Hi when my long bow is unstrung the upper and lover limbs are straight, but when strung the upper limb looks like it is twisting, shecked the string grooves and one groove is deeper and longer that the other, can this cause the limb to be twisting, thanks for any help.

Jersey,

Yes.  But your thread would be better in the bowyer section, where it can be answered by people that really know how to help you.

Good luck.