6-12-24 World TT Championships, Report from Borrego Springs: brief
- Thread starter Jim Parker
- Start date
RojoRacing
Donut Powered Wise-guy
:lol I feel like this just happened a few months ago 
RojoRacing
Donut Powered Wise-guy
Maybe I should start coaching like Marko. Guy is getting $275 a month per person to email out a monthly training plan and some emails, and that's the cheap option
Who here want's to send me $100 a month and I'll email you a training plan and a box of donuts?
Who here want's to send me $100 a month and I'll email you a training plan and a box of donuts?
RojoRacing
Donut Powered Wise-guy
scale is in storage somewhere so fat chance of that happening any time soon. Last I remember it was 26-27lbs that would be with pedals of some type and no idea if that included tool bag or other accessories. Only way I remember the weight of my Ridley was I wrote the weight under the seat but then I change the seat last year and now I can't remember.
Power vs. speed comparison for the fastest 18 mile (long lap) at Borrego Springs. I was 80 seconds faster then Jason, but he was burning 15 watts less.
82 seconds ahead of Kevin, but burning 2 fewer watts. I would conclude I was certainly more aero than Kevin, and maybe a bit more aero than Jason.
Strasser's fastest lap was 42:57 (ranked 4), but his power numbers were not on Strava.
Jim
82 seconds ahead of Kevin, but burning 2 fewer watts. I would conclude I was certainly more aero than Kevin, and maybe a bit more aero than Jason.
Strasser's fastest lap was 42:57 (ranked 4), but his power numbers were not on Strava.
Jim
...and here are the Cd*A estimates (and the input parameters) using R. Chung's cool online tool.
The Ninja V18 adapters and/or the Quiver tailbox must have helped me out.
Surprised my rig slipped through the air a little better than Jason's custom carbon covered frame.
This table is based on Strava speed and power for the fastest 18 mile lap, and my estimates of the rider/bike weights.
Kevin's wheels got damaged in transport, so he rented a set. Maybe they account for his higher Cd*A.
The Ninja V18 adapters and/or the Quiver tailbox must have helped me out.
Surprised my rig slipped through the air a little better than Jason's custom carbon covered frame.
This table is based on Strava speed and power for the fastest 18 mile lap, and my estimates of the rider/bike weights.
Kevin's wheels got damaged in transport, so he rented a set. Maybe they account for his higher Cd*A.
ratz
Wielder of the Rubber Mallet
Now drop in a watts / kg column and we start to get some interesting stuff. I didn't realize Baloh was that light; he looks bigger than 175 at that height.
LarryOz
Cruzeum Curator & Sigma Wrangler
Quite impressive Jim....and here are the Cd*A estimates (and the input parameters) using R. Chung's cool online tool.
The Ninja V18 adapters and/or the Quiver tailbox must have helped me out.
Surprised my rig slipped through the air a little better than Jason's custom carbon covered frame.
This table is based on Strava speed and power for the fastest 18 mile lap, and my estimates of the rider/bike weights.
Kevin's wheels got damaged in transport, so he rented a set. Maybe they account for his higher Cd*A.
This is so very close to my results and speeds with my testing at my local track earlier this year:
I took the speed and wattage data from several different runs and ran them through Chung's model, after processing the .fit file into the CVS file needed for Chung method, this is what I came up with:
V20 @ 150 watts = CdA= 0.154, avg speed = 38.66 kph = 24.02
V20 @ 203 watts = CdA= 0.160, avg speed = 42.8 kph = 26.6 mph
V20 @ 288 watts = CdA= 0.163, avg speed = 48.5 kph = 30.14
Speeds are probably faster because of the constant track elevation and me and the bike weighing in at about 170 lbs.
Hi Larry,
Yes, the 18 mile loop had some climbing/descending and most of it was pretty rough. Those factors are going to make the calculated Cd*A a bit higher than on a smooth track.
super slim
Zen MBB Master
I think your tail-box has a BIG aero benefit!
Larry have you done any tests with & without you tailbox?
How many inches did the Ninja V18 drop the height of the top of your shoulders from the ground?
What is the height of the top of the shoulders above the ground of Jason and Kevin?
The V18 adapters drop my head and shoulders about 3 3/4 inches (9.5 cm). Some time when I have a low-wind day and time off work, I will do proper Cd*A testing on a 9-mile loop near my house to better quantify what the tailbox does, and what the V18 adapters do.
super slim
Zen MBB Master
What is the front/rear wheel loading with/without the V8 adaptors?
How much does it extend the wheelbase?
How much would this reduce the rear wheel loading if camping rear pannier weight of 18 kg (40 lbs) was added to a Silvio?
Last edited:
LarryOz
Cruzeum Curator & Sigma Wrangler
No, I have not done any test with my little tailbox.
It is pretty hard to take off and put on, so have not pursued it.
I will see if I can get an extra headrest from Cruzbike and then I can do some decent testing.
I will say upfront, as I don't expect much if any different comparable to putting a visor on the Giro helmet.
My little tailbox (really a dual wattr bottle and tool holder) is already in my slipstream and it is not designed to join the airflow back together. (If it was, it was be dis-allowed for non-faired bike.)
I think where a good test would be is to compare this water-bottle-holder-tailbox with the other "water bottle" holder where the bottles are behind your head and sholders on either side, and with sticking the water bottles under the seat.
This is where I think you would see a bigger difference, especially having them under the seat.
DavidCH
In thought; expanding the paradigm of traversity
Ditto
PeteClark
Active Member
Why not just run a smaller diameter rear wheel?
RojoRacing
Donut Powered Wise-guy
Because the whole reason for running 700c wheels is to take advantage of the superior rolling resistance of larger diameter wheels.
John Dorlon
Guru
super slim
Zen MBB Master
what are the heights of the different riders, to get an idea if it effects the CdA readings?
