You should speak to a criminal defense lawyer immediately. Although harassment is a summary offense, it does carry a potential jail sentence of up to 90 days and fine of up to $300. A lawyer can tell you what defense you may have to the charge, and help you resolve the matter at the MDJ office. Although you call the pavement yours. if it is a public pavement and open to vehicle traffic the individual can ride his bike on it. If the pavement is not open to the public or intended for motor vehicle traffic there may be a means to stop further intrusions onto your pavement.
Harassment requires proof of the defendant's intent to harass, annoy, or alarm another person. I don't have all the facts alleged against you or more of what your actions actually were so I don't know if this could be part of a defense. I am available to talk to you to discuss your defense. I suggest you plead not guilty and request a summary hearing.
Andrea E. Mertz, Reading, Berks County, PA.