Split front fender over a leaf spring, fork truss that forms a triangle under the stem, mechanical throttle linkage, and shape of the tank- Appears to be a 1912-1917 Indian.
The headlight seems oversized and may be a aftermarket accessory, or maybe that's just a trick of perspective in the photo(?)
Great bike & a couple of babes, that was one lucky guy! No wonder he’s got a big smile!
-Mr. B.