Avon & Somerset Police are appealing for spectators with video or photos of the fatal accident to contact them.
The crash happened as 23-year-old cyclist Junior Heffernan came round a bend during the Severn Bridge Road Race.
Here is Acting Inspector Darren Jarvis...
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Bristol's goes baa-rmy as this summer's Shaun in the City trail kicks off. Plan your quest to find all 70 Shauns with this taster guide.
We've been getting acquainted with the Shaun the Sheep sculptures heading out on location for this summer's trail across Bristol
The Shaun in the City sculpture trail, which hits Bristol's streets on Monday, was given its official, and typically unusual, launch today.