I’m looking for tips on further optimizing my TT position. BBS has my CdA at ~0.22 in my last couple 40ks. I’m on an old Cervelo P2 with a bunch of modifications. 1x, TriRig aero bars + front brake, brake cables running into top tube, good skinsuit / gloves / helmet.
I’m 6’1" & ~175lbs if that matters. Pics from last weekends 40k are below. Position is pretty similar in both, and power was almost completely flat all race. The bottom pic, my jersey is stuffed with ice socks and the top one has them all melted / a few miles before the finish. The ice socks kept me cool, but CdA was 0.01 higher before those melted, so that one hurt a bit.
I’ve seen posts that top TTers are down near 0.18 or so. If I got to 0.19, that would be ~1.5min improvement, which would be the equivalent of adding ~50w to my FTP.
Is getting down this low, for someone my size, possible?
My helmet can be a tucked a bit farther back, and my new socks slipped down my calves, but what else can I do? I can’t imagine those two make that big of a difference…
I almost think I need a frame with lower stack / longer reach, to get my position further dialed.
IME increasing reach is the most powerful tool most people have for decreasing drag. Now obviously don’t go out so far you’re squirrely.
Decreasing extension angle tends to work well for most people.
Tucking the helmet back makes many people lift their chin, I mean it’s worth testing yet I’m willing to bet some money that’s not your solution or a solution.
Aero socks are hit and miss. Brand A can be fastest for one person then for the next that same sock is dog poop.
Don’t worry on getting to a number. Worry that when you compare A to B your testing data is robust enough that you can answer the question is A or B faster.
Gloves: hit or miss. I’ve seen them do both
Velotoez booties - typically good, tbt I’ve tested the toe covers more than the booties though.
helmet - the aerohead is a great choice
suit - IDK this is always perplexing to me. I’ve seen off the rack test better than $1000+ custom bio racer suits.
Interesting you said increase stack or decrease angles.
When I look at my position, I would think I need to lower the front end (which could be decreasing stack or extending reach). Would you agree?
Otherwise, it sounds like you’re saying test, test, test and evaluate from there.
I haven’t found a good place to test using Chung method around my house, so I’ve been stuck on how to best test these positional changes…
Without testing you’re guessing.
You can achieve a bit lower position with extending reach and of course that also works with dropping stack. It depends which end you want to attack that from. Personally when testing, I usually go for reach first, ymmv.
The eval can be I made change A and feel 1000% better. if that’s the case you may not care about impact to CdA bc you’re more stabile on the bike, able to hold your position, stay aero later into corners/get aero faster out of corners/brake later into corners. Little things like that can make :01 here :02 there difference
The #1 question I ask when aero testing is “how’d that feel” or some variation on that.
I’d like to do Masters Nationals next year, and if I do that, I need to be UCI legal. My position is currently a tad bit long for that, so extending reach might not be an option.
Sounds like I really need to find a loop where I can test these types of changes.
I’d like to do Masters Nationals next year, and if I do that, I need to be UCI legal. My position is currently a tad bit long for that, so extending reach might not be an option.
Sounds like I really need to find a loop where I can test these types of changes.
Maybe the camera angles but your head position could be a few watts difference between the two pics
I’m often confused about the extension angle thing. Every pro and now every age grouper as a result have tilt. Comfort aside is it faster ? One would assume so. Companies like sync just to name a few make up their products based on bar tilt.
But I remember yourself and cyclenutsnz and even Kevin I think? Say that flatter forearms with moderate tilt, say 5 degrees, often tests faster…… I can only asssume that tilt tests fast at higher ‘pro’ speeds OR, tilt is purely for the ability on what it gets the rest of the body to do - that is drop the head down, relax into the shoulders etc.
I went from 14 to 7 degree tilt and feel fine at either. Perhaps prefer the latter. But I grew up when dead level bars were the thing…
Anyway I digress. OP I like ur position really and I know ur limited with regs, but I do agree on reach. And that’s nitpicking because it looks damn good eyeball test anyway
But I remember yourself and cyclenutsnz and even Kevin I think? Say that flatter forearms with moderate tilt, say 5 degrees, often tests faster…… I can only asssume that tilt tests fast at higher ‘pro’ speeds OR, tilt is purely for the ability on what it gets the rest of the body to do - that is drop the head down, relax into the shoulders etc.
That’s the subtle difference. Human bodies aren’t machines so sometimes you have to go with what’s faster in the aggregate rather than what is actually faster in principle. I found that tilted arms helps my upper body relax immensely but how much tilt that would allow this is still something I need to investigate. Brian implies this when he says ‘test extension angle’. I also found that my shrug and getting my arms closer together is easier if I run a compact position even though I’d agree with Brian that an angled cylinder is faster than a vertical one in principle.
I was running tubular zipp (I’m pretty sure) super 9 disc, with a GP 4000 glued on. It’s a 22 mm tire for the super narrow disc. Ran 115 psi
I ran zipp 808 w gp5000 / latex tubes. I debated going for faster tire, but chose this due to a bit more flat protection. Again, narrow. I ran 115 here too.
I was running tubular zipp (I’m pretty sure) super 9 disc, with a GP 4000 glued on. It’s a 22 mm tire for the super narrow disc. Ran 115 psi
I ran zipp 808 w gp5000 / latex tubes. I debated going for faster tire, but chose this due to a bit more flat protection. Again, narrow. I ran 115 here too.
I know I can do a bit better on tires next time
How good were the roads ? That is pretty high
At first I was intrigued by the low tire pressure claims, which after a lot of testing, led to a whole new appreciation of how important and especially cheap to find gains
90% of the course was very smooth pavement, but there were some stretches that felt almost like washboard / a little chipseal. I’ve raced before on VeloFlex tires on this course, but also have seen people flat on gp5k. It rained in the days leading up to the race so I was worried about debris on the course… but that turned out to not be the case.
I find the lower pressure on wider rims (like 303fc which I race with on road bike) is very fast m
But the old p2 requires very narrow rims / tires, so the pressure gets jacked up per the Silca calculator
It rained in the days leading up to the race so I was worried about debris on the course…
I always drive the course a day before and pick up all the debris. It’s boring and tedious but I love to do that so I know people and I can ride safely. Of course, I see some debris next day, but it’s still way safer than before.
I’d like to do Masters Nationals next year, and if I do that, I need to be UCI legal. My position is currently a tad bit long for that, so extending reach might not be an option.
Sounds like I really need to find a loop where I can test these types of changes.
Not true, unless you’re trying to set/certify a national record. I’m assuming you’re referring to USAC.
I was running tubular zipp (I’m pretty sure) super 9 disc, with a GP 4000 glued on. It’s a 22 mm tire for the super narrow disc. Ran 115 psi
I ran zipp 808 w gp5000 / latex tubes. I debated going for faster tire, but chose this due to a bit more flat protection. Again, narrow. I ran 115 here too.
I know I can do a bit better on tires next time
I was starting to think you are guilty of reading Sandy Scott’s excellent book, and that this was a Dave Viney Time Warp!
First, congrats on your current performance - toying with a 30 mph average over 25 miles at your age is great.
I posted the Ganna Hour Record picture to show the difference in hand positions. He’s also tall, and had to maintain that for one hour. It’s also what, IMHO, a lot of fast riders are doing.
I think High Hands, especially with the newer helmets that protrude forward from your face, plus maximum reach, are essentially helping to turn your whole upper body into a long horizontal cylinder…and the longer, the better, and the fewer the gaps, the better. It’s like the hull speed on large ships, the longer the waterline of the ship, the higher the number. As brilliant as Obree’s first position was, the Superman position was even better, because it made him longer. All this is strictly my opinion.
