On Sunday, a 20-year-old man was airlifted to Liverpool Hospital with suspected head and spinal injuries after losing control of his motorbike, which he was riding illegally on the reserve.

Mark Ryan, whose property backs onto the park, said riders have been riding illegally on the reserve for some time, and he has long held concerns someone would be seriously injured or worse.

He said he has contacted police no less than 10 times in the space of a year about the problem, yet the issue still continues.

"Even after everything happened on Sunday, another idiot was out there the next day" he said.

Mr Ryan said he contacted police at 4.13pm on Saturday to say a guy was racing up and down the far side on the reserve on a bike.

"I've been complaining for over 12 months; it's pretty foreseeable that is it only a matter of time before something terrible happens."

Acknowledging the difficulties of catching the riders in the act, Mr Ryan said he is not critical of the police, but said something needs to be done to prevent anyone being injured again, or worse.

He said he wasn't at home when Sunday's crash occurred but returned not long after to see paramedics working on the victim.

"I just thought 'oh shit'."

He said bike riders get up to 80 or 90 km an hour along the reserve, even ride on the footpath or through a nearby playground.

"It's a very high risk, flying up and down the paddock at 80 - 90km an hour, if something goes wrong they are in deep poo."

He said you can't account for human stupidity, and as the area is so accessible, he is calling on council to install a bike proof fence to stop them getting onto the reserve.

Mr Ryan said he was quite distressed arriving at the scene on Sunday and doesn't want to see it happen again.

Chief Inspector Luke Rankin, Crime Manager with Chifley Police District, said officers had taken note of the incident, and encouraged people to continue to provide timely information to police.

Chief Inspector Rankin said police will use any information they receive to target offenders.

He said police want to speak with anyone who may know the identities of riders using the reserve, as it can be challenging for police, to intercept offenders who are on unregistered bikes. He said any information would help police to target offenders and urged people to call Crime Stoppers on 1300 333 000.