I’ve managed to reach a position which I’m going to hold on to, so thanks everyone for the input on my previous posts.
Last event, finished 6th, less than a minute off the winner in a 10m TT, so it feels like I’m doing something right.
I’m gonna keep working on my form, discovering new courses, attempt PBs and hopefully be in a position to upgrade the frame next season.
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Not that you asked, but looking at the picture:-
There looks like a few wrinkles above your ankle in the aero socks… could you pull them up more & save a fraction of a Watt.
Have you tried stacking your hands on top of each other for at least the straight flat bits it presents a slightly smaller profile to the first contact point with the wind.
Pin your number slightly lower down, there is a small lip for the air to grab & slow you down in the picture (or get a nopinz pocket fitted).
Otherwise looking good.
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No worries, fair comments and appreciated!
I’ve been more worried with the bigger picture recently but it is definitely time to look at the small detail too.
I’ll try to get the aero sleeve sorted.
I’m practising in training the stacked hands, but since I’ve not really ridden much on the tt bike I still feel safer just holding onto extensions firmly. Confidence will surely come with time.
Fair comment on the number. I plan to have the nopinz pocket fitted to the skinsuit once I have a break from events which happen to be every weekend till at least end of May.
Thanks! 
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Tires
Anyone still running tubulars (sew-ups)? I know tubeless is the way to go, but a few of us here are still running HED Stinger Disk + Stinger 9 race day wheels. This stuff is too expensive to replace just to save a few watts and frankly, for the amateur racer is just fine.
For a while, the Bontrager tubulars were the best choice. Then those went away and we mostly switched to Zipp Tangente SL Speed tires. It looks like those have gone away.
Given that tubulars are an endangered species, seems like for TT racing the current best pick would be the Vittoria Corsa Speed G2.0 I have a feeling these are the same casing as the Zipp but with Vittoria’s latest rubber.
I also run Conti TT Grand Prix tubulars on a hill climb bike. But they tend to be a bit narrow and don’t sit as well on the Stingers.
So for guys running tubulars - any other suggestions and have I missed any new tires worth taking a look at?
In much the same boat, current Corima disc wheel is for tubs. Too expensive to replace with a tubless disc wheel. I run a tubless HED on the front.
I’ve run a Vittoria Corsa Speed on that wheel (same but TLR version on the front) for two seasons now without problems, open events and local evening league TT’s on typical bad UK roads., it’s been good and reliable.
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Finally got a decent picture of the latest position in the wild with TT season getting underway. Good to see that it isn’t too far off the position on the turbo but need to work on keeping the head tucked.
Any feedback on position welcome!
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If you rotate your hips forward, and then lower your front end, you’d have a fantastic position. You have good angles all around, but you are sitting more on your sit bones. Rotate forward, lower the front and you’ll be killing it.
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I do NOT think Tubulars are a dying breed. However I have swapped from narrow tubs to wider clinchers ()that happen to be tubeless) simply because of the roads I TT on and to give my undercarriage some TLC. The ride is definitely smoother.
I used Podium TTs, front last three years: found them pretty good. However on the rear I stripped tread when braking once and was disappointed. so for longer TTs I used Conti comps. I was going to swap to Vittoruia corsa speeds and corsa (front/rear) before I went tubeless. There was an Aerocoach Instagram post out yesterday that suggests a well glued tub (not taped on) in Corsa speed form is as fast as any tubeless.
Choice of Tub tyre much depends on
- your tolerance for puncture risk vs absolute speed
- length of race 10mTT vs 100 or 12hr
- How much you are willing to carry as a spares vs walking home down a DC.
Note Butyl tubs (conti) can take their sealant which is very good (I hammered a 2" brad nail into mine as a test and it sealed after two rotations). Latex (vittoria) do not recommend a sealant, but using their pitstop in the evbent of a puncture. (Which is a pain to try and fit into the valve gap of a rear disc.)
My 2-penneth.
Much appreciated. For some reason I always seem to fall back into tensing my mid/upper back and ending up hunched up. Had a play around tonight; took the 20mm spacer out and tried to work on flattening the back and rotating the hips. Surprised at the difference side by side, some work to do to see how sustainable it is but it doesn’t feel much different.
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Can someone offer some feedback for sizing of my first TT bike? What should I be interested in while viewing and testing the bike in a short period of time?
The bike in question is a large / 56cm 2017 Scott Plasma and I’m 183cm tall. I usually ride a 58cm road bike (Cannondale SuperSix 2015 and Trek Emonda 2021).
When you say “rotate your hips forward” how does one do that in practice? Asking for a friend with a large disparity between road bike and TT power 
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Oh, MUCH better!!!
You just hit a key point…if you rotate your hips, it shouldn’t feel much different. All your angles essentially stay the same, you just rotate it all forward so getting lower doesn’t mean more uncomfortable.
I like to think of having a dial on the side of your hip and you just rotate that dial forward, around the bottom bracket. Another way to think of it is that you want to shift some of your weight from your sit bones towards your more…gentle parts. 
A snub-nosed saddle will help in relieving any pressure on your gentler parts when you rotate.
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Is anybody using mywindsock to watch changes in CdA?
Not sure if I should take it any seriously, but I’ve noticed changes in CdA values which sort of correlate well to how I perceived conditions on the day vs power vs time.
It has been anywhere from 0.25 to 0.21 now, which has been constant over a few events to within 0.00x when using my current setup.
Also, I’m aware that some riders can reach ridiculous CdA values as low as 0.16, but realistically, what would be a target CdA for someone of a rather big body size (191cm tall/90kgs), without going crazy on windtunnel time and equipment?
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(Not associated with the service). Probably many of you know or use it but if not it seems a quite impressive service for modeling. CdA calculations are free and tests that seems exactly like insycd for 25 eur. Tests are for one month so you can track training block improvements. They have also some nice training recommendation based on the tests:
https://aerotune.com/
In Scientific Triathlon Podcast was an interview with one of the founders. Sorry if I am posting something obvious but maybe someone will find it useful.
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Hi, check SQLab.com, a german company with an unusual approach to saddle design for ITT.
Good luck.
I’m 191 and 86 and am 0.19X in most races on mywindsock just as a point of reference.
I’m sure I could go lower if I could get repeatable results with the chung method but I haven’t been able to do that (yet)
Joe
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I use the free version of www.mywindsock.com
I’ve no idea how accurate it is but I have my Cda set 2/3 of the way between the default for sitting upright on a TT bike and on the poles that gives me 0.205. I think if you subscribe it will calculate your Cda based on the weather, weight, power and speed (and perhaps a few other factors).
OT it always amazes me how folk who put out far less power than me aren’t far off time wise as they hold a much better Cda. Even my own rides will vary significantly if I get freaked out and sit up. Thankfully I didn’t on Saturday 
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I’ve only used reverse-engineering on bestbikesplit, but my CDA is coming out close to your’s, @Joe.
I’d like to do some proper testing, but there isn’t any happening right now in the UK (I don’t think?)
@KamilW - given your power, I guess your CDA has a little room for improvement still, but its hard to do this from photos; and your current CDA certainly isn’t bad! Its just that you are likely to see more % improvement in CDA than in FTP, if your FTP is up at 370, 380W.
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@Joe This is what I wanted to hear.
Hopefully, I will also find the time and a right place to test the chung method at some point soon.
@HLaB I think this is what annoys me a little bit at the moment and makes me look into ways of improving the CdA more and more.
@GregElwell Why do you think there is a little room for improvement in the CdA department?
When it comes to power this is what I’m thinking too. I’m unlikely to get much more out, so, I’ll put more focus on reducing the CdA - which can hopefully happen.
However, I’m still trying to figure out how to consistently come in a good form to races.
My 10m TTs can have same avg power as 25m TTs, and on occasions I will produce 20mins in regions of 390-400w, which I would like to see week in and out.
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Simply put, if Joe and I (and I am sure others) are well below 0.2 CDA, and we’re similar height (OK, I’m a little shorter at 185), then that’s a good target for you (in terms of your CDA). Some of the other guys we are racing against must have CDAs around 0.18 or below, because I have raced against them, and I can see their power numbers.
I have no idea how many folks had aero testing in order to get down to those figures. I haven’t (yet) and as a result, I am sure I have a lot more CDA gains to find. But I am not making anything like your power numbers. So there’s an opportunity for me there! 
In terms of chasing aero, there’s a lot of great advice up-thread covering more general points - back shape, head position, making the helmet work, arm position and comfort too. Beyond this, though, I think it gets quite individual, and so finding even simple ways to test is really important.
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