BlackSheep-1 is so correct about too forward or rearward of gear placement. A good starting place is to have your axles as close to even with the leading edge of your wing when looking down on the plane as it sits on the groung from above. You need to have the tail elevated so that your center line of the fuse is parallel to the ground. This works very well with a C/G that is about 25% of the cord of your wing. It can be a real close measurement in some cases. On gear that fold either inboard or outboard this has worked very well for me. I really don't know about rotating rearward folding gear. This may not apply. This may or maynot help.