Why not wear a bike jersey?

Well, here are possible cons: since it's looser, it may chafe more under the wetsuit and if you haven't tried running long in a bike jersey, you might get some nasty nipple chafe.

If it's cold, you're probably gonna be cold and wet on the bike whether you're wearing a tri top or cycling jersey, so I wouldn't worry about it not drying as fast.

Try it. Try it under a suit during OWS, and try doing a long run in it.

Biggest con is the added drag.  May not seem significant, but the extra effort adds up over 56 miles.  You will either be slower or use more energy.  The difference really is more than you seem to be giving it credit for. 

you have time after you swim. I would put it on then.

Is there any reason why you wouldn't simply throw on a bike jersey after you get out of the water? 

Use a full zip jersey and you shouldn't lose that much time putting it on...or taking it off if you don't want to run with it.

I'm assuming a few seconds won't matter to you...because if they did...you'd just deal with the sunburn. 

Train with it a few times and see if it works as well as you believe it will.

Run 21.1 km in your bike jeresy. If it feels good go for it.

My first HIM I wore a form-fitting bike jersey (which I had trained with); my second I wore a tri top.  Having done it both ways, here are my observations:

* The bike jersey was wicking, but of a slightly heavier fabric than the tri top so it held more sweat.  I wouldn't say it was heavy, but it wasn't as breezy as the tri top and felt kindof warm at the halfway point of the run.
* The bike jersey wasn't sleveless, which would have been nice on what turned out to be a very warm day.
* Collar on the bike jersey was slightly raised - didn't cause any chafing, but it also didn't go completely unnoticed on the run.
* The rear pockets on my tri top were tighter, so held less and were harder to reach into than the pockets on the bike jersey.
* I would never, ever have considered wearing a bike jersey under a wetsuit (because of the slightly thicker material).

I didn't hate wearing the bike jersey, but - given a choice - I'd do the tri top now.

I wore a bike jersey on many of my races, including at least one after I got a tri-top.  I've done sprints, an OLY, my HIM, and my IM with a bike jersey. 

It wasn't too hard to pull it on after the swim (that jersey is probably larger than I should wear). 

By putting it on after the swim, I wasn't cooling myself too much riding with a wet jersey (which is exactly what I did notice the OLY where I wore the tri-top the whole time). 

I used two bike jerseys (one solid blue, one solid yellow) on my 2-week backpacking trip in 2008.  The front zip, the partial collar, and the rear pockets worked out great for that. 

An excellent point, although if I get nipple chafe I may want to look into a different sports bra. 



I defer to the BT'ers that are engineers/scientifically oriented.  I'm sure you're right.  I suppose there's a reason why the cyclists in the Tour de France aren't wearing traditional bike jerseys during a time trial!





Oooh, snap!  The funny thing is, the few seconds do matter to me.  That's why I didn't even consider putting it on after the swim.  I suppose that's why I should heed AndrewMT's thoughts on the drag and simply suck it up. 


VitaminB and McFuzz: Thanks for the real-life perspective.  Guess I have plenty to obsess over think about before the race! 

Unless you are going for a podium spot go with comfort.  I am a burner and for HIMs and IMs I wear a bike jersey that fits snug for the ride and a tech t-shirt for the run.  The time lost in tansition is minimal and I will gladly give up a minute or two to avoid shoulder burns.  If it's a wetsuit swim and the weather is warm wear the jersey under your wetsuit; if the weather is cold don't wear it under the wetsuit and dry off quickly and throw it on.

What ever you go with go for what works best for you.  8 months gives you plenty of time to try out different options.

My biggest reason is that I don't find bike jersey's comfy to run in.  For my recent IM, I cycled in a bike jersey then did a quick change in Transition.

That is exactly what I did... easy to put on after swim... no issues on the run... preloaded the pockets with GU packets... worked like a champ... I trained that way and hence I raced that way...

If the weather is cold enough to make be consider something other than a tri top I'm going with a full sleeve zip up after I get out of the water. I don't see that much difference between a bike jersey and a tri top especially if they are both wet to begin with. If you are worried about sun burn why not just use sunscreen.

A few seconds here, a few seconds there...it all adds up to very significant time!

I did a sprint race a couple of years ago using a bike jersey.  Never again.  It dried out fine after the swim, and was great on the bike.  But the bunched elastic sleeves ended up causing abrasions on my upper arms after running due to the back-and-forth swinging - and that was just 3.1. I would hate to run 13.1 - I think I would end up sawing off my arm!

As someone who burns easily, and uses a lot of sunscreen, there is nothing quite like the protection of sleeves over shoulders to prevent the burn. A missed spot can be painful for days and I would personally rather avoid burning in whatever way possible, which may include putting something on with sleeves.

Note - I haven't done anything longer than a sprint where I didn't worry about sunscreen, but would definitely be taking sleeves into consideration on longer course action. 

I burn easily and got fried twice during races this summer.    I'm thinking of trying out this next year:

http://www.desotosport.com/products/product.asp?Category=messentials&ProdID=LST1 

I've done races wearing a bike jersey. Early in my tri life wore  tight fitting sleeveless bike jersey most races.

First IM I wore bike jersey on bike and changed to tri top for run.

You can find tri tops with 3 pockets in back like bike jerseys. Check out DeSoto and the men's tri tops with 3 pockets have nice pockets.

Bike jersey doesn't fit as tight and cause more drag & chaffing &, fabric can be same or different to tri tops so may dry well or may not need to test it out.

I don't think I'd wear short sleeve bike jersey under my wetsuit due to potential to chafe and changing when wet wastes time.

Worrying about the little details now, spend the time looking on line finding a tri top with 3 pockets and you will be comfortable racing in. Tight fitting clothes is the best bang for your buck to reduce drag and be faster on the bike in front of wheels, aerohelmets and all that.

You have to go with comfort and convenience. 

The response earlier that said there would be a significant aero disadvantage is flat out wrong.  If you're at the level where your next aero again is from the top you wear, you wouldn't be asking this question.

When I did my first half ironman I got fully changed into cycling gear (shorts and cycling top) and then running gear (shorts and tee-shirt).  It added four minutes to my time but I'll never know how much time it saved in making me perfectly comfortable and free of any discomfort for the entitiry of the event.  I did the same in my first Ironman.

In my most recent Ironman I went tri-suit the whole way and it bothered my mentally having to rely on aid stations for nutrition and not being as comfortable as a fresh shirt on the run - so next summer I will probably be going back to full kit change.  I'm a 12.5 hour ironman and 6hour HIM if that makes any difference

Aero advantage applies to everyone, experienced or no.  You may not care about the time loss, but the time loss still exists.  My statement was absolutely correct, you may just choose not to apply it because you're worried about being comfortable. 

The OP was asking about saving a few seconds in transition, so time is obviously important.  We're still talking about racing, so time is obviously important.  If comfort and convenience were our primary concern, we'd still be at home on the couch. 

We'll have to agree to disagree.  I've just watched Jodie Swallow become World Champion without deep rimmed wheel, an aero helmet and a relaxed riding position because comfort is more important and she's coached by Brett Sutton.  Chrissie Wellington - fastest athlete of all time, carries additional puncture repair equipment to give her peace of mind.

You implied that the time loss is significant or "a lot more than you give it credit for" - I think it will be less than 20 seconds over 56miles and the time gain from additional comfort will run into minutes.

I believe that small time gains, added up here and there, become very significant time.  I agree that it's important to be in a relatively comfortable position on the bike, but there's no reason you can't be comfortable in a tri-top.  At the end of the day, if you're racing correctly, you have to learn to deal with discomfort and pain. 

Comparing AGers to Pros is absurd.  Chrissie Wellington can crush most the field on a hybrid bike wearing a parachute.  The same doesn't apply to most of us and we need the additional advantages that can be gained by paying attention to the details.  I'm not sure what your point is by bringing up Sutton, as he doesn't really lend any credibility to his athletes. 

Bottom line is that the OP stated: "a few seconds matter to me"!!!  ?