Four drivers could help piece together how a 51-year-old motorcyclist died when his bike hit the crash barrier on the A20 at Wrotham Heath.
All four vehicles are believed to be in the area at around 3.45pm on August 28 when the bike rider, from Surrey, died in a crash on his red Honda Fireblade.
Key footage from the scene of the crash identified the fact the vehicles had negotiated a roundabout at the junction with Pilgrims Way and London Road and were travelled down Wrotham Hill just before the accident.
It's believed the biker came off his motorcycle near the vehicles.
The drivers are asked to call the serious collision investigation unit witness appeal number on 01622 798538, or email@example.com, quoting DM/152/14.