I know the gearing is 15/38 but i want to know how many links the chain is, and how many would it need to be if i were to go up three teeth in the rear

 

Stock is 94 links. And according to the Rocky mountain atv site, add two links per every 2 tooth change. So a 98 link chain is needed.
Something else to consider..i just changed the front sprocket to a 14, and i ended up with almost the same ratio..and the chain is stock. Just changed the front sprocket,( from Rocky, for 8 bucks,) and its just fine. Alot cheaper, and just as good as changing the rear sprocket and chain.

 

first off i appreciate your reply. the link info is useful. but i am not only jumping up teeth in the rear sprocket i am also lowering the front . in order to have a low gear bike for about a 100 drag. also how much of a difference did you see when you dropped to a 14 tooth front. thanks

 

If youre also doing the front, then you could probably get away with a 96 link chain.
Havent ridden it much since i did the sprocket change,but it should be a good 7% difference in torque to the wheels. I did the change mainly to restore some power which will be lost, when going up in altitude this summer, at St Anthony. Im not very concerned about top speed, so i dont mind the gearing down, and it should help in the slow trail riding in MN, as i wont have to slip the clutch much to keep it moving at a slow pace.
If you do both sprockets, it should really pull hard...but youll lose about 8mph on the top end.