I agree with the above poster. Bi-amping serves no purpose whatsoever. But to answer your question, no you cannot with the unit you are considering. It a 2 channel amp only and has no unused internal amps to use like an AVR. Even with an AVR, bi-amping by using the unused channels brings no benefit.
Just hook up your B&W's to the Marantz normally and enjoy the music!
Marantz PM15S2 LE, Oppo BDP-103, Simaudio Moon 100D DAC
VPI Traveler V2 with an Ortofon Rondo Blue and Simaudio Moon 110LP, Technics SL-1400 with an Audio Technica AT-14sa and Pro-ject Phono Box S
Dynaudio Focus 260's, Rel T-1 and a Panasonic TC-P54S1.