In late 1931, it was sold to Chris Arthurs, a skilled carpenter who lived in Reading. He fitted a sidecar, so he could use it for work and family holidays, and added distinctive discs to the wheels. And after having offered first refusal to Mr Chambers years earlier, he finally sold it on the instalment plan in 1971.
The bike has had its fair share of attention in recent years. In 1996 it featured in 'The Big Breakfast' on Channel 4 - along with Wallace & Grommit. In the 2014 Banbury Run it won the prize for the best Brough Superior and was the only Brough to be ridden to a Gold Award. It's in very good nick, says Bonhams.
Along with the Brough, there are a number of other British and American bikes in the auction - including a dozen being sold by former Top Gear duo James May and Richard Hammond.
"Just because I'm unemployed now doesn't mean I have to get rid of everything. I was going to sell these bikes anyway," says May. "And those paintings, and my collection of Scalextric cars. Honest."
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