Your mare is a bay roan her sire blue and roans go back 3 generations on the top side If you breed to will get roan?

The likelihood of getting a roan foal from breeding a bay roan mare to a non-roan stallion depends on the specific color genetics involved. Roan is a coat pattern caused by a dominant modifier gene that causes a horse to have a mixture of white and colored hairs. In the case of a bay roan, the base color is bay, which is a reddish-brown color.

If the bay roan mare carries the roan gene and the stallion does not, then there is a 50% chance that each foal they produce will be roan. If the stallion also carries the roan gene, then the chances of producing a roan foal increase to 75%.

It's also worth noting that the presence of the roan gene can mask other color patterns, such as bay or black. So, if the stallion carries the roan gene, it's possible that the foal could be a roan bay (a bay horse with a roan pattern) or a roan black (a black horse with a roan pattern).

To determine the exact likelihood of getting a roan foal, it would be helpful to know the specific color genetics of the mare and stallion in question.