Redcar team boss Brian Havelock says rider cover is needed after number one Jason Lyons picked up an injury during Sunday's meeting against Glasgow.
The 41-year-old has suffered a triple fracture of the femur, ruling him out of Friday's trip to Scunthorpe.
"I would prefer to sign another rider rather than use guests and I am urgently considering the options available," Havelock said.
"This is a devastating blow for rider and club, time is of the essence."
Lyons joined the Bears at the start of the 2011 season, having ridden for Stoke, Birmingham and Mildenhall in recent seasons.