Training Partner Woes

I'd maybe train with him when your doing easy zone 1 or 2 type runs or bikes but leave him on your more intense efforts if he can't keep up.  

I run/ride with a group from time to time and the group generally splits up depending on ability on the run.  Honestly, I have no problem is someone is fast and drops me.  It is on me to keep pace and if I need an easy day there is no shame in that, I can do my own thing.  The bike is a little different, but I've been making an effort to only ride with people who are very close to me or higher. It bothers me to be cruising around on the bike for an hour or more and feel like you haven't even worked out ...IMO. 

Who knows, maybe they'll rise to the occasion and get faster...

I know where your coming from though.  I used to work out with a couple of guys who just talked too much and were holding me back.  Now I work out alone most of the time and I like it that way....but I am very self motivated so it may not work for everyone. 

So this is my opinion, I think you should evaluate what YOUR goals are. If you are wanting to be the absolute best you can be, then you may need to either do more workouts (on your own) or tell the guy you can't train with him as much and do your own thing. One thing though, this is just my opinion, he may be looking to you to push him. I think if the guy is a friend of yours you need to look at it from his point of view too.  That's my .02.

I have a workout partner who is a much stronger athlete than me (which, frankly, wouldn't take much).  I'm struggling to get through sprints and she's training for an IM.  We meet to train together, but we rarely stay together because of the imbalance in our abilities.  It suits us both because simply planning to meet motivates us to get out there and do our respective workouts.  It doesn't matter that we split up almost immediately.  Maybe having an open conversation explaining your needs to your workout partner is in order.