You can do whatever you want to the verticals in the wing spars, you can extend the stub spars or the outer spars, you can beef up the wing attach fittings, change the wings and wingtips- but I believe prior analysis has shown that the weak point in the whole thing is the connection right at the spar and the fuselage and that is where the maximum moment will occur on a cantilevered wing. Increase the load that the spar has to carry and you need to increase its ability to transfer that moment to or from the fuselage. If you don't, the wings fold up without you asking them to.
With the stock wing spar depth and flanges, you simply must respect the designer's stated max gross weight for the aircraft or look for something else to build and fly. Oh, I guess there is also the option of designing a different spar. Somebody shoot me down here... aero engineers, please... I don't own a KR, have never built one, and don't even own a set of plans so I'm not sure what I'm even doing here. Oscar Zuniga Air Camper NX41CC "Scout" Flying Squirrel N2069Z "Rocket" Medford, OR website at http://www.flysquirrel.net
