Bicester scored four tries to earn a bonus-point 26-21 victory over Drifters in Southern Counties North.
In a hard-fought, end-to-end contest, Bicester led after five minutes when Francis Wiese was on hand to stretch across for a try, converted by Dan Spencer, before Drifters replied with a converted try of their own.
Ollie Ashton then put his side ahead with a penalty, but Spencer and then Wiese both powered across for converted tries as the visitors took a 21-18 lead into half-time.
Bicester extended their advantage early in the second half as, after slick inter-passing by Spencer, Matt Dye and Mike Harris, the ball was transferred to the right, where James Grosvenor sent Ryan Gallacher careering over.
Drifters again replied and reduced the deficit to five, but Bicester resisted further pressure to cling on to a memorable victory.
They host High Wycombe this weekend.