Yes, I was looking at this nearly swirly zone over your left hip. It doesn’t look like there is a similar zone on your right side (or maybe its just hard to see from this angle). I was wondering why that was there - is it because the airflow is faster on your right side (as you’re cornering on the track - that would make it a high pressure zone on your left?). Or maybe it is simply because your left leg is lower, and the little red threads get shaken about by the pedalling action?
(I’m rubbish with aerodynamics, so no idea if that is something that can be used to get faster or not! Just found it interesting)
Its most likely because the airflow behind the rider forms into two vortices, one behind each hip, that oscillate as each leg drives up and down (and probably in response to the other vortex). So, as one leg is at the bottom (in the photo) the drag is greatest, the vortex is biggest, and its pulling air into the low pressure behind the hip (which is indicated by the traces on the lower back). I’d expect those traces on the lower back to wag side to side as the rider pedals, and the vortex wags side to side. I think this is probably the reason for the bottles on the sub-7 ironman bikes - they control airflow off the back.
There are some interesting computer simulations online, I think Swisside posted one on youtube.
Thanks, yep, that helps! I was also thinking about those gravel test results where a bottle in the jersey pocket tested faster. Maybe having something in the middle between the two vortex helps keeping them more stable?
Hi guys. Again a question about di2 shifting setup. The brake/shifters i have bought have one button on each side. So i think i need this shifters for the bars:
The setup will be left bar: frontderailleur up and down. right bar: back derailleur up and down.
Brakes left back derailleur down, right back derailleur up.
Will this setup work?
When i put this shifters on the aerobar and i place the buttons on the side, i will not have problem with accidental pressing i think.
My understanding from the Bettershifting site, is that with the older two button ones, you can configure to shift up and down as you like (as I have them configured) the left pair of buttons controlling the front mech, the right pair controlling the rear mech.
However the single button ones, when used 2x, can only operate in synchronised mode, that is they choose to change the big ring, depending on where you are on the cassette. Though I believe it is programmable using the shimano software.
I have the two button (older) Di2 with bar end and brake lever shifters. The problem I had installing them with bars ends close together is that the buttons are designed to be on the inside - so if the bars ends have an entry point for the Di2 cable underneath (as aerocoach and D2Z bars do) , the switches are very close together and hard to get thumbs in as well to get to the buttons. I ended up taking a small drill to the Di2 shifters to carve out a short slot that enabled me to change the exit point of the Di2 cable position to further around the switch. I can now position the shifter and buttons at an angle more facing me, allowing the cable to exit at 60+ degrees from where it normally exited… and a much better position for my thumbs and hands close together. I still occasionally accidentally shift the big one, but its not an issue.
Shimamo did not introduce new Di2 shifters for 12 speed, so there is a software upgrade to the Di2 (as well as having to but the new front & real mech and batteries), that makes upgrades from 11 to 12 speed relatively simple. This is a useful read on both synchronised shifting, choice of set-up and 11-12 speed conversion.
However the single button ones, when used 2x, can only operate in synchronised mode, that is they choose to change the big ring, depending on where you are on the cassette. Though I believe it is programmable using the shimano software.
You can set up the buttons to do whatever you like using the software from Shimano. I used to run 2x and at some point the full-syncro shifting modes refused to work (after a software update on my front mech) and I set it up that the base-bar shifts the front and the extension shifters shifted the rear as a quick fix
North East 25 mile Champs this weekend. Dual Carriageway course and as ideal weather that you can get in the NE.
51:39 off 336w (~4.5w/kg). Looking at pics am thinking the next port of call are some extensions that can close the gap between them and the forearms. Suggestions always welcome (not quite willing to drop 1k+ on the super-extensions)
Iam looking for a program thats make from a GPX file a google streetview ride wich i can play in a chosen speed. That will help me to visualisate the race course in the weeks before. Visualization is important to perform better
The D2Z extensions are a good cost effective option. The problem with the trek mono adapter is that the clamping point is quite far forward, so unless you’re crazy long at the front, you’ll probably need to use the lower rise poles, and that’s going to limit your position.
I’m using the D2Z adapter plate now, which gives a lot more adjustability, but by the time you’ve bought all the bits it’s close to £500 .
My slow start to the season continues, only managed two opens so far (4th and 2nd), had two races cancelled. A few midweek TTs with Cambridge CC, including on my favourite E33/10 last week, where it was so overcast we we’re basically racing in the dark. Good job front and rear lights are now mandatory!
As I - again - didnt use my Troika TMD due to crosswinds on Sundays TT in Weiden - Germany (it just feels so unstable, especially when the wind is gusty // you ride out of cover from the wind) I am looking to something thats ideally as stable as my Enve 5.6 (the older ~2019 model) front wheel, but maybe a little faster.
What Roval did you test there? I guess the Roval Rapide CLX? Or would an Enve 7.8 maybe be even better for me, as I already got a 50mm front wheel
I’d definitely recommend a Rapide CLX II.
It being a hooked rim definitely makes sense for TTing, with narrow tires at high pressures. Also, you can use non-HL compatible tires like Corsa speed and Veloflex record.
Lastly, the CLX is probably like 1-2 watts slower than a 7.8 or something similar. However, you can ride it in absolutely any conditions. Keeping your head down a few more seconds than with a deeper wheel will likely undo all the aero losses
So as stable as my 5.6 but maybe marginally faster. Sounds good enough - this way I could also run normal GP5000 on the 5.6 front again and not worry about puncturing due to riding on TT tyres even in roadraces.
Have you tested the mistral yet? When I compared with the tempor, I only saw a difference of .001 even with a noticeable gap to my back with the mistral. The test was at 0 yaw so not sure what would happen with a crosswind.
I tested both when I was in the tunnel. For me, both were similar at 0 yaw but the tempor was fastest at yaw. The difference wasn’t much and in the real world I’ve never gotten great results with the tempor. I assume I move around too much?
Just migrates downwards from the road vibration
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