Talking about discs:
Does anyone know of independent data about the fastest disc wheels?
The Roval 321 seems to be among the fastest, as many pro teams use it, unbranded.
Revolver and Aerocoach claim their Discs are mildly faster.
But no tests, that were independently taken….
Or are all discs weighing 1 or 2 watts?
My impression the last few years is that there is little discernible, meaningful differences between discs…mostly because they aren’t used in static conditions. Some may perform better or worse (in terms of wattage) depending on the conditions of the day.
But all are within a few watts of each other…so my default would be to pick the one with the best “whomp whomp whomp” sound. 
3 Likes
I think at the moment it’s about availability of the disc disc as not all sponsors have one available and as we all know equipment isn’t growing on trees at the moment. Look at Alpecin Fenix having to get someone to drive a pair of wheels they borrowed 1000km over night at the tour.
That aside - I think independent testing of discs is going to be meh - frame and rider are going to be an influence on it. I do think though that this is where you want to look at frame/wheel packages, I’d put money on the 321 being the fastest disc in a shiv, like wise a bontranger disc in a trek.
Otherwise I think there is not much in them IRL.
Interesting however, how Jumbo and Fenix appear to use 321 discs, when they use front wheels from other non-sponsor makers.
Jumbo uses AC front, 321 rear -
Van der Poel used Aerocoach front, 321 rear, and Princeton front 321 rear.
Ganna used both AC front and Princeton front, and Princeton rear.
The Bontrager disc was just a rebranded Zipp Super 9 wasn’t it?
I would put Alpecin and Jumbo into two different categories of teams.
JV and Ineos are teams that are willing to invest in TT, likewise surprisingly, EF . These are teams that have TT equipment by the warehouse a willingness break from sponsor equipment for key TTs and staff to model courses, make equipment choices, invest in fitting riders even during lockdown, etc, etc. These teams win TTs.
I think Alpecin are in the category of teams that do well by playing along, either a rider or someone in the team is interested in this stuff and doing it. Like ISN have Dowsett, (FDJ when they think it will matter, Grapé & Pinot have some good papers published around aero testing and positioning). Surprisingly Arkea here also. In the case of Van der Poel at the tour, I think it was Canyon putting the pressure on to make sure that bike was as fast as possible. I don’t know what equipment the rest of Alpecin were on in that TT - I guess that’s the stuff the team has normally. .
Then there are the other teams - ride the bike the day before the race and perform as expected.
I think the big looser in the disc disc world is shimano - mainly no Pro disc disc has enabled a lot of other competent manufacturers to get good advertising. We need a better way of describing disc discs than disc disc.
No idea - if so probably the wheel to go for. Speaking of Zipp did they used to do a disc that you could swap the axle and convert to a track wheel - is that still a thing?
Yup, that’s the Super 9. I have both a road hub and a track hub for mine, though my primary TT disc is the Roval 321.
1 Like
There is no current Bontrager disc, and with the 75 being released long before the the new Speed concept, I just don’t think there is one around the corner.
AF is not the most geeked out team, but apparently they went the extra mile for the great Matt.
1 Like
Curious to know many watts are you saving going from an 80 to a disc in the rear at 45 kph? I’m trying to justify the decision to upgrade from a rear ENVE 7.8 to a full disc… 
Whomp Whomp Whomp
All the justification you need.
4 Likes
What about front wheels (RB)? I currently have a farsport 80mm but since I’m waiting for Aerocoach to finish my Ascalon Bars,
I’m tempted to pick up the Titan front wheel and have them shipped together.
I ran the rim brake Titan for a while and it’s very fast. I unfortunately didn’t get to do any testing or races on it before that bike was totaled. Being 100mm, you can imagine it’s pretty unruly in wind, but it wasn’t as unstable as I would have expected. I felt that it was more stable than an Enve 8.9 (85mm) or Zipp 808 front.
1 Like
Wow that stinks… but good to hear that it’s actually fast. I definitely need to consider it as an option.
Another marginal gains question I have:
What are the width of current gen TT Bike base Bars?
My Large Shiv TT has a 40mm c2c base bar, the new Speedmax is listed as 39mm.
For me, the narrower, the better. I don’t need those, at least not for what I am planning on, for climbing or sprinting. So narrower should yield a lower CdA and also more inline with the legs, which might be relevant.
I am especially asking if anyone knows if there is 38cm option for Cervelo P5 (2020+)?
I can’t get that excited about narrower bars on a TT bike as you are on the base bars for such a small proportion of the time (and much of that would be braking anyway).
Now, on a road bike, yeah definitely, as you are on the hoods or drops most of the time, and it alters your body position as well as just the bike itself.
1 Like
Exactly, get rid of them, they’re a weird useless appendage sitting in the wind causing drag.
I think minimum is 30cm, I’d run those in a heart beat.
2 Likes
I have 38cm base bar on my TT, I run 38cm drop bars anyway, so matches what im used to
2 Likes
What base bar are you running?
Bikes with non integrated cockpits are not a problem, really, as you can just swap those out. Not so much for the integrated ones.
Pinarello Bolide apparently is very narrow. 38 or even 36 would be ideal.
1 Like
just some generic carbon ones, its not an integrated cockpit