Question about my jetting for winter

[shogs]

I have heard that for winter you need to richen up the jets a little when its really cold out. My banshee ran decent in warm weather and now when I start it up it wants to foul out and once its warmed up its hard to get going in first and bogs a lot. If I richen the jets wont it bog even more when I start it? I'm just kinda confused why it runs so bad right now. Sorry if this has been covered a lot just can't find what I'm looking for. Thanks in advance for any advice.