The incident happened between 5.35am and 5.50am on Tuesday, 24 November.
The victim, a 58-year-old man, was cycling on Otterbourne Road when he was approached by two men on a moped who told him to get off of his bike.
They then assaulted him, causing him to fall to the ground. The two suspects then made off with the bike.
Police have conducted a number of enquiries and are now turning to the public for help.
Were you in the area at the time? Perhaps you drove past and have dash cam footage that could assist the investigation?
The victim attempted to flag down a bus and a car but was unsuccessful, we would be particularly keen to hear from the drivers of those vehicles.
Anyone with information can phone 101 with reference 44200454313.