A California  man blames his motorcycle seat for a painful erection he said lasted nearly two years.

Henry Wolf, 52, is now suing BMW of North America,  the motorcycle's manufacturer, and Corbin-Pacific, the maker of the seat, for lost wages, medical expenses and emotional distress.

According to his attorney, Vernon Bradley, Wolf took a four-hour ride - two hours each way - on his 1993 motorcycle on May 1, 2010.  After the trip, he developed priapism, a prolonged, unwanted, persistent and painful erection of the penis that for Wolf has  lasted 24 hours a day since the ride.

"It's very embarrassing, and all kind of problems developed," Bradley told ABC News.  "He had to reconfigure his clothing, and going to the bathroom was  a problem."

And recently things have gotten worse, Bradley said.  Wolf is now unable to have an erection.

Wolf consulted a number of physicians, who told him the condition was the result of both the configuration of the seat and the long motorcycle ride.

Dr. Ramgopal Satyanarayana, associate professor of urology at the University of Miami's Miller School of Medicine, said that while he isn't involved in Wolf's case, he has never heard of a case of priapism caused by a motorcycle seat.

Priapism, he said, can be a side effect of certain medications, such as Viagra, Cialis and antipsychotics.  It can also develop as a complication of sickle cell anemia, a disease that causes red blood cells to take on an abnormal shape.  In rare cases, Satyanarayana said, priapism could be the result of trauma.

If not treated early, Satyanarayana said, priapism could lead to permanent erectile dysfunction.

"For treatment, we tell them to take pseudoephedrine, and if that doesn't bring it down, we actually inject medications that can arrest the amount of blood coming in.  If that doesn't work, we have to operatively reduce it."

Wolf's doctors tried the more conservative treatments, his attorney said, and told him the only other option was surgery.

"If that surgery is not successful, he will never be able to get an erection with a pump or anything else," Bradley said.

Bradley plans to serve the lawsuits this week, and the companies have 30 days to respond.  He is seeking an unspecified amount of damages.