I know the basic way to get better at transitioning from bike to run is to practice transitioning from bike to run, but what is the proper amount of running to do after certain rides, and how often is it good to do? Also, going from swim to bike, even though its not as bad, how often do you guys do that in training?
Anyone?
What distance races are you training for?
If you can run… you can run after cycling.
We’ve had some lengthy discussions around here about transition workouts / bricks. search 
Olympic…?
I train for Olympic distance races primarily too. I never really used to do bricks, only races really, just raced 10-15x a year. Never really had trouble running off the bike too much, but I come from a running back ground. Best 10k off the bike last year was in the 39’s.
This year I have a coach and she has me doing bricks more often. At least once every 2 weeks. I think the longest I have run off the bike is 30 or 40 mins though from what I remember, more focus is on quickness of leg turnover off the bike.