Originally Posted by campbellj
I took out the fiberglass spar. The only weight I added was a carbon rod in the vertical stab and any weight the arrow shaft and gorilla glue could have added.
Then you only added a few grams and that is not the problem. My arrow shaft only weighed 2 grams more than the spar that was removed. Also I use the 2 pencils in a block of wood method to measure CG and just sharpen the existing erasers that are on the pencils. Doing it upside down works ok on this plane.
If for whatever reason you need to move the battery ahead, an easy way is to simply switch the locations of the ESC and the battery. That's what I did when I first got the plane and wanted to get it to 70 as per the manual. Now the battery is back in the battery compartment and it is pretty close to 77. It would be a good option for somebody using a tail-cam.