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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A photographic exhibition celebrating the people that keep Bristol running overnight has opened at the Harbourside Arts Centre.
It's another mild and grey day with some rain around Gloucestershire and Bristol.
It's looking cloudy and grey into tomorrow morning with some heavier rain in Gloucestershire and Bristol.