I would call Public Works and get them to sweep that turn NOW if that is the problem, that's their job after all. If that won't fix it, a mirror for you and a dinotte tail light and a flag stick would be my solution. You have to make yourself look bigger. I sometimes borrow a small tractor from a neighbor up the road. When I use the tractor on the road, I am mostly driving on the shoulder with one tire just riding on the white fog line. Cars always wait to pass the tractor even though there is plenty of room- far more room than when I am bicycling the same road but cars always pass dangerously when I am bicycling that road. Now I have started taking the entire lane with my bicycle and that is working also. Look BIG.