Continue roasting the ham, uncovered this time, basting every 15 minutes or so with more maple syrup as well as any pan drippings, until an instant-read meat thermometer inserted into the thickest part of the meat without touching bone registers 170°F (77°C), about 1 1/4 hours more.☞ TESTER TIP: If the ham starts to singe or turn too dark, tent it loosely with foil, uncovering it at the end to get it back to crunchy-crisp.