The related Hooks are "_ClipLGear" and "_ClipRGear" (and possibly "_ClipCGear" too) ...
Thank you for your advice.
There were difficulties in adjusting ClipCGear. This value seems to affect the stability (the center of gravity) of the plane. When I adjust this value incorrectly, I will feel the plane shake a lot when entering the QMB. So, I had to find the value with the least fluctuation.
Nieuport11 now looks stable on the ground.
And I can't share my changed values because the change of the values may have a bad effect on take-off.
I'll take that risk alone.