The school students died on the spot when their bike, after losing control, turned turtle and fell into the ditch on the Morigaon-Dharamtul Road, police sources said.
The boys were identified as Yasin Ali (17) and Sarif Ali (15).
The new motor-cycle, bought by the father of the boys three days ago, neither had a licence number plate nor did the youths have driving licence, police said.