In November, officers were parked up in a marked police van in Ely, when Corey Whitehead aged 18, wearing a balaclava, drove past them on his Suron E-Bike.
He then attempted skid manoeuvres in front of the van but lost control and fell off.
As he tried to escape on foot officers detained him and conducted a search.
He was then found in possession of 38 wraps of crack cocaine and heroin.
Whitehead also had £2500 in cash and a large knife hidden in his waistband. His mobile phone when examined also showed evidence of dealing drugs.
Whitehead from Caerau, Ely was found guilty and sentenced to 26 months detention in a youth offenders institute.