devonboy161616

hi all,im fitting a tw125 4 stroke into my husqvarna wr 125 2stroke!i have mant reasons for this here are a few: yamaha motors go forever and are the best,my husky is a massive and a very good looking bike,i dont want to ride anything bigger and only use the bike for summer rides,insurance and road tax are dead cheap,although the huskey is very very quick i dont want the hassel to maintain the engine and mix oil with the fuel........any way now for the question...my husky has an expantion pipe and an alley tail pipe,can i leave the alley back box on when i fit the yamaha engine? thanks