I'm using a Honeybee King 2 in this example because the Esky models, HBK2 and Belt CP, don't use industry standard hole spacing on their landing gear. Other manufacturers may not, either, but a comprehensive list is not available. (Please note that some HBK2 frames "battery hangers" will accept the standard 42mm holes, and some won't.)

On a Belt CP, the offset is only about 3mm and hard to see when the landing gear is mounted, but other helis may have a larger offset and you may want your landing gear centered, despite the small advantage lost to the balance as described above.

Fortunately, this can be done in as little as 1 minute. You generally only need to make the holes about 1/2 mm larger as shown in RED on the illustration to the left. We recommend not making the holes too large as a small camber is preferred. The HBK2 is not really heavy enough to make much difference, but it's still nice.

We've enlarged the holes 2 ways, and in each case the stock landing gear still fits. The first way (takes a little more time) is to use the pointed end of a hobby knife to make the holes oval shaped as shown. 

The second way is to use a 3/32" (about 2.4mm) drill bit to make the holes larger. A drill was not necessary, just the bit. It made a nice, finished hole.