http://forum.slowtwitch.com/...vs_the_404_P3513507/

I don't see 303s on there.


Am I blind?

You're kidding right? I read that thread before I posted. Although it started on topic, it came to no definitive conclusion, and then quickly descended into an argument about whether Vaughters did the right bike selection for the team on the mountain TT in the TDF.

The first graph has a line labelled "9993: x45 FC, GP4000S-A-23mm". I've interpretted that to be the new Firecrest 303.

No. I think the first page (and first several posts) answers the question. The second page is for entertainment.

I don't think so. That thread was before all info was out, and the last person that commented said:

"I'd take a 100 gram weights savings over saving 1 watt every day. Figure in a pack that 1 aero watt would be effectively non-existent. "

Which is exactly where I started this question. Why would you chose the 404 over the 303 at this point?

As for entertainment value, I think the "Di2 -- one year on " thread wins that prize!!

Because as little as 1 watt difference is (and it would be more than that anyway), even after you whittle away at it by 30% in a pack.

it still speeds you up better than 100 grams does =)

for instance say you are climbing a 2000 meter 4% climb at 250 watts, and you drop 100 grams off your wheels. you will save 0.25 seconds

1 watt will save you .96 seconds

.75 watts still around .7 seconds


redo this math where its flat instead of 4% up and aero wins even more of course

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

I've combined those two charts into one, along with the 808 data here:

https://docs.google.com/...wMXVQeXFoWnJxS2doYUE

what I conclude from it is that the 303 data you found was done probably with different tires, different protocol, and the graph is wacky as they skipped a couple yaw angles. So I wouldn't trust this as a comparison at *all*. It is very unlikely that the 0 deg yaw difference is really that big. same for the 20 deg yaw.


also get the 808

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

Link does'nt work for me. But based on what you said, it sure would be nice if Zipp would just produce a nice 'apples to apples" aero compare set of charts for representative tire widths so that we could see the differences.

I agree, but still

808/disc for tris/tts

404/808 for bike racing

303 tubies for hill climbs

thats pretty much going to be the way to go 99.853% of the time

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

What are you using to calculate the red?

What difference between 100grams on a frame and 100grams on a wheelset?

Is there a difference between two wheelsets, one with a 800 gram hub and 200 gram rim and the other with a 700 gram hub and 300 gram rim? (same spokes)

http://www.analyticcycling.com/ForcesSpeed_Page.html

the difference between wheel weight and frame weight is very very close to zero. even when accelerating all out in a crit.

similarly, it doesn't make sense to worry about whether a wheel has less rim weight/more hub weight.

we all know from high school physics about inertia, but the values are just too small to matter with human cycling acceleration rates.

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

"What are you using to calculate the red?

What difference between 100grams on a frame and 100grams on a wheelset?

Is there a difference between two wheelsets, one with a 800 gram hub and 200 gram rim and the other with a 700 gram hub and 300 gram rim? (same spokes)"

As Jack said analytic cycling is an excellent tool. As far as how the weight is distributed between hubs and rims, thats not a very big deal at all. Less weight is pretty much less weight, if you can remove a 100 grams from a rim, do it, if you can get a lighter hub do that. Ideally do both.

As far as your 303FC vs 404FC, I'd ask Zipp if they have a comparison. They tend to be pretty open. If the difference do tend to be what you have gotten so far keep in mind that the steeper the hill the more weight is magnified and the less aero matters. So at 4% the analtysis shows a wash but a 8% or 12% hill is going to show a much greater delta. Also analytic cycling also assumes you ride at a steady state. Newtons law is F=Ma assuming a ride has a steady a is going to give very small deltas for F. I pride myself on being an excellent pacer, but I don't think I've ever ridden very far without changing speeds. Its still not not going to make 100 grams turn a Cat4 rider into a Pro, but it will make it bigger.

The other thing I don't think most people take into effect is real world riding conditions. I do a lot of group riding in hilly areas with riders who are better than I am. I can hold my own on the flats and rolling hills. Drafting skills, taking shorter pulls, trying to be at the front when a hill starts and then drifting to the back as you climb can all help. In any ride or race when the pace is high and you hit a steep or long climb is where you start to see people shelled off the back. that holds true for local group rides and it holds true for the TdF. If two wheels are almost equal but one has a slight benefit one has a slight benefit on a climb, I'd chose the benefit on the climb. Even if I'm 15 meters behind the front group on a climb its hell to catch back on. Then you are solo riding vs a group of strong guys.

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Styrrell

Thanks. I'm actually usually the one pulling in our group, so I went with the 404fc's. Took the great deal at bicycleoutfittersindy.com.

Bastard. Just kidding, but it had to be said for the guys that are trying to hold on that now have to try that much harder.

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Styrrell

Damn straight!

Ps. Fully expected Tom A. to chime in on this thread, but guess you wore him out on the other one.

My only take on this is that if one insists on running 23C or greater tires, then they're probably better off on the FC303s.

If 21C or 22C tires are OK with the rider, then the FC404 is most likely the best all-around choice.

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http://bikeblather.blogspot.com/

That's because you are trading off the aero for weight. It's easier to catch back on after a climb with more aero equipment ;-)

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http://bikeblather.blogspot.com/

Interesting..........22c vs 23c would make it different. I thought the aero advantage of the 404's at the usual yaws was large enough on either size. I will repeat that I wish Zipp would publish good "apples to apples" numbers with various tire widths so that informed choices can be made.

Typically not. Most of the time after a climb the fastest guys are the best descenders, regardless of equipment,

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Styrrell

i looked at that but it looks like they're the regular 404s and not the firecrest 404.

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Fruit snacks are for winners

They stock the firecrest ones too, and the christmas11 25% off code applies

Sure...but also typically the better climbers aren't necessarily the best descenders either. It also depends on the course.

Here's what I know (yeah, n=1, I know...whatever)...my only road race podium (and near win) of the past few years was on a course with an ~7mile, relatively straight, gradual descent into the finish after the "decisive" climb. I was dropped by the lead group but was able to catch back on ~1/2 way down that descent. Judging by the way I passed (and then pulled up to the lead group) a significant number of riders (at least 6) who climbed better than me (riders who would not have caught back on otherwise...and some of them told me so after the race) I'm thinking the fact I was running Jet90s and an aero bottle on my aluminum Soloist helped a bunch in allowing me to catch back on.

Even 2 to 3 lbs. less weight wouldn't have kept me from getting dropped on the ~1 mile, 8% "climb"...I was easily 20-30s back over the crest. According to analyticcycling.com, 1 to 1.5 kg less mass would only have made me faster by ~3-5s, or ~15-22 meters further ahead over the duration of the climb.

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http://bikeblather.blogspot.com/

The group I ride with typically has a national champion and an Armed services champion who rode domestic pro for a few years. If I lose contact even for a much more than a few seconds its pretty much a done deal, but the ride is the best training around.

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Styrrell

It's like that here. Our Sat. group ride is 38 miles. The hill at mile 16 shatters the group. If you're not up front with the domestic pro and cat 1,2 leg breakers you're not going to catch up. The best you can do is create a chase group and race for 5th.

Yeah...we've got a couple of current and former domestic pros (one of whom rode the Giro not long ago), former Olympians, national champions of various stripes, etc. on our local group rides as well. You're right about that making for great training.

The thing is...I don't pick (nor run my best) equipment for group rides though. I save that for the guys I actually race against, who are none of those things I mention above...just average schmucks like me.

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http://bikeblather.blogspot.com/

Your n=1 aside, getting dropped on a climb almost always means you end up chasing solo, thus burning more energy than those aero wheels will save you. I know you probably said in jest but for one who pontificates about precision...

Burning more energy in reference to what? You seemed to have missed that even with 2-3lbs less weight (assuming I could get wheels that much lighter) I STILL would have been dropped (with equal energy expenditure) And to top it off, I'd have been much less likely to get back on afterwards (with equal energy expenditure...alls I can do is alls I can do ;-)

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http://bikeblather.blogspot.com/

Energy spent chasing back on. Big difference between going over a summit :20 versus :30 back in how much that equates to chasing. Like I said, maybe that worked for your n=1 example on an easy descent, but not in most cases.

Coincidentally, I did exactly the same comparison for myself yesterday. I also had a chat with Zipp support about the data. Here's what I gathered:

- The 303 graph does not have a vertical scale, but it is actually in grams, like the 404 graph.
- The horizontal scale on the 303 graph is not linear, but both it and the 404 graph have data points at the same yaw angles - 0°, 5°, 10°, 12.5°,15°,17.5° and 20°. Both are more like Excel line charts, rather than true graphs.
- The 404 FC testing was carried out using 23mm tyres and the same test conditions as the 303 FC test.
- The 404 FC clinchers and tubulars have similar aero performance.
- The claimed weight difference between the 303FC CC and 404 FC CC wheelsets is 59g.

My personal conclusion was that if, as Zipp claims, the majority of real-world riding is represented by the 10° yaw angle conditions, the weight difference is so low, the prices are roughly the same and since there are no huge hills in my area, I would be better served by the 404s.

Great info! Thanks.

My only take on this is that if one insists on running 23C or greater tires, then they're probably better off on the FC303s.

Uh Oh ;-)

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Styrrell

What's your glitch?

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http://bikeblather.blogspot.com/

See the following thread on Weight Weenies:

http://weightweenies.starbike.com/....php?f=3&t=97169

And in particular this graph submitted by Zipp.



So, as stated before, you gain 70 gms in weight, but you save 50 gms drag in aero.

  
Interesting...the comment I made at the time was based on Rappstars speculations only (that's all we had)...note the use of the term "probably". Glad to see there's finally data to show "what's what".

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http://bikeblather.blogspot.com/

Sorry for bringing up an old thread, but figured my question didn't need a thread of its own.

I am contemplating the 303 vs 404 myself. Ride mostly in flat terrain in the midwest but will be doing a few rides/races in CO. ~100g difference in weight between the two, however the 404 has slightly better aero (seems like drag is around ~100g difference at the largest delta). I am leaning towards the 404 as it will be the better all around wheel. However, would I be crazy to consider a 303/404 mix?

I don't think that's crazy at all. But, I "guess" that the 404 will be a tad stiffer because of the shorter spokes. That may make some difference on descents with switchbacks. So I'd choose the 404s.

So really, I'm probably not gaining too much benefit with the 303 front then? Drop a little weight (~50g) but lose some aero. I'm not worried about the handling aspect of the 404s. So maybe the 404s are the best option.

Hi!, and how about if I am short? 114 lbs and 5’3 weight? I have to doubt of buying a front 303 or 404 .. Rear sure to be 404. I am not sure if I can handle a front 404 (wind, etc) My bike is a Cannondale Slice RS..
Should be better a front 303 for me?

See if you can demo the wheel. Even at my lightest cycling weight 5'9" 143 pounds I had no problem with a 90 mm front wheel. But people have different levels of skill and confidences. I think you'd be fine with a 404 up front, but try to demo it first

A deeper rear wheel makes for better handling. Physics. If you were going to run an 808 or disc rear, I think the 404 would be a safer bet. But if you're going to go with a 404 rear, it opens up the question a bit.

Plenty of macho guys on here who swear they run a 90mm front with no problem, and yet go to a windy race and see who is actually in aero for the windy bits...not saying it doesn't happen, but I am saying this is the internet.

A 303/404 setup for someone your size is a very valid option. It might be slightly slower under some conditions, but it might be a lot better under some conditions as well. Take into consideration your average speed, the courses and conditions you race (and might race), and Plan B. We're not dealing with the theoretical optimum here, but the real world. Something that you're confident and comfortable on, that is still darn fast, is not a bad thing.

I have 303 and 404 but tubulars. I can't really tell the difference in handling...unless its super windy. I'm 5'8" and 140lbs.

I would go with the deepest wheels you're comfortable with. Even if you climb...I would take the 404 over the 303. The weight difference isn't that much.

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Cervelo S2/Zipp 404

As would I. I always felt like I was flexing my 303s quite a bit, but our team sprinter had the 404s and said he loved them because they were nice and stiff.

Anecdotal, but that was our experience.

The 303 should be stiffer. Its slightly wider and has more spokes than the 404.

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Cervelo S2/Zipp 404

Rims are more flexible?

Like I said, the 303s noticeably flexed and I'm not particularly big or powerful. Granted, this was the 2001-2002 version, so there could have been a layup difference. I've ridden Cane Creek Chronos with a 58mm rim and they were far stiffer, but different wheel and different lace up and all.

Wheel stiffness is a complicated thing.
Take two identical wheels, make the rim on one wheel stiffer, and it may end up seeming to flex more.

this is a good read:
http://www.slowtwitch.com/..._Stiffness_3449.html

In general I don't think any of the Zipps or Heds have any stiffness problems that are substantitive, and I am a big powerful rider (for short time durations), but your frame plays into the equation as well.

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

Here's my take on wheel depth coming from a 5'8" 132lb guy.

I can't ride a H3 once the weather station starts reporting wind gusts over 35mph. I prefer to go straight for a 50 or 60mm wheel at that point anyways so I skip the 80-90mms.

When it comes to road racing I find myself dabbing the breaks as I approach 50mph IF I am on the 50mm 7850 Dura-Ace wheels or 404s. I just do not like the way the bike moves around under me at those speeds so I am actually faster with a slower set of wheels because I can let it hang a lot more. Getting over the climb with the front group doesn't mean anything if you get dropped on the descent.

303's seem good enough for the pros during the spring classics. Doubt there is any stiffness/flexing issues. Plus if you want to run a wider tire I think you could do that on the 303 as it is wider than the 404.

Hi Aaron,

Andreas Klier (formerly a Cervelo TestTeam pro) agrees with you. I was recommending the 404s even on the mountain stages, but he explained to me that for him, in the autobus, the critical moments aren't on the flats or uphills (the autobus keeps reasonable tempo so the group can stay together), it's the descents. There are often a lot of sprinters in this group, who are typically heavier and have good bike handling skills, so they try to bomb the down hills as fast as possible to make up time when they can.

Andreas told me, coming around a switchback, there can sometimes be gusts. On a deeper wheel, he might have to touch the brakes to avoid going off the edge of the road - and lose the wheel in front. Then he would feel tempted to "ease up" in the next corners, possibly falling off the back and facing a looong ride to the finish alone.

So he chose the 202s in these stages, not for climbing, but for handling on the descents.

It was surprising to me at the time, but it made sense when he explained it.

Cheers,

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Damon Rinard
Engineering Manager,
CSG Road Engineering Department
Cannondale & GT Bicycles
(ex-Cervelo, ex-Trek, ex-Velomax, ex-Kestrel)

Talk him into 404 rear 303 front maybe =)

But yeah, deep wheels up front are just fine, until they aren't, and then it is really bad.

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

Hi Jack,

Yeah, he was talking about the front wheel only. 404s on the rear on those stages (and pretty much every stage).

Cheers,

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Damon Rinard
Engineering Manager,
CSG Road Engineering Department
Cannondale & GT Bicycles
(ex-Cervelo, ex-Trek, ex-Velomax, ex-Kestrel)

He is a genius!

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

The 2001-2002 Zipp 303's are completely different wheels than the new 303's that are out now. Obviously the Firecrest clinchers are completely different, but the 303 tubulars were redesigned in like 2009 to be 25mm wide. So you can't really compare stiffness of an old narrow 303, to the new ones.

Yup...in 2009 the 303 shape changed to a deeper wider shape. In 2012 the shape changed to the current FC shape which is slightly wider and rounder.

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Cervelo S2/Zipp 404