mosewell

ok i'm new to all this and i just bought a 01 Banshee my first one its stock as far as i know besides the DG tips and an K&N airfilter was on there when i got it.. it didnt have any spark and the guy said it wasnt gettin any gass to the head he said it needed to be rejetted. so i bought it and i fooled around with it and got it running without new jets and the spark problem was the cdi. i got it all done she was running good then it started gettin cold out. now i cant do anything with her. shes fooling plugs and hard to start not running right. i dont have a clue what this could be.. i'v read things on here where ppl have rejetted for the winter but they have alot of mods one there bike so it wouldnt be the same as mine... anyone know what this could be. any help would be grate! Thanks