what do you want to see tested? (wind tunnel)
 

Starting to put together my next trip to the tunnel. I've got a fairly extensive list of things I'm going to test (mostly clothes/helmets) but depending on the how fast we get through things (should be pretty fast as I will not be testing at many yaw sweeps) I might have some time to get some other stuff in, if anyone has a good idea I'll try to fit it in!

Some thoughts / info before you make requests
The majority will be tested in pursuit setup (aerobars) but I'm hoping if time allows to test a few runs with drop bars

- Wheels - I've got maybe two wheels I'm going to test (front) a 5 spoke and a disc, and the reason for that is I tested the 5 spoke last time I was at the tunnel, but didn't have a "real" (we taped up a spoked wheel as a proxy) disc, so I'd like that data point to compare... that said, testing wheels takes a long time (lots of work to change them out on the rig) so I probably will not test any more after the disc goes on.
- Helmets - Plan is to test a few "top end" helmets against my aerohead ultimate (I'll also be testing the aerohead without the visor) - currently planning on the POC tempor, Lazer Wasp/Victor, Kask Mistral. I've tested a lot of helmets in the past, can't think of any other high end one's I've not tested.
- Clothes - I plan on going through about 5 higher end skinsuits, two pair of shoes, and a pair or two of socks/shoe covers. The shoes/covers/socks will be towards the very end because it's lower impact most likely, so as time allows.
- Position - I pretty well like where my position is at currently, but I may try a few different things towards the beginning of my runs just to see if there is a different avenue I could go down.

I *might* also have access to an on track aero sensor to play with the same few days... may be able to get some verification data rl vs. tunnel. (and might have time to test more out there)

Anyone have any suggestions/requests?

What 5 spoke is it? Might be interesting to do a Zipp 808 to satisfy Carleton.

unfortunately not an iO but an iO clone.

fwiw if anyone wants to make comparisons, the difference between it and a HED3 was .0019 (in favor of the H3) plenty of comparisons between H3's and 808's out there. (both 3 and 5 spoke with 19mm tires)

I'm curious to see what the real advantage of a front disc is.

Around 1 second per km...

Are you planning to vary your cadence - especially during wheel testing?

You might consider using Design of Experiments (DOE) so you can have two are more variables tested at the same time.

Cadence will just be steady. It's possible that on longer runs (you basically just take readings for 2-4 runs, but alltogether) I could vary cadence... but more than anything it's a matter of sunken cost and would be the last run of the day most likely. (just to eat the final few minutes and, more importantly, to verify that I'm not moving/squirming and tainting the results)

Every run is going to cost roughly $25-$30 (small changes with a runner from tunnel to control room) and so it's easy to see how you just have to remove as many variables as you can and go with it.

Anything that takes any extra time starts eating into your $$$, so clothing changes (because I have to get out of the tunnel, change into a skinsuit and then get back in) cost more... doing something like testing 1 cadence vs. another cadence would basically mean testing 1 thing would cost $50-60. Testing wheels (because the tunnel operator is the only person who can touch the "rig" / change the wheel) costs more like triple anything else, which is why I'm reluctant to do more than one or possibly 2 changes.

Jeez I hope not. I rode one for a kilo *once* and the difference seemed much more marginal than that. I'm hoping this tests justifies my inability to afford to buy a front disc!

Roughly about 1s per km, but that's at a sustained speed. For a SS race, like the kilo or 500, it will be less, as you spend a considerable part of the race getting up to speed, where the aero benefit will be lower. In a Kilo, it will be finding the balance between weight and cda with a front wheel.

If you can find a front disc that is as light as a spoked deep dish or a foil wheel, and is stiff ENOUGH, that would be your holy grail.

My personal opitnion for a front wheel would be a trispoke if it's sufficiently stiff for your needs. Barring that, a deep dish wheel with lower spoke count, although it would probably be just as fast as the trispoke. For a heavier guy like me, I would steer clear from the original trispoke (HED, Specialized) as i found them flexy, especially on steeper tracks.

Dang. At this point one second off my kilo would put me in "ok now I can quit" territory as far as goal times achieved!

Sorry, steady state gains Babypuke... Time gain was posted years ago by Alex Simmons compared to old Shamal /808's and not from my testing.

When I went into my local tunnel it was with the TT bike. Dabbled with some curiosity tests at the end of my session. Bottle position, clothing (skins was a quick pull on to test full legging material if aero benefit) and a few others just to use up my last minutes.

Yes.

Unfortunately, I don’t have my 808’s anymore. Sold them to a fixie kid (my world has come full circle).

I have some 33cm Alpina and 34cm Nitto bars if you want to test those.

I’m on my mobile phone now and haven’t read the entire thread.

I’m happy to send a few bucks to help offset the expenses.

A2 does have a number of wheels to test (although I'm not sure on specifics. An 808 is likely though. I do know they don't have any track specific wheels like an iO)

Some things to think of (for everyone, not just @carleton) is say I test 33cm Alpina's and 34cm Nittos. How would you want them tested? Rider off the bike? Rider on bike? How would we feasibly account for the difference in reach and drop between two sets of bars? If you don't account for it, then the 1cm difference will be swallowed up in the rider's position changing.
Lets say I borrow an iO and an 808. What tyres will make the test fair? An iO (besides the Rio) wants a narrow tyre, like 19mm... but that won't match the profile on a Firecrest or newer 808. What if the wheel I borrow already has a tyre glued to it, but not the optimal one? Or the 808 I borrow is a clincher?

Just some things to consider.

Thank you for the offer as well @carleton. I'm not sure if the interest is there as a whole... but it's not unprecedented to have a sort of crowdfunded tunnel session. link
The problem (morally at least, to me) is that if I took anyone's money, it would have to be a bigger *scope* project than just tacking it on to the end of my own personal testing. To control so many variables would take a bigger team than just me, the tunnel operator and my handler/eyes/runner.
Triathlon world there is that kind of interest to support a project like that, not sure about the track world though.

Well, since this isn't a proper scientific study that's gonna be peer-reviewed, I think if you designed a basic test for every scenario you want to consider, I think the audience will be pleased. Hell, designing a test is a significant exercise in and of itself.

Basically:
- Don't overthink it.
- Don't make work for yourself.
- It's your time, money, and energy do what you think is best...and feasible.

Also, if you did design a series of tests in order to be peer reviewed and accepted, you should get paid in either cash or college credit. I've always wondered why this hasn't been tackled by some Masters or Ph.D. candidate.

When Lee Childers, Ph.D. was still a candidate at Georgia Tech and a regular at DLV, he gave this presentation that I attended:

https://math.gatech.edu/seminars-col...lders-20100120

Not sure if it was his thesis or not (not sure how that works). It was a great presentation, though.

Ha...just found the PDF of the presentation.

I would really be interested in noting the wind resistance and aero effects in the difference
of riding in "street " apparel vs a cycling kit.

Generally see a lot of riders with high end equipment, weight conscious and aero, wearing
non-form fitting , floppy clothing for cycling.
Disc wheels and carbon bits......

Have been curious for many years on this one.
rusty

I hate making suggestions on stuff like this as the person probably knows 10000x what I do about it.

But, I'm genuinely curious in the balance of CRR and aero between a 23mm on front versus a 19mm.

I'm not in a budget to afford the newer stuff and wonder what I throw away in CRR and practically applying power comfortably on a 19 versus what I could with a 23.

Not sure how you'd objectively do that though given your swap on the disc wheel and wheel swaps being a limiting factor.

Just a curiosity I've always had.

In terms of something easier to test? I've also wondered whether stacked hands is only a "high hands" trick or could also work out with lower hands.

Even if I think I ride with higher hands, it's not even close to what the modern fits are doing. If the road is smooth for a while I'll stack em. But wonder if it is worth it or not since I'm not "that high".

If that happens, give a shout out. I have a few ideas.

quite a few tunnel tests / info on clothing comparing "standard kit" to skinsuits. From normal cut bibs/jersey to a good skinsuit you're looking at 90-150sec / 40k. Sort of depends and ebb/flows, as regular "kit" has gotten more "racy/aero" over the last few years... but also the top end skinsuits have gotten faster.

On a super smooth track there isn't a ton of balance between 19 and 23. It's heavily in favor of the narrowest tyre that reasonably fits your rim, since you want pressure to be insanely high anyways. On less ideal conditions it just really depends. Follow Josh's (Silca) advice for the most part and it should land you at least in good shape.

As for hands... I've tested it in the past (twice) in different trips and different positions. Stacking hands was never best in any of my positions. Possibly you need to almost stack the forearm on top of each other as well... or maybe it just looked cool when Zabriskie/Wiggo did it and we all assumed it was fast.

It's something I will probably look at (again) if I've got time.