How to deal with a busy research partner? I'm working on a research, and I have a partner. We both should be working on the same tasks, but he's very busy, as he has teaching load and I don't, so I end up doing most of the work myself.
This is not a big problem to me, but my advisor sometimes blames us for delayed results or little achievements, and I find it not fair to be blamed because he expects an outcome of two when there's actually only one working, and I get embarrassed to tell him that it was only me, because my partner is actually also my friend.

How does one deal with this situation? I know my partner is very capable, this is not an incompetence claim, it's just he has little time compared to me.
As the comments have said, you need to go with your partner and explain this to your adviser face to face. It's not an incompetence issue and you need to make sure that you make that clear to your partner - it's a workload balance issue. 

At the end of the day though, there are only two options available:


Either your partner reduces their outside workload or,
Your adviser reduces your workload to account for it.


This is something that needs to be decided between the three of you. 

However, I'd strongly advise that after you've had the talk, that you put in place a very rigorous project plan for your next tasks with a strict timeline. Often, this situation ends up just repeating itself as your colleague says 'oh I'll find more time' or your advisor says they'll slacken off but not much happens, so a rigorous project plan helps highlight if the talk has worked or not.