That frame is an odd one, definitely not a Hagon even though it seems to have a Hagon swingarm.
My guess is that it's a locally made unit probably based on Hagon geometry. Based on what I can see in the photos and phoning a more knowledgable friend I/we've come to the following conclusions......
*The swingarm appears to be early Hagon or a good copy.
*The rear wheel looks to be a Rotrax item
*Campagnolo front wheel with Hagon sticker on the backing plate as per early Hagons.
*Jawa speedway seat and Hagon Sand Tracker rear fender as Jim stated.
*Forks appear to be early 32mm Yamaha steel stauntion from an AT1 or something similar.
*The frame is
not oil in frame so the evidence points towards it's being made for a 2 stroke (
green number plate, bracket on r/rear subframe to mount an up pipe expansion chamber, most probably a Villiers based 2 stroke going by the right side drive and the shape of the engine/trans plate.
As the photos below show it's nothing like an early Hagon grass tracker. The first Hagons were based on their speedway frame which in turn was copied from the Rotrax design. Hagon produced a kit (
see below) to convert Hagon and Rotrax speedway diamonds into springers which is nothing like this frame. It's nothing like any Hagon, my 2t Antig or even an Elstar. It could be an Aussie made Taylor but without having one or being able to find a reference photo I'm not sure. The bike's unique but it's a bit of a roughie, needing a shitload or restoration...forks, blasting, paint, wheels, engine plates and much more. I wouldn't pay much more than a couple of hundred for it.
Below: Hagon Springer kit for a speedway frame