preview: Al33 kickstarter launch (new 33mm deep toroidal shaped aluminum rims (465gram) + wheels)

[Multebear]

You're missing the question. Clarify the word significant. Are you suggesting you are faster by several mph? 1mph? Give me a ballpark like one set I go 25mph and with the same effort I go 27mph with the other set. Just curious.

Don't think I do. Significantly faster means, if I'm in a race, it could be the difference between making the break or not. Or getting dropped from a break, or not being able to bridge the gap to the break etc.

[AJS914]

November's calculations based on their wind tunnel data is that you'll be saving a bike length over 25Km @ 25mph. I don't think that is enough of an advantage that you can feel. I have a friend who paid big bucks for Zipp 303s a few years ago. He swore they were significantly faster, like 1-3 mph faster. I'm sure he believed it but it was probably because he parted with so many thousand dollars to buy those wheels.

November's blog also mentions that there could easily be a 20 watt difference between some race wheels with high end tires and one's training tires with lower rolling resistance tires. Their point is that the tires could easily make a larger difference than the rims.

[Multebear]

^and that's exactly my point. Who does the test? Whats their objective? How is the test done?

These tests tend to be a 25 or 40 km tt with the same speed throughout the test with different yaw angles of wind.

That's not really relevant for me and many others. If you are racing, you're not riding the same speed at any time. The kind of races I'm doing are acceleration upon acceleration over and over again. Sometimes you don't catch a wheel when your closing the gap, sometimes you do. And sometimes I'm sprinting away solo until a couple of guys catch me and we work together to keep the chasers away. How does those things apply to the test. Does it change the test result?

What about gusts? Gusts tend to turn the wind when the windspeed increases. How does that affect the test?

And what about number of spokes in the wheels?

All those variables aren't taken into account. It's a lab test, that will give you answers on the questions, that you ask for. But what if you're asking the wrong questions?

And what if you don't like the answers? Who's making sure, that your test results actually find their way to the public?

As Winston Churcill once said: “I only believe in statistics that I doctored myself”

[kulivontot]

Do I take your bullshit opinion at face value without data or do I take the "biased" hard wind tunnel testing data?
You're comparing some unknown rim carbon rim to another rim that you've never even seen. Come back when you've done a thorough factual comparison instead of spouting some nonsense about carbon > alloy. People are here for specifics about this rim; they want real-world reviews and availability info, not strawman arguments against all alloy clinchers.

[ergott]

Sorry, but I've had almost every depth wheelset out there from 32 spoke GP4 classic wheels to Enve 8.9s. There was never an occasion there the wheels were absolutely the difference between hanging on or getting dropped (or dropping others for that matter). The occasions where they make the most difference I can honestly say it's in the few tenths of a mph. If you are blasting along at 35-40mph they yes it might be closer to the 1mph mark, but certainly not more. I'd say it's more likely half a mph at best and no one is doing prolonged efforts at those speeds. (net speed, not counting tail winds or drafting).

Yes I've raced all these depths as well. In the last 15 years I've probably owned about 10 very different sets of carbon wheels (Edge Composites 24 and 38mm, Zipp 303 and 404, Enve 66, 4.5, 6.7 8.9, Rail 52, Reynolds 46, 66 and some others) . I usually ride a new set each season.

They are a blast to ride and I'm usually out on a set of Boyd 44 tubulars when I'm feeling a bit spirited. That sure doesn't mean that if I bring out my other bike with 20/24 aluminium wheels I'm worried about keeping up.

[antonioiglesius]

I think Multebear is saying that in real life there can be many more variables that aren't accounted for in the wind-tunnels. That seems plausible. The issue I think is that there isn't a way to get at aero data in the real world (IIRC there's a company, I want to say Argon? That came up with a mounted sensor that captures some, not all, wind-related info). Without hard data, it really is difficult to convince some people (e.g. me) that certain profiles/rims work better than others... What needs to happen is a) sensor(s) that accurately collect real-world wind data and b) democratization of sensor reading gathering and analysis (i.e. from users, not manufacturers nor dealers). Without these, it's just effectively individual opinions...

[Multebear]

^that's exactly what I'm saying. Very well written. Thanks.

And I agree, I haven't seen the A-force rims. And maybe that's part of the problem. Very few have. It sounds like they are the holy grail of rims - carbon killers. If they were, why can't we get our hands on them?

[ergott]

You guys make it sound like wind is this mythical force that can't be studied just because you can't see it. Not only cycling, but the airline and automotive industries know otherwise. Even if you take marketing babble with complete suspicion you can easily look at the general trends. There have been enough independent studies done and they all back up similar conclusions. There are differences, but they are considered rather small with respect to the larger forces a rider must overcome at high speeds.

[mpulsiv]

November's calculations based on their wind tunnel data is that you'll be saving a bike length over 25Km @ 25mph. I don't think that is enough of an advantage that you can feel. I have a friend who paid big bucks for Zipp 303s a few years ago. He swore they were significantly faster, like 1-3 mph faster. I'm sure he believed it but it was probably because he parted with so many thousand dollars to buy those wheels.

November's blog also mentions that there could easily be a 20 watt difference between some race wheels with high end tires and one's training tires with lower rolling resistance tires. Their point is that the tires could easily make a larger difference than the rims.

Indeed, anyone will swear that new wheels are significantly faster. In this case, it's your friends who dropped some coin on Zipp 303. What is he going to say? "I just dropped $2000 on these and can't tell the difference?!
I'm reposting this for those of you that haven't seen this.
_______________________________________________________________________________________________________________________________________________________________
There's a delta of ~ 3 watts of drag at 10 degrees of yaw angle between Zipp 303 and Al33. "10g of drag roughly equals 1 watt, and 1 watt roughly equals 3 seconds in the mythical 40k. Not good enough for real science, but good enough to become a hyper-aware wheel consumer." Do you really need $2000 Zipp 303 wheels when Al33 would do? We are talking about ~0.3 watts (at 10 degrees of yaw angle) and ~0.1 watt (at 10 degrees of yaw angle). In 40k, this roughly translates to ~1.5 seconds. Am I missing something here?

Source http://www.novemberbicycles.com/blog/20 ... lloys.html
FLO claims that 80 percent of the time cyclists experience between zero and 10 degrees of yaw. Source http://flocycling.blogspot.com/2016/03/ ... tep-2.html

[Krackor]

_______________________________________________________________________________________________________________________________________________________________
There's a delta of ~ 3 watts of drag at 10 degrees of yaw angle between Zipp 303 and Al33. "10g of drag roughly equals 1 watt, and 1 watt roughly equals 3 seconds in the mythical 40k. Not good enough for real science, but good enough to become a hyper-aware wheel consumer." Do you really need $2000 Zipp 303 wheels when Al33 would do? [color=#FF0000]We are talking about ~0.3 watts (at 10 degrees of yaw angle) and ~0.1 watt (at 10 degrees of yaw angle). In 40k, this roughly translates to ~1.5 seconds. Am I missing something here?

Check your units again. Delta of 3 Watts of drag equates to 9 seconds over 40k. Looks like you mis-applied the grams-to-watts conversion factor.

[mpulsiv]

_______________________________________________________________________________________________________________________________________________________________
There's a delta of ~ 3 watts of drag at 10 degrees of yaw angle between Zipp 303 and Al33. "10g of drag roughly equals 1 watt, and 1 watt roughly equals 3 seconds in the mythical 40k. Not good enough for real science, but good enough to become a hyper-aware wheel consumer." Do you really need $2000 Zipp 303 wheels when Al33 would do? [color=#FF0000]We are talking about ~0.3 watts (at 10 degrees of yaw angle) and ~0.1 watt (at 10 degrees of yaw angle). In 40k, this roughly translates to ~1.5 seconds. Am I missing something here?

Check your units again. Delta of 3 Watts of drag equates to 9 seconds over 40k. Looks like you mis-applied the grams-to-watts conversion factor.

Ah my bad, so there's a 9 seconds delta at 10 degrees yaw. Between 0-9 degrees yaw, the delta diminishes. In summary, $2000 Zipp 303 could save you ~5 seconds on average (from 0-10 degrees yaw) in 40k, right? This is with almost 15mm of depth (from 33mm -> 45mm deep rim). The reason I say almost 15mm is to analyze the wind tunnel provided FLO. They were able to yield 17 seconds advantage in 40k, from FLO 30 to FLO 45 wheels. To conclude this, modern 30mm aluminum wheels perform exceptionally well. Now that this aero data is widely available, it's time to focus on aesthetics, thus black brake track. This could hurt sales of carbon wheels.

[morganb]

I ended up getting rims only through my local shop to build to Bitex hubs so I didn't get any pads. I guess that I will try out the Kool Stop ceramics unless the Shimano ceramic compound is much better. I wanted to ride the wheels so I did a short ride on Kool Stop salmon pads and used up half of the pads in an hour and a half. The texture completely chewed through normal pads. I will say that the ride quality is fantastic, I did 24/28 spokes CX Ray/Sprint DS and they are stiff yet comfortable.

Does anyone have a brake pad recommendation to use with these? I got the ceramic coated ones and a not sure if my normal pads (Kool Stop Salmons) will burn through quickly and/or wear the coating faster.

well, the description says "ceramic specific pads"...which will be included in sets of wheels.
not sure which other compounds will work,
however koolstop has some options...: Kool Stop R4 Dura Keramik

best to ask Jan directly ...
quote from kickstarter:
..."Wear of the brake pads depend on the kind of pads used.The pads supplied do wear quite quick if compared to standard alloy pads, As we designed these purely for optimal braking power.
For example they also work fine with our carbon pads and the pads last a lot longer, Also good modulation but just a little less power. (still comparable to standard aluminum rims if not better).
The first pads will go faster, After 1 set of pads wear speed will be reduced as the rims will wear in."

[glepore]

I have about 200mi on a set of these now. Corsa 25's mount easily but balloon out to a little over 28mm, pretty close clearances in a supersix evo. They ride like, well, wheels. Good wheels. Coming off of open mold 50/25mm, they feel about the same, a little lighter but no slower. Yes, subjective.

Weight w/ bitex hubs in 20/24 was 1575 including rim tape. Maybe 40g heavier than I expected.

Braking feels like a typical alloy rim. The pads that November supplies were a serious beyoch to get into ee padholders, even with a little lube on the back. They seem pretty abrasive, and grip the padholder too well, don't look forward to swapping them out. Dave, have you tried Campy Red's with these?

[Multebear]

Coming off of open mold 50/25mm, they feel about the same, a little lighter but no slower. Yes, subjective.

Are you talking about carbon clinchers? Which ones are lighter? Open mold ones or A-Force?

[glepore]

Yes carbon clinchers. The aforce are around 100 g lighter but I don't subjectively feel any less aero speed. It was gusty over the weekend and the aforce were quite a bit less blown around than the guys on 404s


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