Heres a antique foto of the same era bike.
Thats a really large intake manifold, HDs have the manifold lower , not at the top .and some really long push rods, no push rod tube covers, oil tank behind the rear cylinder vs above. Note the horizontal positioning of the spark plugs.
Look at those leafsprings, almost like they were borrowed from a sidecar, works in the front so probably a good idea for rear suspension in 1914. Round stock fender brackets just like on HDS of the same time period.