I've been pondering some more, and think perhaps the chainstay is simpler to make from the ground up but using steel bar and "forging" in the sense of heating and bending after machining the tube and frame holes at the "rear" end? Suitably large hex bar as that gives a flat surface for the frame stud for behind the engine, I could turn and bore the end of the bar for the frame tube to fit into, for weld or braze, but before doing that I could heat and bend the bar to go around the sump / oil pump and then flatten and finish for the front frame through-stud - that's forging like a blacksmith would do for a horseshoe. The left side is the same, but simpler, less bending, and the rear of the chainstay isn't nearly as complex. I know originally the forgings and tube would be furnace brazed (at least I think that the case) but as MIG is more accessible perhaps that's the better option for me and my skill levels.
well done mate ,yes great speed for sure,the wind is a big thing ,it makes a huge difference out there,recon we will head out again,same class,500 yamie,cheers
