Gilera Tiger Cross

Hi i have a 50cc tiger cross engine and exhust and ive put it in a Yamha Dt frame (ive onl bolted it in so the engines 100% orinal with not bits cut out.
ne ways it wont run hehe dont think it likes the yamaha frame so i was wondering if you guys knew any thing i could do to try to get it going and i think it maybe the yamaha elrtics not giving it a bigg enough spark so if i couldnt get it running i was just going to sell exhust and eninge i also think the carbs oringal but i ant sure do you guys have any idea what these parts would go for??
Thx alot
Steve