Thefts of bicycles in Oxford have fallen by 29% since a crackdown.
A bicycle is stolen every 71 seconds in England, according to figures
Thames Valley Police launched a campaign during the summer, after the city was named as one of the worst places for cycle crime in England.
A police spokesman said the new figures were encouraging, but there was only so much officers could do and cyclists should do more to secure their bikes.
Between April and August 608 bicycles were stolen in the city, compared with 852 in the previous year.
Pc Jim Abram said: "These figures are really encouraging. It means there are nearly 250 people in Oxford who haven't become the victim of bike thieves who would have done last summer.
"The police can only do so much and if cyclists use good locks and park up in secure places they will greatly reduce the chances of their bike being stolen."
A survey in April found that Oxford was the sixth worst place in the country for bicycle theft.
There were 1,805 bicycles stolen across the city between April 2006 and March 2007.