A cyclist left with amnesia after he slammed headfirst into a temporary street sign told police he was assaulted two weeks earlier.

Hamilton scientist Robbie Price believed the injuries suffered in the attack may have contributed to the April cycle crash, which has left him without any memory of the past 10 years. When police asked Price after the crash if he wanted to go ahead with his complaint, he could not remember the attack.

His wife, Roshni Kanta, said his doctors thought the attack had contributed to the seriousness of his later injury. Her husband told her he was cycling beside the Waikato River when he was attacked by a dog and its owner knocked him off his bike when he pushed the dog away. He had complained of only a sore knee and did not seek medical treatment.