Police have revealed that a second vehicle was involved in the smash where a motorcyclist died on the A414 in Hemel Hempstead just before 3.45pm on Saturday.
The biker, in his 20s, was overtaking an Audi 3 car when he collided with the roundabout at the Breakspear Way junction with Green Lane.
Both drivers were travelling towards the M1, but their vehicles did not touch.
Paramedics tried to resuscitate the biker at the scene, but he was pronounced dead shortly afterwards.
A comment under our previous story on the man who died reported that he leaves behind a wife who is eight months pregnant.
The police had initially said it was just his motorbike that was involved in the smash.
But spokesman Sarah Spence said: “Further to initial investigations we can now confirm that the collision on Saturday is technically a two-vehicle collision.”