For that very reason most of my Osage bows are sinew backed. Last one I built is holding nearly 3 inches of reflex, and is a fast shooting ,smooth drawing bow at 45lbs, and a little over 25 inches of draw tillered to 26 inches, and 58 inches nock to nock. Heat treat the belly on a form after floor tiller, and get every thing lined up, and then sinew back the bow. Make sure the sinew is dry before you start the tillering process. Good info above. Good luck.