talking 50cc one, hard to find a pic of the box but here it is on a bike the air box on that, the foam inside is maybe 5cmx20cm and 10mm thick gone back to my airbox anyway after getting caught out in the rain twice and pushing it home, i still have my old nrg's airbox to try ? the slightly larger one anyone shed any light?
You could mod the standard airbox by opening the intake holes and using a mallossi red spounge, but you can run a open filter in the rain you just need a waterproof cover for them! You can get waterproof pre-filters for many different size air filters and they do keep water out and arnt restrictive at all. theres a company called "outwears" who make pre-filters!
got a triangle on now, almost had a day problem free, now coolant is leaking out the crank case and it wont start