Elliot Harvey now leads the Little Green Man X30 Tour standings after recovering from an earlier crash to win round five at Buckmore Park in Kent.
The 12-year-old, from Didcot, won each of the six practice sessions, but he encountered problems in the qualifying heats.
In the first heat, Elliot started from second on the grid and drove away to win by more than three seconds.
However, things began to go wrong after that.
In heat two, he finished seventh after being pushed wide when leading.
The third heat was a disaster as Harvey’s kart was hit on the first lap and he had to retire.
This meant that he had to start fifth on the grid for the final.
But the St Birinus School pupil made a flying start and after overtaking two karts on the same corner, he stormed to victory by three seconds from Alfie Brown.
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