The airfield I have has a grass runway and not even a short one, so I needed bigger wheels that could float in the grass instead of sticking. This wheel has a diameter of 90mm, is 26mm wide and it's compatible with the original legs.
I used a 0.6 nozzle both to save time and to have more resistant layers, but you can use the diameter you prefer. I printed the smaller rim and the tire in PLA, with a single perimeter and lightning filling to limit the weight. The spokes are printed in TPU to absorb shock during landing. The total weight of the wheel is 34 grams, about double the original wheels.
Assembly does not require glue.

In the photo there is a wheel with an arrow indicating the direction of rotation, it would be the left wheel: if the right wheel have the spokes oriented in the opposite direction, during the flight the wheel will turned by the air so when landing it will already be in motion, limiting the friction with the grass. Of course this is not mandatory.

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Alternative wheel (v2) - I made some small updates, if you have already printed the wheels you don't need to reprint them, otherwise consider this variants:

CUB Big front wheel disc v2 - the central hollow part is deeper and the right and left side are slightly thinner. Also in the central hole for the wheel pin, I made a small space to put a small amount of grease to improve rotation. This component is compatible also with the first version of the spokes.

CUB Big front wheel spokes v2 (TPU) - I reduced the number of spokes to improve elasticity. Weight has decreased by 3 grams each wheel, but that doesn't make a difference. This component is compatible also with the first version of the wheel.

CUB Big front wheel tire with sprokes - in one of the makes, spokes and tire were joined to be printed entirely in TPU: this file is the tire and spokes joined in one piece, with a small aesthetic improvement. This component is compatible also with the first version of the disc.