The number of bikes being stolen in Dublin increased by almost 50% last month.
434 bicycles were taken compared to 297 in June last year.
Nationally there has been a 40% surge in the problem with the Dublin and Eastern regions worst affected.
Colm Ryder from cyclist.ie says there is huge demand for bikes at the minute.
"There has been a massive increase in the number of bike sales in the past few months during lockdown
"Shops were even running out of bikes.
"But often people buy bikes and they either don't buy a lock or they buy a very cheap lock which is easily broken by thieves."
Mr Ryder said the theft of a bike has been shown to deter people from cycling.
"When we did a survey on bike thefts a number of years back in Dublin Cycling Campaign, a very high percentage of people just said 'look I'm not gonna get back on a bike again, it's just not worth it. I can't afford to buy another bike'.
"It is particularly difficult to insure bikes and that is an issue that a lot of people have as well."