Well l had one in such a mating - my blanket tri girl, with pretty much all tricolour behind her, to another blanket tri male with a lot of lemon/white behind him. Because of that, I was hoping for a bicolouir bitch from him, but I just got one bicolour male, who we kept, in a litter of 5 as I recall. So I'd suggest probably not, depending on what colours are behind both. However, never having to worry overly about colour in the breed, I'm not much of an 'expert' re colouring and genes. It would appear that tricolours mask bicolours - going by a kennel here who generally produce lemon or red and whites who went out (they needed an outcross at one point) to a predominently tricolour bloodline, and started to get tricolours. My boy had, as said, a lot of bicolours in his background, but also a very dark trricolour, which obviously affected him and what he threw.