BigJoe, from a previous post you stated you cut the logs in half to remove the pith.
I occasionally get small cracks on the bark side if the log is really large (20+) but they are fairly minor. Cutting through the pith, as you do, should allow the wood to shrink back on itself with. Maybe the heat in your basement is too high or the humidity is too low for a sudden change. Maybe you are not getting the pith fully cut out? I would rather lose a 1/2" from each side and know it is gone than take a chance.
If you can post a pic of the problem it may help.
Some wood is just notorious, in my case Holly. If I dont take the pith out it will split no matter what I do, even if it is only 6 diameter.
This shows about a 6-7 section of Holly. If you put a straight edge to it (a piece of paper) you will see it shrank back about 1 in the half section of log. That would be a 2 crack, or a zillion little ones in a 6 whole log. No cracks from the bark side.
They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety. Benjamin Franklin