I think that many IM training programs are a little slack when it comes to the long run, and running in general. I feel your assesment of needing to train with longer runs is spot on. Train like you're training for a stand alone marathon...with caution. Shoot for a long run of 40k. Two would be better during the course of the training cycle. Try upping your general running milage. I think 5 days a week of running is best. 60k and above. Not all of it hard, of course, but your shooting for frequency. And of course this means some speed work, which can reek havoc on training in general...which is why I recommend caution.
I wish I had your bike time (maybe I would if I picked flat IM's)! The ammount of time you would have to put in to get to 5:20 or lower, could bring diminishing returns.
Then here is another thought: You may not be able to find those last 40 minutes. Yes You can probably improve, but after years of talking to and observing and doing some IM's as well as other endurance events I have found that each individual has a limit to how much work they can do, and that is beyound your control. You may be at yours now, but you won't know till you push it.
Go for it...but be aware of what may or may not come.

I hope I didn't miss it, but can you share your 13.1 run pace, 26.2 run pace or something close? Did you bonk on the run or do you have a slower pace? If you have 'ages' until your next race, I would consider working on run speed. Easy to say to do speed work, though, but that could change if you say you run 6min/miles and bonked. If you bonked you clearly would need to work on the run endurance. or maybe fuel.

or pick a course with a flat ride/run course--ahahhahahahah
I joke. I would kill for a 5:30 bike as I am hoping to skate in with a 6:30 this year (of course IMC is hilly so my own fault).

+1 to what Anton said about the run.
My training plans call for a 3 hour run max. I usually go for miles on that and hit 22 once and at least 20 once or twice. I am slower though so a faster runner could get 22 miles in during that 3 hours.

55+5:30+3:50+4=10:20
Okay, personally, I think you're just bragging, :)
but that's okay, you earned it.
Congratulations.
Just a nit: I get really grumpy when people don't know the difference between "lose" as in "to lose ten pounds" and "loose" as in "not tight", but maybe that's just me. I was a schoolteacher.
It just makes me think that the poster is unable to grasp concepts of training necessary to achieve goals so why bother telling them? Anyway..

You want to be 40 mins faster on 10:20 that's a 6.5% improvement. Maybe that's possible, it's hard to say without knowing more about you like say, your age, weight, training experience.
I surveyed some of your posts and it seems that you are quite experienced and must know a lot about race prep / training already. After all, nobody goes sub-11 by dumb luck!

Break it down.
6% of 55 mins is 3.55 mins
6% of 5:30 is 21.45mins
6% of 3:50 is 15mins

It looks like your run is soft 55min swim is an elite swim, 5:30 bike is top flite (depending on your age, but really good regardless) 3:50 marathon - not exciting unless you're old like me. :)

I'm guessing you wouldn't qualify for Boston in your AG, right?

So you have to figure out the run. Maybe it is as simple as "losing" 10lbs of bodyweight. There are calculations of how fast you can go at different bodyweights. Just for the sake of enlightenment Google it.

You want to go 9:40:00? Check out the splits on the IM website of your chosen race to see what 9:40:00 racers do in each leg.

Bottom line: At your level of ability, improving by 40 minutes is likely going to need a Professional Coach to workout exactly how YOU need to train to get 'er done.

Good Luck with "losing" those 40 minutes and making your goal,

PoC

I'm doing my first IM this fall, so I'm not super knowledgable. Doing what Anton had suggested I looked at Everyone who finished IMC in between 10:15 and 10:30 and they averaged 1:06 on the swim, 5:23 on the bike, 3:50 on the run, and about 6 min Transition, for a total average of 10:25.

Then I looked at the average for those finishing between 9:30 and 9:45. They averaged 0:59 on the swim, 5:12 on the bike, 3:25 on the run, and 4:30 in transition for a total of 9:41. Based on that I would say you need to improve both your bike and run.

Remarkable close to Anton's prediction :)
(yes I am very bored at work right now)

Also, comparing all the guys I know who have done both, I would say your Oly time is relatively slower than your IM time..... If that's the case, I would say speed is a limiter for you and you should take some time to develop the speed, then build into the endurance with that speed.

I would also look to make sure you have every bit of "free" speed on your bike that you can get. I.e. good fit, all the Aero toys, weightweight, etc

Good Luck!!!

FWIW, I haven't done an IM yet, but I'm going to chime in anyways. You are a good swimmer...chances of getting substantial improvement there are slim, but don't let it slide at all either. I think you would benefit mostly by doing some longer training runs, some med-long runs focused on speed, and biking more.

What stands out to me is that you can swim about 5-10mins slower than elites, your marathon is OK considering IM, and I may need to take a better look at the course, but I'm assuming its no IMLP, so 5:30 isn't exactly the top tier bike split.

That being said, biking more/longer/harder would also help greatly because biking can have beneficial effects on run speed not accounting for the fact that strengthening your bike leg will leave you more fresh for the run. I think by your fitness level (assumed) you should be able to take 20-30 minutes out of your run...that leaves 10-20 for the bike, also do-able unless your riding a ridiculous course

Let us know how it goes and if you make Kona...who you are...I'd love to be cheering you on in the future

I'm concerned about something here.

last November you posted this:

yet above, in this thread you wite that your swim split at IM is 55mins
"so my swim is probably ok, .."

Hell of an improvement in 7 months..
IMHO nobody who swims 3.84kms in a split of 55mins lacks sufficient knowledge of swim mechanics to ask this rather naive question. It doesn't add up for me.

Similarly, somebody who records a 10:20 IM time doesn't need to ask how to train in order to get sub-10, that inconsistency bothered me too, as I said above,
as did your question regarding Sprint training when you reported huge volumes of IM training and bricks in the same week..

You have no info on your profile, so what race did you record this 10:20 at?

Perhaps you could clear this up?

PoC