The incident happened at around 5pm on Sunday, July 12, when 57-year old Patrick Ross Williams, from Dockenfield, was involved in a collision during which he sustained life-threatening head injuries.
Mr Williams was rushed to St George’s Hospital in Tooting, London, but died from his injuries two days later.
Investigating officer Sergeant Julian Williams is appealing for anyone who may have seen Mr Williams on his bike that day to get in touch.
Police are particularly interested to hear from the driver of a lime green vehicle, possibly a Ford, which was not involved in the accident but may have vital information.
Anyone with information should call Hampshire Police on 101, quoting Operation Local.