We have numerically investigated supercontinuum generation in photonic crystal fibers with zero-dispersion wavelengths in the vicinity of 800 nm by using an input pulse with a peak power of about 20 kW and a width of about 10 fs. The effects of fiber dispersion and the input pulse parameters on the generated optical spectra are quantitatively analyzed. The propagation length necessary for the generation of a soliton in the anomalous dispersion region is found to depend on the zero-dispersion wavelength of a fiber. For the generation of a sufficiently broad spectrum, the photonic crystal fiber should be longer than the soliton-generation length. In addition, a spectral recoil effect appears when a solitary wave splits the dispersive wave into two parts.