Consistently shooting high left with new bow

[Tradtical Commando]

Can someone shed any light for me? Here is what I know:
-For some reason I very consistently shoot about 8-10" high and 6-8" left with baseball size groups from about 10-15 yards-ish.      
-I upped my draw weight by about 5 lbs or so.
-I swapped from my old 54" recurve to a 64" long bow. Until now the recurve was all I had ever owned and shot. I have never been robin hood, but I've always been decent.
-My bow arm shoulder is unusually fatiguing quickly.
-I have always mildly looked down the arrow but now have a tough time lining it up accurately. Could I need to can't more?
-I feel like something isn't right with my form, but am playing hell figuring out what.
-I have always been able to shoot accurately from various stances and positions, but now can't seem to shoot accurately at all.

[McDave]

The chances are, your new longbow is not cut past centershot, whereas your old recurve was. Until you get used to it, this will make you hit left with the longbow.  My friends who usually shoot longbows have the opposite problem: they hit right when they switch to a recurve that is cut past center, and so they build out the strike plate with a ghastly stack of leather.

The thing to do is to pick a type of bow that you want to stick with and then shoot it until it comes on target for you. So if you want to stick with the longbow, just put up with it for a while.  You can move your POI a little bit to the right by switching to a softer strike plate, but not 6" at 10 yards.

If you're not used to the increased weight, and your bow arm gets tired, this can cause an upward creep.  Be conscious of putting your bow arm on target and keep it there. If it begins to drift up, then stop shooting for a while.

[Tradtical Commando]

Ok, thank you for the heads up. Ive never really had any kind of shoulder fatigue so I thought maybe I was unknowingly doing something cockeyed. Thank you again for the input.

Couple things come to mind.  Your arrows "may" be too stiff for the new longbow.  Sometimes a longbow forces you to shoot with a lower grip.  That can put a lot of new stress on muscles, tendons, etc., until you get used to it. I wouldn't be too concerned about the shoulder--yet.

[damascusdave]

I went up about 5 pounds at a time in draw weight from 40 until I hit about 65 pounds...I can shoot 60 pounds all day long but only about 20 shots at 65 pounds of draw weight...possible that you are simply overbowed by adding what appears to be 5 pounds of draw weight...if you are relying on the marked weights on the bows it could be more than that

DDave