So what is the reason the model 1 gross weight is set at 850 pounds and the model 2 950 pounds? almost identical in construction as far as tubing size and diameter. So why the difference? possible because power to weight ratio with the model 1 coming out when really the only choice in engine being the Rotax 532. I have ready all the published information about changes made from model to model like wing spar wall thickness and the addition of the inner spars, but am curious as to how Denny aircraft got to the 850 gross for the model 1 and the 950 gross to the model 2 and 1050 to the model 4. Anyone have any info