Hi, my good housekeeping recipe book gives cooking times per weight of bird, so for 1.4-2.3kg range (sorry, that's the lightest) it says 1.5-2 hrs cooking time.
"Season, then smear with butter or oil. Put the turkey straight into a deep roasting tin and cover loosely with a "tent" of foil. Roast in a pre-heated oven at 190/375f/gas mark 5, basting frequently to keep the bird moist. Fold back the foil 45 mins before the end of the cooking time to brown and crisp the breast."
The important thing, is as with chicken, make sure the juices run clear to know it's ready. HTH.
Ty...have actually just loaded dishwasher after a lovely meal. Eventually found some online guides after deep searching which calculated anything from just over an hour to 90mins so went with the latter. Was perhaps very slightly overdone.