In a test of D-locks, folding locks, reinforced cables and chain locks, the majority could be broken within just three minutes - even the expensive ones.
The test found that no one lock would provide 100 percent security against a would-be bike bandit, but that in general, D-locks were most likely to stop a thief in their tracks. The majority of chains and cables were found to provide little to no protection.
Overall, 17 of the 37 tested locks were found to be "lacking", whereas just five were found to be effective in stopping or slowing down thieves.
The winners of the test, given the highest "very good" seal, were two D-locks on sale for a cool €80 and €85 each, with two cheaper versions going for €75 and €40 given the second highest "good" seal.
If you want to hang on to your two-wheeled buddy, the watchdog advised that it be locked up out of sight when out and about, and put it behind a locked door overnight.
Most bike thieves "specialise" in one type of lock and carry a special tool to make light work of breaking them. Securing your bike with two different types of lock could also help deter them, said the organisation.