funny my golds on 3 bike all squeal horribly so that i will switch them out.

Curious to hear what your rotor and wheel setup is, and what other pads you’ve tried

While I generally think steep seat tubes and long frame reaches are here to stay, I do think stack height is an area where all bikes should be low. In principle it could make perfect sense: just accommodate different stack philosophies at the level of the handlebar/stem. It's lighter and more aero as well.

Incolor just shared this teaser on Instagram...renderings of what appears to be various iterations of TT bikes that are a copypasta of the Hope, Look, and Pinarello track bikes, as well as the seat tube from the V1RS (?) for good measure. And the "I am speed" catchphrase too, lol. Ka-chow!

Shanghai bike show should be exciting, no?

I've never seen testing done on those wheels, only CFD, and it was rim only. University students also did it as a sponsored class project, which is not good or bad, just context for why it was limited in scope.

Agree that the time for wavy rims as a "good" solution has passed.

I also agree with the framing of the trade-offs if we consider the shape of a rim in isolation. Rims exist as part of a wheel with tires on a bike, though. In that light, there is not a clear trade between stability and CDA.

For example, you can gain stability and lower CDA by tuning your rear wheel profile to be optimized for the lower yaws it will see. This is the same principle behind the observation that many TT and tri riders have that a rear disc wheel makes the system feel more stable when flow detaches from the front but stays attached in the rear. Following this principle has made the Enve SES wheels among the best for over a decade now (and the 4.5 design is nearly 10 years old now too!). This is the same concept Roval has also been using in their last few generations of wheels. Despite their latest rim profile being shallower in the rear, if you look carefully, they are still following this principle.

Another product that breaks this is the Aero 111 tire. Nearly every test finds that it makes less wind stable wheels more stable while also testing consistently faster in the tunnel, granted, faster in these cases is within the error of the individual tests. I think the reason this works has a lot to do with the top of the tire moving faster relative to the front as the wheel both rotates and moves translationally through the air. With some bikes, this effectively helps with poor aero areas around the fork crown, so it's doing more than you would see in a wheel-only analysis.

My armchair guidance if someone were to want to buy a steel spoked wheelset would be to get the DFS wheels on straight rims with the R2 hubs (since you cant get wavy rims for those hubs anyway). I would pick either their wide shoulder 50mm deep profile for the front or their 50mm deep CX profile (and match with the Aero 111 like I did), and then go for a UV shaped rear. You can see the writeup on my choices here: https://chinertown.com/index.php/topic,6243.15.html I don't think it's outdated yet, and I believe the rim profiles I used are pretty similar to what CRW ended up using on their second-gen 5060

I agree 100%. I think a better phrasing of the trade-off would have been that "side-force vs low cda is something of a zero-sum game". Side-force is really a red-herring in the stability discussion, which I think is illustrated by the fact that Conti 111 tires make wheels feel more stable, despite all the data I've sheen showing they enhance airflow attachment, which means they will generate more peak side-force.

The actual threat to stability is a combination of high side-forces and how deterministic/chaotic airflow attachment/detachment is at the limit. I realized this many years ago riding a set of 404 firecrest tubulars in a crit, and feeling that at a very specific point in a corner transitioning from cross-wind to head-wind my front wheel would repeatedly get sucked into the headwind and then jerk away at seemingly random times. I later realized this was because at that point in the corner, the rim angle relative to the wind was at a critical point for airflow attachment, and that the state of airflow attachment was determined by chaotic dynamics.

This is why I said

I think a better ideal is you find a rim profile that stalls more slowly and predictably

--the wheel will feel stable despite a lot of side force as long as whether the airflow attachment is predictable, and especially if the stall characteristic is gradual, not sudden. If you really think about the word stable, it refers to not only the magnitude of change, but also its frequency and predicability.

My understanding is the Conti 111 improves the predicability and suddenness of the stall characteristic is because those little scoops are vortex generators that energize airflow (and help it stay attached longer over wider yaw angles), but with regards to stability these vortices are a more deterministic dynamical regime that stalls more predictably than in the absence of vortex generators.

In the end I really agree with your "armchair" guidance. A deeper rear wheel is also stiffer, which means you can run fewer spokes and have an equally strong wheel (I'm running a 21 spoke setup on my handbuilt deerobust wheels)

I honestly think the wavy rims are a net aero loss. The Princeton 6050 Evolution wheels didn't do particularly well in the 2024 CyclingNews aero wheel test (link: https://www.datawrapper.de/_/n786I/) especially at high wind angles.

My explanation for this is that while the undulations are meant to shed airflow to promote stability, they are bad for drag since airflow shedding/detachment means more of the surface is generating more turbulence across a wider range of wind angles. In other words, wavy rims are designed to deliberately stall the aerofoil unless wind is head-on to reduce side force in cross winds, but this comes at the expense of drag--or at the very least doesn't reduce drag in any way.  Marketing materials for wavy rims seem to implicitly admit this. For example, Zipp's blurb on the NSW wheels states: "[the rim shape] simultaneously reduces both aerodynamic drag and side force"--they're really careful to not directly state that the sawtooth profile reduces drag at high wind angles, only claiming that it reduces drag and side force.

My read on this is that stability vs low cda is something of a zero-sum game. Just as an airplane wing generates lift (a lifting force on a horizontally oriented aerofoil) your rim is a vertically oriented aerofoil that efficiently generates side-force when it hits wind at an angle; the better your wheels are at keeping airflow attached, the more side-force they generate before the aerofoil stalls, and when they do, that side-force you were counteracting to keep your handlebars straight suddenly disappears. Conversely wavy rims stall the aerofoil at wind angles where you aren't counteracting so much side force, so the wheel feels stable, but theoretically this costs drag.

I believe wavy rims are a bad solution to the stability problem. The design introduces a lot of parameters to be optimized (and to screw up)--not only aerodynamically but also from structural and production engineering standpoints. I also agree they look pretty kooky and gimmicky.

I think a better ideal is you find a rim profile that stalls more slowly and predictably (against the natural tendencies of air), and the marketing on pretty much every non-wavy rim these days says something suggesting that their wide/bulbous/toroidal/blunt/whatever shaped rim profile enhances stability in this manner. Under the assumption that I can't see aero and correctly identify what such a rim looks like, I think everyone is just better served running slightly shallower and wider rims if you want more stability.

The answer to your last two questions:

2) not interchangeable, nearly all companies use a custom/proprietary port screw

3) the seal material is different for DOT and mineral oil, so yes, it will matter

After suffering my own adventures bleeding these calipers, I want to reiterate precision6625's advice. You need to directly bleed the caliper, especially on the rear wheel where the caliper's orientation will trap air at the top.

To do this you need a good bleeding syringe and an adapter that fits the ZRACE caliper bleed port. I'm guessing it's an M2 thread? Bleed port adapters that fit are hard to find. I use the funnel adapter with the smallest thread available in EZ MTB's 10 piece plastic adapter fitting kits. I jam the open tube end into the opening where the funnel normally goes. The diameters match up perfectly and create a seal. I believe if you have the brass kit you can put the funnel on and jam the tube into the funnel opening.

From there you pull on the syringe to pull out air and push mineral oil back in--if you're familiar with SRAM's bleeding procedure it will be similar.

Like precision6625 said, Hope's instructions are a good description of the steps if you are unsure.

I have Cybrei, Lexon, and Rockbros. I would suggest going with Cybrei if you can afford it - overall, the quality of each part seems higher.

I find it unsurprising a product that costs twice as much is higher quality than the cheaper one.