An optical fiber comprising: a core having an outer radius r 1 ;a cladding having an outer radius r 4 ≤31 microns; a primary coating surrounding the cladding having an outer radius r 5 ,, a thickness t p > 10 microns, in situ modulus E P of 0. 5 MPa or less, and a spring constant χ P χP =2E P r 4 / t P ; and a secondary coating surrounding said primary coating, the secondary coating having an outer radius r 6 , a thickness t S =r 6 - r 5 , in situ modulus E S of 1200 MPa or greater; t S greater than 9.5 microns, wherein r 6 is 50 to 67.5 microns. The fiber has a mode field diameter MFD greater than 8.2 microns at 1310 nm; a fiber cutoff wavelength of less than 1310 nm; and a bend loss at a wavelength of 1550 nm, when wrapped around a mandrel having a diameter of 10 mm, of less than 1.0 dB/turn..