clicking noise when idling and no 3rd gear

[justin41414]

my kfx was sitting for about a week or two because i had to order a front sprocket because the teeth broke off so i got it and i put it on and when i had started it would make this clicking nosie when idling like the chain is loose but it wasnt. so i rode to see if the noise would go away sometimes it will go way and somtimes it wont. but when i shifted in 3rd gear it would got to nuetral or you would here this scarchting noise right when you let out the cluch. it seems like somethings grinding.

plz help i dont know what it is and what should i do,

thanks