Verbal extensions occur in Grassfields Bantu languages and their presence and identity have been established in a good number of the languages including Babanki (Akumbu & Chibaka 2012), a central Ring Grassfields Bantu language of Northwest Cameroon. Hyman (2013) contains a presentation and reconstruction of Proto-Bantoid verbal extensions with a significant reference to Babanki. However, there has been no focus on the morphophonological processes (vowel deletion and fricative strengthening and weakening) caused by the addition of extensions in this language. The extensions themselves are toneless and only receive tone from the verb root. This paper accounts for the changes using classical Generative Phonology and concludes that true word final consonants in this language are only nasals and the voiceless velar stop, and that the voiceless fricatives [f] and [s] are exceptional cases that verbal extensions seek to regulate.