It happened in Wetherby Road on Saturday evening when the male driver of a silver Honda Civic became aggressive towards the motorcycle rider.
A North Yorkshire Police spokesman said: "We are appealing in particular to a member of public who witnessed the incident and stopped to assist the Deliveroo rider – a 23-year-old man – who, although not physically injured, was very shaken up by the incident."
Officers also want to hear from any further witnesses who remember seeing the two vehicles on Wetherby Road at about 6.50pm or who witnessed the altercation.
Email email [email protected] or phone 101, select option 2, and ask for Sheree Evans.
Callers are asked to quote the reference number 12170107508 when passing on information.