Four firefighters were hurt as they battled a massive blaze in a Bronx bike shop overnight, officials said.

The fire broke out inside Arrow Cycle on White Plains Road near East 228th Street in Wakefield around 8:20 p.m. and grew to four alarms, the FDNY said.

Thirty-nine units, including 168 firefighters, responded to the blaze — which burned for more than four hours.

Three firefighters were taken to local hospitals and one was treated on the scene — each of them with minor injuries, officials said.

The cause of the fire is under investigation.