5K PB. Fastest 5K ramp ever? Whats my tri sprint pace?

Nice!  Sounds like you have a lot of potential!

You will notice that the improvement will taper as your times get faster.  When that taper happens is really individual and depends on a lot of factors.

For example, if you set out to lose weight and that's already done, you won't continue to improve based on lower body weight, which is measurable.

In response to your second question- In my experience, the 5k run leg in a sprint tri is 30 seconds to a minute slower than a standalone 5k.  However, this is also dependent on lots of factors... primarily whether you paced your swim and bike properly.

I found the quick gains like that in 5k speed are from learning to hurt so to say. When you first start out you only *think* you are running your hardest yet you learn to push yourself even harder. I myself dropped from a 38:30 5k to a 25:16 in under a year. (Also dropped 110 lbs in that time which probably didn't hurt)

The tri effecting your run speed is going to depend on how hard you push during the swim and bike. Your brick runs like you did should give you an idea of your pace off the bike.

So nope I am NOT on the fastest ramp ever, you have it! 13 minutes in under 12 months is awesome my friend!!!

I need to try and ride then run harder. Today I just jogged, probably just over 30 minutes. This was my first "real" brick of the season, need to get more in before my first sprint next month. I have done a few bike trainer to treadmill bricks but it isnt the same.

Mind if I ask what you did to get such gargantuan improvements so quickly?  Weight loss?  Intervals?  A visit to Lance Armstrong's "suppliers"?

I was roughly on par with your times back in September / October -- suffice it to say we've diverged a bit since then 

I agree, and I would say the other big factor (maybe even more than pacing), is simply your swim and bike fitness.  If properly pacing your swim and bike means that you don't even start the run till 70 minutes after the race started...you're likely going to be a lot less fresh than if a properly paced swim and bike had you starting the run 45 minutes after the race started. 

I have been steadily loosing weight the whole time so kinda a moving target. I did start doing intervals, tempo, and hills. Ex. On a 3 mile run I many run easy, then speed up to a 5k or faster pace for .25 miles, slow down at mile 2 speed up at 2.75, etc. Hills sprints on treadmill, hate em but they help. Tempo even at longer distances mostly 3-6 miles. Speed up a bit every mile.

Also have done the classic 4-6 miles which warm up, fast couple miles, cool down.

I am starting to ramp up miles for a 1/2 marathon and 70.3 later in the summer. Dont know if this will work my short speed, hope not!

I was pretty disappointed with my 5k during my first sprint tri. I had never run after a bike ride and my legs were just not having it. My time was 2 minutes slower than my open 5k time, and I felt like I should be able to run faster. Since then, I have improved my open 5k by about a minute, and during a practice tri, got within 30 seconds of that time. 

My suggestion is too start practicing that now.

Totall depends on how hard you work the bike (to a lesser extent the swim also).  Last year I PR'd my 5K at 20:32 (6:37 pace) but I normally run 7:20-7:30 for 5K in tri's but that's because I go hard on the bike (22-23 mph).  But last year I did a sprint where it rained so I went very conservative on the bike (19 mph) and ran 21:18 for the 5K (6:52 pace).

With regards to fast 5K ramps I went from the couch to a 22:34 5K in one year.  In May 2008 I weighed 246 lbs, ran the 5K a year later at 195 lbs (at 42 years of age).  I did a lot of swimming that first year and actually didn't start running until about 7 months before the 5K, wanted to shed some weight off first.  Then when I started running I went to spin class, then started bricks even before I even thought about tri'ing.

Your progess is excellent, keep up the good work!

1. I didn't read the whole thread very carefully, but it also depnds on your age.  The younger you are - down to about late teens or so I'd say - the better and faster ones improvement.  Regardless of age though, your improvement given consistent training will flatten out as you approach your "limit".

2. My 5k sprint pace is about 10 to 15 seconds slower than my open 5k pace on a comparable course. 

Nice improvement regardless!