Its also a function of how you ride your bike - high kerbs and such under power are such a bad idea.. the wheels arent designed for that sort of stress.

Its worth beefing up the spokes and also having more attachment points for the sprocket... its also worth looking at your riding style and being as smooth as possible - snatchy means stress which means more fuel used and will be detrimental to component wear

good luck with it..

Jemma xx