Really need advice on whether i can do the Oly i registered for in Sept

To get to 25 miles, you ought to use easier gears, and get that cadence into the 90-95 range.  I think that would also make your legs feel fresher for the run.

If you do the race, you ought to take it VERY EASY on the bike.  We're talking 15-16 MPH here.

You don't have any training logged, so it is hard to say do it, or not, so I won't.  The guideline I've seen is that you ought to be able to bike for 2-2.5 hours and run for 1.5. 

You've got 6 weeks so make the best of them. 

Get out for a "long ride" every week.  Initially, this may be 16-18 miles, but it should be 25 miles by September 14 to give you a week to "taper."  If you're training by perceived exertion, keep these rides around 5-6 (an effort you can sustain for 90 minutes).  If by heart-rate, keep them in Z2. 

Yes, increase your long weekly ride, runs, swims but stay in the correct zone for HR or RPE, don't go to hard.  That 20 miles you just did on the bike is a great start, next time try and maintain the same pace the whole ride.  You can build fitness up to 10 days beforehand then it taper time. So in the next 4 weeks do something like this (10% increases) for your weekly long one:

• Week 1 - 20 mi
  
• Week 2 - 22 mi
  
• Week 3 - 24.2 mi
• Week 4 - 26.6 mi
  

Better to deal with the work load now so you can taper and enjoy the race! Be realistic about the bike since its your 1st Oly and your still building your base.  I went to hard on an MTB for my 1st Oly bike and it killed me on the run.  I did it 6 weeks after I did my 1st Sprint, wasn't in true Oly shape for it per say, but it taught me what being in Oly shape meant for the next year! 

Start using your logs, it's a great tool to be able to go back and look at your progress over time.  Not sure if your following a training plan or not either. 

I'm with your wife on this. You spent the money on an entry fee, have been spending tons (hopefully) of time away from home training, and now you want to drop out because you're afraid you won't be fast enough?

Unless you are injured, or have some sort of crisis at the last minute, you should plan to do the race.  Focus your training on your weak area, and plan accordingly for next year. 

first off, let me say that i have been training.   no i haven't logged much of my training, but i've been riding 2 times a week (i now know this is an issue), running 3, and swimming 3.   

my fitness level is relatively decent.   i've run up to 8 miles thus far at a 9 minute pace.    i've been swimming 3 times a week basically because i had to teach myself TI over the course of 3 months.    since mid May, i've been averaging 5 or 6 days of training a week.   where i am at right now is only because i've busted my butt over that time.   in May i couldn't barely run a mile without dying....now i can do 6 with plenty of reserve.

i guess i need to expect to just get out and do the 20+ mile rides and stay in a slower pace than i did today for my 15.   i realize 20-25 miles is short for bike rides, but it is long if you've only ridden a couple days a week for a couple months.

Every single one of us had to start out just like you are now!  Great job at the progress you've made so far.

~ 2.5 years after I started out I did a HIM, MiamiMan, wasn't planning on it.  In fact when I was stating out I told others 'no way that's not for me'.  But my friend / business partner signed up in April of 06 and said that we'd make it a "business" trip!  I figured in 6 months I could do it for the experience and sure did learn a lot over that time.

ok ok , i knew you guys would be the voice of reason.

i think my issue is that i need to swallow my pride and realize this is just to set a base for future races.   i just hate the idea of perhaps taking it a bit easy on the bike to help with the run.

i guess i need to just maybe stop looking at my mph and just do what it takes to get some miles in.