Not that any more opinions are called for here, but I'll spew mine with no demands that it be respected..
During the industrial revolution, the nation and it's artisans were MUCH more experienced with wood than they were metals, and some stuff that would more properly be made of metals later on were still being made of wood..., but conversely, later, when we became more experienced with metals and foundries were on a LOT of iron ore sites, we made a great deal of stuff from cast iron that would have more properly been made of wood.
Either material has it's strengths and weaknesses, especially when the proper disciplines are used in construction. Just as a f'rinstance, a building supported by massive timbers will often resist collapse longer during a fire than one made of steel beams, since the timbers will only burn RAPIDLY until the outer shell is burned and then slow down, but steel beams when red hot all of the way through will soften like wet noodles.
The major attractiveness of metals in constructing machinery are often more about the ease and repeatability of construction than the ultimate strength. Pound for pound, I could build a kart frame that would support more weight from wood than I could from steel. There is just no way in this day and age that I could have it mass produced. We lack both the suppliers and the artisans to do a fast and worthy job of it.
I have worked with both materials for 60 years, and would not rule out either as a good material for a kart, if properly built. No insults intended here. Both materials have their benefits.....Joe
