British Cycling and Welcome to Yorkshire say proposals to ban cyclists from a stretch of the A63 are "deeply concerning."
Highways England is consulting on a ban between North Cave and the Daltry Street Interchange, which is used in summer for time-trial events attended by riders from all over the country.
The two organisations have jointly objected to the ban which they say could impact on the local economy and set an "extremely dangerous" precedent, which could lead to cyclists being banned from most roads.
British Cycling CEO, Julie Harrington, and Welcome to Yorkshire chief executive Gary Verity said: “Any ban imposed on cyclists would have a negative impact on the local economy, as well as people’s ability to participate in the sport ahead of a potentially hugely significant year as Yorkshire looks forward to hosting the 2019 UCI Road World Championships.”
Mr Verity added: “After the success of hosting the Grand Depart of the Tour de France in 2014 and the subsequent annual editions of the new hugely popular Tour de Yorkshire, the county is rightly renowned as the ‘Cycling Capital of Europe’ and the negative impact of this decision will undoubtedly impact that reputation locally, nationally and worldwide.”
Highways England, which proposed the ban, said "in the interests of road safety" cycling should be banned after six accidents involving cyclists – including one fatality – in the last five years.
Humberside Police has had concerns about using the route for time trials for some time and also do not believe it is “safe and appropriate”.
Christopher Auker, 65, died in a Good Friday time trial in 2013, when he crashed into the back of a stationary caravan which had a tyre blowout.
At the time his widow described it as a “freak” accident, saying they both felt a dual carriageway was safer for racing as drivers had room to overtake.
Ms Harrington and Mr Verity said the accidents had to be put into context with nearly 300 collisions involving motor vehicles on the same stretch of road over the same period of time.
The public consultation is open until February 19.