Is there good bicycling in ansa borrego?

Yes on Road and even a lot of trails off road

There are plenty of roads to bike on. There are also plenty of off-road areas to bike on. Not much for small children that is safe though.

I don't know about bikes, but in the surrounding areas there are a few hiking trails, be cautious because if you end up in ocotillo wells which is also in the area, there are fast moving off road veichels in the area.