This paper proposes the design of a low cost anti-theft sensor for motorcycle security based on detection of the rotation of its handlebar. An advanced motorcycle security device has also been developed on the basis of this proposed sensor. Currently, vibration sensors are used for motorcycle security purpose, which are very infuriating. In case of security device using vibration sensor, sometimes the jerking of a bike leads detection of thievery situation even though it is not the actual thievery case. But our designed sensor detects the thievery situation only when the handlebar rotates from left to right at a certain angle or vice-versa which really needs to be done to run a bike. Apart from the sensor, the overall device contains a GSM-GPRS module, micro controller, relay, buzzer, SOS button as well as other electronic components powered up by a lithium ion battery. Among the attractive functionalities, ignition can be controlled on armed or disarmed mode, provides the security related information, such as vehicle statuses like battery level, armed-disarmed etc. on user request via SMS, vehicle location based on cellular triangulation in offline mode and sends accidental statuses to owner and his/her relative. The proposed design of the sensor and the developed device is capable of providing security of a bike in both standing and running situations to keep it safe from thievery and snatching. Thus, a technology is provided that ensures the security for humanity. Such a low cost antitheft system can be of great help to the vendors in the rural area who use motorcycle for paddling from one place to another. The community requires constant use of their motorcycle and thus need a motorcycle security system that is robust and has minimal errors which our system provides successfully.