A century-old motorcycle numberplate worth up to $1 million has sparked a turf war among investors and superannuation funds as it goes on public sale for the first time in 80 years.

The historic NSW motorcycle number plate “1” is expected to net its anonymous owner between $500,000 and $1 million.

“It is without a doubt the most valuable, impressive and sought-after motorcycle plate in Australia,” numberplates.com.au director Steven Hantos said.

The single-digit plate has rarely changed hands and has gone on public sale even fewer times.

First owned by penny farthing dealers and Honda motorcycle importers Bennett and Wood in 1918, it was sold to Honda’s general manager in 1935.

It was then transferred in 1978 to a family in the NSW Southern Highlands region, who was attached to an Italian-built MV Agusta Motorcycle, before ending up in the hands of the current, secret owner.

The market for historic plates has grown in the past decade with the oldest, single-digit plates returning the highest return for investors.

The NSW “4” car plate set an Australian record when it was sold at auction for $2.45 million in 2017.

-AAP