Did a wheel model on my Apprentice S 15e
 

I tend to take off and land in grassy areas so I saw others do it and decided on larger wheels. I saw others use mismatched size wheels because of the front landing gear spring. I wanted all the wheels the same size. I went with 3 1/4" Dave Brown Lite Flite Foam wheels. They are heavier than OEM but the plane wasn't out of balance. First flight with them is in about an hour. https://cimg2.ibsrv.net/gimg/www.rcu...beea078985.jpg
https://cimg4.ibsrv.net/gimg/www.rcu...0d305d0a86.jpg
https://cimg6.ibsrv.net/gimg/www.rcu...e4a68be0ac.jpg

Thanks for sharing.

The mismatch you're referring to is normal - most tricycle gear airplanes have a smaller nose-gear wheel than the main-gear wheels since the mains carry a majority of the load.

Passing on a technique someone told me about to improve the look of those Dave Brown wheels: stick the wheels in the freezer for a while to stiffen the foam tire, find a long screw and nut to use as a mandrel that fits the axle hole, then chuck each wheel up in a drill press. With the drill press running, use a Dremel and sanding drum to shape the tire and give them a more pleasing rounded cross-section.

The stock wheels all came the same size but I have noticed that. And what a smart idea putting the tires in the freezer. Thanks for sharing that!

on hard runways a slightly smaller front wheel will work just fine. on grass,... I prefer the front wheel to be at least the same size as the main gear, or even slightly larger.

Yeah, I didn't want a smaller front wheel. And for my plane I think what I have on there is the largest that will fit.