A group of Osborne Park locals are revolting against Main Roads, placing their own speed limit signs along Main Street after the authority refused to include the "unsafe" pedestrian area in a 40km/h speed reduction trial.
Community group, Main Street Co-op member Tania Pietracatella said locals erected the signs after becoming fed up of cars speeding through the business and shopping precinct area, which made it difficult to cross the road.
She is part of a growing number of community members who want the Main Street strip between Eldorado Street and Cape Street, currently zoned 60 km/h, transformed into a vibrant, pedestrian-friendly community hub.
"The traffic on Hutton and Main Street has been an issue for years," Ms Pietracatella said.
"I've grown up in the area, and anyone you talk to that knows Main Street will say the same thing but they've never done anything about it.
"I think, now that Beaufort Street and Oxford Street has been done - streets that were really busy and main arteries - I think we need that here as well and we're not sure why we can't have that in our area.
"No one wants to go have a coffee on a freeway."
The unauthorised street signs are also supported by the local Liberal MP, Chris Hatton, who wants to stop "idiots" from flying through the area.
The black spot, in 2014 and 2015, had 69 crashes, 38 causing major damage to property and eight requiring medical attention.
The City of Stirling requested the 40km/h trial, taking place along a 200m strip of Main Street between Hutton Street and Federal Street, be extended to an 850m trial between Eldorado Street and Cape Street.
But Main Roads, the agency responsible for determining speed limits in WA, chose not to extend the trial.
"Main Street is a local road under the care and control of the City of Stirling," a spokeswoman said.
"Main Roads has offered the City of Stirling an agreement in principle to conduct a time specific am/pm 40 km/h trial for a two-year period at Main Street Shopping precinct between Federal Street and Royal/Hutton Street."
Ms Pietracatella said the group was unsure if it would face any consequences for erecting the signs.
"I don't know if we'll get in trouble, we'll just see, I guess," she said.
A police spokesman said a person could face a fine under the Road Traffic Act for erecting a speed sign without permission from the relevant authorities.
