They are Godsway Sedofia, 19; Seraphim Torgbor, and Destiny Adzakpo, both 18.
Each of them will serve 20 years behind bars in hard labour.
They pleaded not guilty.
Chief Inspector Seidu Kodua, who represented the republic, told the court presided over by Mr Isaac Addo that on December 22, last year, Sedofia hired the motorbike operator from the Akatsi Central Market to Atidzive.
On reaching a section of the road, Sedofia pointed a gun at the rider and ordered him to stop.
The rider obliged and Adzakpo who had laid ambush nearby came to assist Sedofia to dispossess the rider of the Haojue motorbike, with registration number M-21 VR 3225.
The prosecution said the two also seized the crush helmet from the rider.
According to the prosecution, the victim later informed his friends who were in the ‘okada’ business of the ordeal he went through at the hands of the robbers.
Soon after, the victim had a tip-off that Sedofia and Torgbor were seen on speeding bike at Glikpome.
Victim and friends
The victim and his friends then proceeded to the house of Sedofia where they found the crush helmet in his room.
Subsequently, they arrested him and handed him over to the police.
The court heard that Sedofia admitted the offence in his caution statement and mentioned Torgbor and Adzakpo as his accomplices, leading to their arrest on Christmas eve.
The motorbike was later retrieved on the premises of the Keta Municipal Hospital, the court was further told.
The prosecution said another accomplice; Robert Sedofia was on the run.
Passing the sentence, the court said although the accused persons pleaded not guilty, the prosecution proved its case beyond doubt.