With her children at her side, her dog's leash in hand and the noise from the roadway in her ears, Rebecca Goodchild had her guard down when the bike hit her from behind about 5pm Monday, connecting with her hip area.

The dog was flung onto the roadway on impact. Ms Goodchild slammed into the concrete path, smashing her shoulder. She would go to bed that night with her arm throbbing and was awaiting an x-ray on Tuesday to determine whether the bone was broken.

Her partner and children - aged 3, 7 and 8 - encircled her after she fell to the ground

"All I felt was a big hit behind me," Ms Goodchild told the Mercury.

"I saw someone driving past on the road and they put their hand to their mouth like, 'oh my god'.

"My kids said, 'oh no ... mum, are you okay?'.

"They [the bike riders] didn't stop, didn't check on me, nothing."

The crash occurred beside Northcliffe Drive, near Aish's Seafood and Takeaway. The bike - described as a black pit bike - was last seen heading eastward along the lake footpath, carrying two people.

Ms Goodchild's partner Justin Oyston was walking a short distance behind her, but had no time to warn her of the bike's fast approach.

"They flew past that quick and then just ploughed into my missus," he said.

"We think it was intentional because they were video recording the whole thing.

"I just wish it was me that they hit."

Mr Oyston said he tried in vain to hail down a passing car so he could pursue the bike.

He said the rider and their passenger were wearing dark hoodies and face masks, with the passenger filming.

"All you could see was their eyes," he said.

"They just didn't care, they've got no respect for anyone."

The matter has been reported to Lake Illawarra Police District. Police are calling on anyone with information, including CCTV or dashcam footage, to come forward.

Contact Lake Illawarra Police Station on 4232 5599 or Crime Stoppers on 1800 333 000.

Berkeley has been the site of numerous close calls involving unregistered trail bike riding.

Police and paramedics spoke out about the issue in May last year, after a 16-year-old rider was involved in a horrific crash on Hertford St.

The rider's 17-year-old passenger, Dejah Stewart, was thrown from the bike and tragically died in hospital four days later.

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