GP Shoestring
Some people have been mounting the landing gear backwards in ERROR and this causes the airplane to nose over.
The Shoestring has a long nose so you must push all your radio gear to the back of the radio compartment to get it to balance.
I have my switches and receiver behind the servos and my battery is in the turtledeck behind the trailing edge of the wing. With this setup and the OS61FX with Bisson Pitts muffler, it balances on the money and has never nosed over even in the long grass I fly off of.
Yak
P.S. This airplane is one of the best flyers I've had in over 30 years of flying.