"We need to hear from anyone who was in the Cartwright Rd area between 9 o'clock Sunday night and 4am Monday morning - please get in touch," Detective Shaun Galbraith of Waitakere police said.
"Whoever has done this is obviously going to try and sell them and we need people to be vigilant.
"If you see a bike like this for sale and you suspect it may be stolen, please let us know.
"It's also a warning to anyone who's offered one of these bikes and buys it, you're buying stolen property and you run the risk of being criminally charged," Mr Galbraith said.