It is best to not ride directly alongside another vehicle because:
It is dangerous to ride directly alongside a vehicle in another lane because you may be in the vehicle's blind spot and the driver will have no way of knowing you are there. It can also be dangerous because the vehicle may block your path of escape if another hazard arises.
- You may be riding in its blind spot.
- It is distracting to have a vehicle next to you.
- Other drivers may want to use the lane.
- It would be difficult to see what is happening behind you.