Let's See Your Time Trial bike

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CrankAddictsRich
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by CrankAddictsRich

Have you guys seen this thing? Looks like a good tool for more in depth Chung method testing...

Aeropod
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by Weenie


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CrankAddictsRich
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by CrankAddictsRich

RyanH wrote:
Thu May 24, 2018 5:03 pm
Here's the thread:

https://weightweenies.starbike.com/foru ... p?t=139992

TL;dr is:
  • Changes in temp can affect lap times (laps were roughly 7 min) by up to 10s or so. Environment variables is significant and without using the full Chung Method protocol, recording bariometric pressure, dew point, temp and altitude, trying to compare two efforts even at the same watts is fraught with problems.
  • Precision and consistency of recording devices is essential. I recommend the GSC-10 because I know how it works, one magnet click per revolution. I don't know how the hub ones work as it might be an accelerometer which is not going to be accurate enough.
  • Choose your course wisely. Find a course with minimal wind, little to no traffic interference and no need to brake or coast. Coasting will mess up your data since your PM will still read power for a few seconds. You want to pedal the entire time.
  • Constant wattage isn't necessary. You can actually do more analysis by varing the wattage as it lets you "tease out" Crr.
  • Don't test something once and move on. My goal was a minimum sample size of 5 and to see if that was consistent enough with itself. This right here will tell you if a Stages is good enough or not. When I started, I tried to use GPS and CdA estimates were fluctuating 10% or so for the same equipment and position. My guess is that you'll see something similar with the Stages. Read this for more on why I question anything provided by a Stages: https://www.thieme-connect.de/products/ ... 043-102945 (you seem to be taking training seriously and at this point, you're probably seeking small improvements now, so why use a device where you're not 100% sure that PR you set was due to the Stages or you?). Anyway, Chung method testing is a good way to test power meters too.
  • It may be useful to get a weather reading device like a Kestrel. I got one but only used it for a week or so as I found the nearest weather station read nearly the same. But, I also identified that the other close station was 5-10* higher because it was on top of the valley and the Rose Bowl was at the bottom so there would be big differences in temp even though we're only talking like 75 feet of elevation diff.
I think the course requirements would be the hardest for me ot nail down here... hard to find a solid stretch of road with minimal traffic interference here in NJ. That rt. 29 stretch of road is greta becaus eit runs along the Delaware river and has little to no access on one side. Why did you spend so much time doing extensive aero testing, looking at your USA cycling results page it doesn't look like you've ever even done a TT. Seems like a lot of wasted effort.

Stoo
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by Stoo

Grill wrote:What on earth is wrong with y'all's? I can't believe this has been essentially turned into a fat-shaming thread.
This. Who gives a F.

I’m heavier than 161 at 5’11” and I seem to go ok.
'18 Giant Trinity Pro TT - DA9070 - QuarQ DZero - HED Jet 9+/JET+ Disc3
'18 Giant TCR Advanced Pro 1 - R8000 - QuarQ DZero - SLR1
'16 Genesis Equilibrium - U6800 - FSA SRM - WH6800
'13 Giant Trinity Composite - U6870 - QuarQ DZero

RyanH
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by RyanH

Road aero was a big thing a couple years ago (is it still?) so I wanted to see what aero gains I was missing out on myself. I think the rough summation of my findings was that the Scott Foil (2016 model) was faster but it was like 300w vs 309 for an R5ca at the same speed or about 3%.

I think the biggest takeaway for me was having a better understanding of how the tests in magazines are presented and how they can be misleading. Tour magazine was suggesting a 230w down to a 204w savings but that's misleading because they only test with a half dummy (no upper body) so if you do the math, the actual total wattage should be (I'm guessing because I can't recall) 200w higher for each. So, percentage of the system, it's a much smaller change (12% savings vs 6%).

Regarding the aeropod, that's a friend of a friend's company so I'm trying to get a preproduction unit and I may have another go at doing some aero testing. Just need to find a new location in the middle of Los Angeles.

spdntrxi
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by spdntrxi

Stoo wrote:
Fri May 25, 2018 3:42 pm
Grill wrote:What on earth is wrong with y'all's? I can't believe this has been essentially turned into a fat-shaming thread.
This. Who gives a F.

I’m heavier than 161 at 5’11” and I seem to go ok.
indeed... the average power and speed is good in my eyes so :thumbup:

I wish I was 161 @ 5'8".. I'd hit you all like office linebacker @ 185ish
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quadzilla
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by quadzilla

Great power and speed Rich. solid effort. Whats the (east coast?) racing scene like? Your effort was super strong but on the west coast at my local 10 mile tt the top 5 guys are averaging 360+ watts with many over 6w/kg for 20 mins. some of the fastest official times there have been guys doing over 400 watts. I'm also asking about the racing scene because I might go to college on the east coast and just want to know how it is. not saying one or another is better or easier, just genuinely interested.

mentok
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by mentok

Banging watts on an out and back a few weeks ago. 375W for ~30mins on a 22km course. Surface was rough and kind of slow. My position discipline was pretty good but I could probably have turtled a bit more on a smoother surface.

Really want to replace that base bar with something flat and narrow.

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CrankAddictsRich
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by CrankAddictsRich

Thanks guys... I took a week or so and just unplugged from this thread. My local series had a little 2 week break, that was turned into a 4 week break when one of the races had to be rescheduled. I'm using it to refcus and refine some things. I hit the training hard again (race weeks tend to put a hold on the chance to build, as I'm also trying to focus on not being tired on race day). I've had two big, 300+ mile weeks with alternate long, steady, climby rides and focused pyramid interval trainer sessions. I also made some bike tweaks, changing the gearing from 53-39 crank to 55-42 and moving the cassette from an 11-23 to an 11-25. I also picked up a custom 3D printed TT computer mount for my wahoo bolt. It moved the bolt directly in between my arms, so it won't be stuffed up against my right forearm when the other one had it. I also has a lower stack height since it was made custom for the bolt and even has the full aero shape of the wahoo mount (even though its basically hidden for the wind behind my hands).

Quadzilla... I can't speak for the entire east coast as that's a petty big spread but I can comment on the greater NY/NJ/Philly area... overall, I'd say that that its pretty good. There are very active racing scenes in NY with crits being held in both central park and an old air field called Floyd Bennet field that both have weekly racing series. I don't think there is an active TT racing scene in NY though. In NJ, we have both an active crit scene and TT scene. I'd argue that we have perhaps one of the most well-organized TT scenes in the US. It is a 12 race series that has races all over the state of NJ... long TT's, short TT's, circuit, out and back, point to point TT's and even a 5.5 mile hill climb TT. The series races earn you points to compete for the end of season championship cup. To my knowledge, it is the only series like it in the surrounding states. We have TT riders coming from PA and NY to race in our cup series events. At the end of the season, winners for each class get a trophy cup and champions jersey from Castelli. Cross is also pretty big with a full cup as well. I know that Maryland and Delaware also have a bunch of TT races... I think they're combined into a combination series, but I'm not sure. I went down and raced the Maryland state championship race last year and it was really well run.

As far as power goes, I'd say that the quotes for the top guys in your area are probably a little higher than those here in NJ, but it really depends on who shows up. On any given weekend, if a bunch of the STRONG Cat 1/pro guys show up, then I'm looking at 6th place instead of competing for a podium spot. For example, the race referenced a few pages earlier, the Oldman's TT where I ran 18:19 at 324 watts... Last year, it was won by a guy named Thomas Gibbons at a time of 16:59 and 429 watts, he's a young guy, from NJ, but had been racing over in Europe and he was home to prep for the National championship race.. he won the TT on a borrowed bike. The previous year, it was won by Noah Granigan (SP) who is an up and coming racer on the US scene. He races for Van Dessel right now and is doing crits all over the US. I think he won with a time of 16:57 and 496 watts. There are a handful of other fast guys, Cat 1's, that are all based out of the NY area and race on semi-pro teams, hitting the big races. I'm 39, so I'm sort of past my prime in terms of competiting with the top guys (kids really) that are coming up in the sport. I'm also still very new to the sport in general, though I probably work harder than most to try and overcome that. I know I probably won't ever be the fastest or most powerful guy out there, but if I'm consistent and hit as many races as possible, I might be able to do well in the season lon championship. That's my goal for the season. Are you looking to come to NJ for school?

mrlobber
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by mrlobber

Finally got a decent sideshot in action.
Recent local TT series, 10.6km with a sharp turnaround, 14:48, ~43 kph, pathetic 302 watts.
CdA of 0.22...0.225

Got around 7 secs extra by changing front wheel from Zipp 808 FC tubular to Enve 6.7 with Specialized Turbo Cotton (kicking myself I didn't try it earlier - always lent this wheel for a friend, now we switched, I became faster, he - slower)

Aerocoach still haven't delivered the 100 / disc combo, which I'm waiting since April :roll:
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CrankAddictsRich
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by CrankAddictsRich

mrlobber wrote:
Mon Jun 11, 2018 8:52 am
Got around 7 secs extra by changing front wheel from Zipp 808 FC tubular to Enve 6.7 with Specialized Turbo Cotton (kicking myself I didn't try it earlier - always lent this wheel for a friend, now we switched, I became faster, he - slower)
so what do you think is the cause of the increased speed between the two front wheels? On the surface, I think most peple would assume that the 808 is faster from an aerodynamic standpoint, being the deeper wheel. The atest RR data though says that high performance clincher tires are faster than tubular an the Turbo Cotton is one of the fastest? What tire is on the 808? OR, do you think its smiply that the 6.7 front is still better than the 808, even though it is shallower? Did you guys both run normal power numbers compared to what you might normally run on this course?

Grill
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by Grill

mrlobber wrote:
Mon Jun 11, 2018 8:52 am
Aerocoach still haven't delivered the 100 / disc combo, which I'm waiting since April :roll:
They'll be out shortly. The 70s have started to go out.

mrlobber
Posts: 1928
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by mrlobber

CrankAddictsRich wrote:
Mon Jun 11, 2018 12:48 pm
so what do you think is the cause of the increased speed between the two front wheels? On the surface, I think most peple would assume that the 808 is faster from an aerodynamic standpoint, being the deeper wheel. The atest RR data though says that high performance clincher tires are faster than tubular an the Turbo Cotton is one of the fastest? What tire is on the 808? OR, do you think its smiply that the 6.7 front is still better than the 808, even though it is shallower? Did you guys both run normal power numbers compared to what you might normally run on this course?
I've got Schwalbe Ironman 22mm (one of the first batches, so on paper it should've had latex inside) tub on the Zipp, so nothing catastrophic in terms of rolling resistance, but the facts vs Turbo Cotton look to be there. A month ago, we did the same course with similar setups (except the front wheel swap), I was 15 sec slower, he - 14 sec faster. Watts for me were the same average although month ago my split was way more equal, this time I pushed +11 on the first half of the course and then fell dead -11 after the turnaround :D. For him maybe a couple less, but he pushes around 350 on this course with CdA in the 0.2-0.21 ballpark. The conditions were slightly faster this time.
Minimum bike categories required in the stable:
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mrlobber
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by mrlobber

Grill wrote:
Mon Jun 11, 2018 6:50 pm
They'll be out shortly. The 70s have started to go out.
I've got Masters National championships in 16 days, so they better hurry :)
Minimum bike categories required in the stable:
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by Weenie


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Stoo
Posts: 338
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by Stoo

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I rode this to the UKs 3rd fastest all-time 25 mile TT on Sunday.

44:59 @ 33.34mph average

Only two riders have ever gone faster.
Both have ridden the Giro d’Italia.

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'18 Giant Trinity Pro TT - DA9070 - QuarQ DZero - HED Jet 9+/JET+ Disc3
'18 Giant TCR Advanced Pro 1 - R8000 - QuarQ DZero - SLR1
'16 Genesis Equilibrium - U6800 - FSA SRM - WH6800
'13 Giant Trinity Composite - U6870 - QuarQ DZero

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