A unique 1951 Vincent White Shadow Series C in Chinese red is expected to make $300,000-350,000 in a classic motorbikes sale at Bonhams Las Vegas on January 7.
Vincent manufactured only 1,507 Series Cs. Of these, around 15 are thought to have been rare "White Shadow" variants of the Black Shadow, sold with unpainted bodywork.
The present lot is thought to be the only red-painted specimen ever offered for general sale. The colour was used on the company's team racing models.
The Black Shadow was one of the fastest motorbikes of its era and had a strong reputation for quality.
Comedian, talk show host, and classic machines lover Jay Leno explains the appeal of the Series C. "There's a wonderful 'mechanical-ness' to them; they are such quality machines," he says.
"When you check the oil in a Vincent primary case, there's a beautiful aluminum knurled knob on the dipstick. It's overdesigned, way better than it needs to be.
"The general public ignored this kind of detailing because they could buy something cheaper. But today, the Vincent is considered a piece of art to be revered."
A Harley Davidson XL1000 from the movie Viva Knievel (1976) - starring stunt rider Evel Knievel - is valued at $80,000-100,000.
It has recently been repainted by George Sedlak, who painted all of Knievel's original jumpbikes.
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