Is there much of an aerodynamic cost to stuffing the rear pockets of a jersey / race top with what you need for a race? I try to keep my bike pretty clean (that, and I’m tired of stuff falling or getting shaken loose mid-race, no matter how tightly I strap it on …), so instead of a bento box and all sorts of stuff strapped on the frame and seat, I normally just put a CO2 and lever, 4 clif bars and a gel flask in the back of a tight-fitting jersey. Good? Bad? better or worse than loading down the bike? or is it too insignificant to really make a difference?
glad you asked. i’m also very interested in answers to this question. i read somewhere that loading up your bike behind your saddle (with hydration systems and saddle bags) impacts aerodynamics negatively. i still use a bento box and the profile design bottle up front. i’d like to use a small saddle bag for my spare tube and a C02 but not sure if i should stuff it in my jersey like you do…
if you have more than one pocket in your jersey you will finish in 13:32. If you don’t have pockets you will finish in 13:31. Its the ironman!! I say worry less about pockets and train more.
Woohoo…
A little sanity in the sea of aero silliness… “I finally got my 37 pound P2 completely aero”
Ok, now that you have provided this helpfull advise, why not answer the question asked, if you know.
Ok, now that you have provided this helpfull advise, why not answer the question asked, if you know.
I believe he did. The general gist of his post was that unless you are seconds away from Kona/podium, the time difference is negligible enough as to be insignificant. If you go 11:01:22 when your goal was to break 11:00, then you can always blame it on the aerodynamic drag of a bulky jersey.
John
ok, so the answer is that the aerodynamic cost of a pocket is 1 minute over 112 miles for an athlete that expects to finish between 11 and 13 hours.
yeah sorry for the sarcasim. I agree with devlin. Bottom line is when your doing an ironman you are in and out of your aero position a lot whether it be aid stations, fatigue, reaching for water/food, or taking a dump. So the pockets in a jersey isn’t going to mean squat. My advice to him is wear or pack whatever is comfortable and easy to access, and to train harder so he is able to stay in the aero position for as long as possible.
Thanks Trigeekhb and Devlin. All other thinkg being equal, would you carry “stuff” in a bento box, behind your seat or in a pocket? Does it matter?
whatever you feel comfortable with. IMHO there will be no time loss with any of those options. Train how you race.
I’m the same…I can’t stand attaching anything to my bike/frame, hence no bento box, saddle bag, etc. It probably is too insignificant to make a difference (I’ll wait for Tom A & AC to prove me otherwise) but clean, tidy and aesthetically-pleasing bikes are much nicer to ride :). I would’ve thought anything reasonably “flat” like the clif bars would be sweet back there and have zero aero penalty. Why not bundle up the the C02 inflator & lever with your spare? You didn’t mention carrying one, how bout taping a tube neatly & tightly under the saddle? For me I had a gel flask tucked down the front of my top (out of the wind, I think?), then an open clif bar and about 8 half powerbars in my rear pockets. I don’t think it harms my IM bike split…
Why is it that whenever somebody asks a question about aerodynamics that somebody else will inevitably chime in that the effect is negligible and that they had better “work on their training” instead?
The OP’s question is legitimate and worthy of an educated response. Sadly, I don’t know the answer, but I too am hoping that someone more knowledgeable than I can give some real figures about the cost of stuffing pockets vs bento boxes vs behind-the-seat bags, etc.
It really doesn’t matter if a Kona slot is on the line, or you’re trying to smack down your buddy with a 13:43:56 IM, or whatever. Some of us actually enjoy shaving theoretical seconds on our tri times. And this enjoyment is independent of our training time, diet, weight, coaching, or anything else that the naysayers proclaim we should focus on instead.
Have you ever raced an IM MOP_Mike? If you have you know that staying in the aero position the whole time is extremely hard. My suggestion was to not worry so much about pockets in a jersey and to use whatever fueling and/or packing method he feels comfortable with, and to train on staying in the aero position longer.
If he is concerned about drag, he obviously cares about his time as we all do. And I feel that staying in the aero position longer and using whatever method he feels comfortable with will be the greatest time saved.
Have you ever raced an IM MOP_Mike? If you have you know that staying in the aero position the whole time is extremely hard. My suggestion was to not worry so much about pockets in a jersey and to use whatever fueling and/or packing method he feels comfortable with, and to train on staying in the aero position longer.
If he is concerned about drag, he obviously cares about his time as we all do. And I feel that staying in the aero position longer and using whatever method he feels comfortable with will be the greatest time saved.
Yes. IMCDA '07, as well as numerous halves and two ITU long course races – certainly not as much experience (or speed) as many posters here. But this is totally irrelevant to the OP’s question.
Training to stay in the aero position is totally independent of the aero cost of stuffed jersey pockets. It also states the obvious and avoids the OP’s original question.
Of course there is a benefit to staying in the aero position longer. That’s not what the OP asked.
so, how did I fail to answer the question?
I normally just put a CO2 and lever, 4 clif bars and a gel flask in the back of a tight-fitting jersey. Good? Bad? better or worse than loading down the bike?
Ok, so your opinion is that the aero cost of the stuffed pockets is irrelevant. Can you point to any data to back that up? Is it “good, bad, better or worse” than the alternatives that the OP asked about?
PM sent mike. I don’t wanna hijack this guys thread any longer.
If you have you know that staying in the aero position the whole time is extremely hard…and to train on staying in the aero position longer…And I feel that staying in the aero position longer…
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Sorry to edit your reply short, but your insistence on this point raises an eyebrow. Have you ever actually seen the absolute fastest guys in our sport ride their bikes in a race? Try hunting down the Kona race footage from 2005 & 2006 (the whole bike legs, all 4+ hours of them that used be be available on the IMLive site with the entire swim & runs legs too) and just see how often these guys & girls get out of their “aero position”. Head down, tail up is not the only way to ride a bike, although you’d be hard pressed to suggest otherwise here on ST. True they are standing to keep speed up (up inclines, over rollers, while stretching, etc) and not because their positioning/conditioning is poor, but you might be surpised to see how often they get out of position.
Dude it is their are so so many variables. If you believe M.I.T. Gloves cause more time loss than any clothing! In the real world, due you think wearing gloves caused you to lose positions? Asfar as a minute faster at 13hrs (I am not far from that) agin so many variables…just be in better shape.
The OP’s question is legitimate and worthy of an educated response.
Mike,
I don’t know how educated my response is - certainly has a decent amount of experience behind it. I never did and still don’t like having stuff all over the bike - it has to negativly effect aerodynamics( if minimally), but it also effects how the bike handles - all that stuff mounted high up on the bike really upsets the natural center of gravity of the bike and can make a lot of noise rattling around. That’s why my personal preference was to carry as much as I could in my race jersey pockets. It was easily accessable. I never lost any of it during a race. Never thought much about the aero penalties. I figured it was held in tight and it was rounded. How bad could it be?
In an IM I would start out with two bottles on the frame - and 5 energy bars in my back pocket. Spare and C02 was strapped under the seat and almost invisible. I did 9 IM races this way and never had a problem.