Recommended pace for bike leg - first HIM

With no logs to review it's hard to help you answer your question.  My only thoughts would be that you trying to keep yourself down to 17 mph will be impossible because you will feel like you should be pushing it harder.  You can review my race report on the Pigman Long course and see why buring out at 20.5MPH, even though I felt awesome for the entire ride ended up being a very bad idea.

Seems as though a 17mph pace would keep you in pretty good shape to not have a total collapes on the run, like I did. :-)

I recommend you pace yourself either by RPE, HR or power.  Pacing yourself by a given speed is an easy way to burn yourself out because you're not taking into consideration hills, wind, heat, nutrition etc.

All that said, I think you will probably go faster than 17 mph with a proper pace to run well off of based on the times you listed for your Oly. 

For what it's worth (basically nothing as we're two different people) but I did about the same bike leg in my recent OLY's 21-22 mph, did slow the run at about 4 miles however. Started training by HR and now I understand why. I'd ideally like to be able to do 18.5ish mph on my HIM in a week but am going to force myself not to if my HR says I shouldn't. I will be running the whole 13.1 because I started training with a HR. With RPE I'm 100% positive I would crash the run

Zone 2 for about 45 miles and then move it up to Z3 over the last half hour IF you feel great. There is no such thing as a 'great bike split' and then a lousy run. That's called a terribly executed race.

MPH is not a good metric to use, especially if you have headwind, tailwind, cross wind, heat, cold or any thing else that can negatively impact your mph plan. Use HR or Power and you'll have a much better experience.

If I was in your boat (and sufficiently trained for a HIM), I would  try to ride it at an effort that is about 88-90% of the effort you used for your Olympic.

This is exactly what I did and I had a great run (and race). I kept it in high zone 2 and only went into zone 3 for hills, and even then, kept it low zone 3. If you train with HR regularly, this is a great way to go.

I just ran the ran as I felt - my HR on the run for the entire thing was zone 4, I think, right from the get-go, but if you're not a FOP runner, you'll probably have to go zone 3-4.