Be Aware!   Residents of a Cambridgeshire village are taking a stand against speeding motorcyclists, who are alleged to be using a hump-back bridge as a 'take-off ramp'.Villagers in Somersham have formed a safety partnership under the Speedwatch road safety initiative, whose slogan 'Promoting safer driving in communities through education, rather than prosecution' aims to curb dangerous driving in UK villages by using local residents rather than Police Officers. The group has no power to enforce laws or prosecute.One member of the Somersham Speedwatch group claims to have 'clocked' a rider travelling at 64mph in the 30mph zone, saying the bridge had been a problem for a while with bikers and some car drivers using it as a take-off ramp.He said: “Having launched themselves at speeds of up to 55mph in one direction they turn around near the Somersham garage and try it again in the opposite direction where just last weekend I witnessed one biker, after a successful jump, roaring off at 64mph still 100m inside the 30mph zone.“We only do it where there is a threat to pedestrians, children, or emerging traffic.”Information gathered by Speedwatch is given to police who send out warning letters. Repeat offenders may get the letter delivered by a police officer, and continuing problems can lead to formal speed checks.                                                                                                                                                                              

HA! i went over a humpback bridge at 60 once, my arse left the seat but the bike didn't leave the road.
would i ever do it again? probably but not quite as fast.
i've yet to see a humpback bridge in a built up area. they're always over canals where i go riding which barring one or two trips is always up north.