Q. I’m a motorcycle rider and have noticed over time some of the vehicle detectors at various intersections do not detect motorcycles and I end up sitting waiting and eventually proceeding through a red light. My question is, is it legal to treat the red light the same as a stop sign when it does not change because of the motorcycle, but works fine for automobiles?

A. No, it is not legal for a motorcycle to treat a red light as a stop sign if the signal does not change for a motorcycle. A vehicle should not proceed through a red light under any conditions. We do not ever recommend running a red light because it is a safety concern for the cyclist as well as other motorists and pedestrians, and it is illegal to do so.

Traffic signal sensors are made of wires buried in the asphalt in a rectangular shape, typically 6 feet wide by 40 feet long. Electricity is run through the wire and generates an electromagnetic field. When a vehicle interrupts this field, the light’s control system detects this and understands there is a vehicle waiting for the green light. These magnetic fields emanate from the wire in concentric circles, and would look like a big Slinky coiled around a wire if electromagnetic fields were visible. As such, the field strength drops off as you move away from it.

RIDOT always recommends that a motorcyclist not sit in the center of the vehicle detector, but rather place the bike to one side or the other. This should help the motorcycle to be detected. In most intersections, the perimeter of the sensor is easy to see. Cars and trucks have more surface area, and that is what helps activate the signal.

Also, we suggest that if there is a signal that is not detecting their motorcycle, drivers should call RIDOT’s Customer Service office and we will field review the particular signal. Sometimes, the sensitivity of the detector needs to be increased. Usually with the combination of the increased sensitivity, as well as the motorcyclist sitting on the far side of the detector, the signal will change for them.

Manhole covers fixed

Q. I live between West Greenville Road and Fuel Depot on a side street off of Route 44 in the western part of Greenville. At the end of Vaughn Street, my street, is a manhole cover that is sinking. When driving south on Route 44 in the far right lane, where all the covers and drainage grates are, especially when it is an 18 wheeler, our house which is a distance up on Vaughn, shakes. Our main concern is that this manhole is in danger of collapsing. Can you look into this?

A. RIDOT sent a crew out from our Glocester Maintenance Facility to inspect the manhole covers at your request. These manhole covers are made up of metal frames and covers that over time sometimes need to be reinforced.

There are five manhole utility covers in the area of West Greenville Road and the Fuel Depot in Greenville that are owned by the Smithfield Sewer Authority. The utility owners typically maintain the road surrounding their manholes but in this instance RIDOT brought the covers up to grade with the surrounding street, reducing the dip in the road. RIDOT has also contacted the Smithfield Sewer Authority so that they can make any additional repairs.

RIDOT has a Customer Service office that can be reached by calling (401) 222-2450 or on the Web at www.dot.state.ri.us should you or any other reader need any additional assistance. Their office is open from 7:30 a.m. to 4:30 p.m. Monday through Friday.

Dana Alexander Nolfe, chief public affairs officer for the state Department of Transportation, has agreed to answer questions of general interest posed by Journal readers about state roads and other state transportation matters.

The DOT is responsible for the state’s transportation infrastructure, which includes highways, bridges, traffic signals and bikeways.

To ask a question that would also be of interest to other readers, send a letter to Ask RIDOT, Features Department, The Providence Journal, 75 Fountain St., Providence, RI 02902. You can also e-mail your question to projocars@projo.com. Please put “Question for the DOT” in the subject field.

Questions or complaints of a specific nature should be posed to the DOT directly and will not be answered in this column.