Wiltshire councillor for Malmesbury Without, Bernard Ingham, said the road, which has a 60mph speed limit between Corston and Malmesbury, is treacherous.
He said: “It can be pretty dicey coming out of the Grange Lane junction because traffic comes up pretty fast from the south.
“The problem is the road isn’t wide enough. “If you have two lorries passing each other you can hardly slip a piece of paper between them. If that happens when a cyclist is there then they would be taken out.”