I don't know if this is the picture or not but that second picture looks like the beam has a slight deflection in it. If not, checking in beams is common as the dry and move constantly and that doesn't make the timber structurally unsound. This checks/cracks will open and close because the outside layer will pick up and lose the moisture as it dries, therefore nobody fills this checks with epoxy fillers because that will not help. It became common to treat this cracks as a decorative detail which brings out the unique quality in wood and where it's being used. Good luck

Thanks. yeah the other side of the board does not even have a support.. so just the rafters are holding it up. I cant answer what cracked it but correct.. i guess there is some structure support to it or it would have never cracked.. I guess collar ties will not hurt anything? Or I wonder a 4x4 or one of those jack supports would be better? although it is probably 20' up from my garage floor to the ridge board. Any thoughts on a what to use for a 20' vertical support beam? Thanks.

Actually it's a poured-in-place concrete "bond beam" located at the top of a structural unit masonry wall to tie the structure together horizontally or as a lintel over an opening. This one is a perimeter bond beam at the top of one story walls. Because the wall is hollow structural clay tile and the beam is formed with wood I suspect it's not being built in North America. This is what a perimeter bond beam in a unit masonry wall would look like in the US:

Thanks everyone! The beam is probably about 8" wide and maybe 12" tall (this includes the sheetrock of course). It's a townhome so it spans the other units wall-to-wall. It's supporting a second bedroom upstairs (12'x14'), which I converted to a home gym 2 years ago. Luckily I'm small so I don't have a ton of weights up there. I have a squat rack (200 lbs), barbell (45lbs), dumbbells (100 lbs total), and plates (180 lbs). I also put down 2 layers of plywood + rubber flooring up there to distribute the weight of the equipment for a 6'x8' raised platform. I never deadlift or slam weights. It may sound heavy but I think if you add it up it's not really much heavier than heavy duty furniture. I recall checking the building codes for load per sq ft according to the size of my room and I was still below that. I have not observed any buckling of the floor or separation of the floor from the wall. I took ownership of this home 3 years ago and if I look at my inspector's old photos of the garage there is one area where I can see that the crack was already there. The others I can't tell since his photos were too low-resolution or far away.