
Quoting
Mr. Knowitall
If you are riding down a road at a reasonable speed for the roadway, there are no indications of road work or stopped vehicles ahead, come around a blind curve, and run into the back of a maintenance vehicle that is blocking the bicycle lane, you have an argument that the company that placed its vehicle in that location was negligent.
If you are riding down a straight road, a vehicle is parked on the road ahead of you, but you fail to look up and notice its presence until it is too late to avoid colliding with the rear of the vehicle, even if it would have been safer for the owner of the vehicle (or its workers) to post warning signs in advance of the vehicle, it becomes very difficult to prove negligence on their part because all you had to do to avoid the accident was pay a reasonable amount of attention to the road ahead of you.
Also, as a matter of routine, people operating bicycles and other vehicles on roadways will encounter emergency vehicles that partially block the road without any advance notice -- utility vehicles, tow trucks, ambulances, police vehicles and the like. It sounds like the vehicle that you encountered had a clear, illuminated arrow sign warning you of its presence and which way to divert your bicycle to avoid collision. It is very difficult to argue that such a sign is an insufficient warning if all you had to do was look forward down the road and see it, and you had a reasonable opportunity to do so before hitting the vehicle.