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HED Je9 vs Zipp 808
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Can someone point me to a chart that shows a drag comparison for the two (hopefully done by a third party). I'm working on my cost vs benefit comparison...

Thanks!
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Re: HED Je9 vs Zipp 808 [10-4] [ In reply to ]
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Tour magazine just make a very interesting study, in conclusion the zipp was the fastest wheel. They post a pic of the drag data somewhere in this forum. If you have and iPad o Iphone try to download the app for the online version of the magazine I highly recommended
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Re: HED Je9 vs Zipp 808 [10-4] [ In reply to ]
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Tour Magazine had a test with both those wheels (Jet 9 2011 and 808 Firecrest) last year. I think it's available at Tour's site, but else you should be able to dig it up with a bit of search here on the forum. It's been mentioned and linked to several times.

IIRC 808 beat Jet 9 by 2-4 watts depending on yaw angle, though rotational drag wasn't measured, which could skew the results a bit both ways - probably not by much though, as the wheels/spokes are pretty equal. The test was done with a 23mm Continental tire (GP4000S, I think).

Edit: Luis B beat me to it.
Last edited by: MTM: Feb 7, 12 9:00
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Re: HED Je9 vs Zipp 808 [10-4] [ In reply to ]
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I have the 808s, but I didn't really care about costs too much. I strongly suspect that the results of a cost:benefit analysis would yield that the HEDs are better because of their lower price.
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Re: HED Je9 vs Zipp 808 [10-4] [ In reply to ]
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I have had both. Currently use Hed jet 6 and 9 (clinchers-- box rim with carbon fairing). Have to say I liked my Zipps more. Although the Zipps had an alum rim, the carbon fairing was structural and absorbed a lot more road vibration. The firecrests have got to be sweet..........
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Re: HED Je9 vs Zipp 808 [fastwiley] [ In reply to ]
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I had a Jet 9 (front only; disc rear) and decided it flexed too much for my taste... most glaring example was on TT turnarounds my computer magnet would hit the fork sensor and the brake would rub. Not a huge deal for most courses which are predominantly flat & straight, but it annoyed me enough whenever cornering was required that I replaced it w/ an older 808 and definitely like it better. Same # of spokes (18), but the deeper rim on the Zipp results in a stiffer build than the shallower rim + fairing of the Hed. For reference, I weigh 175-185ish (depends on the season).

Used, the price diff was only about $125-150 (don't remember exactly; pretty much broke even re-selling the Hed and the 808 was roughly half what the new FCs go for).
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Re: HED Je9 vs Zipp 808 [OneGoodLeg] [ In reply to ]
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 >but the deeper rim on the Zipp results in a stiffer build than the shallower rim + fairing of the Hed. For reference, I weigh 175-185ish (depends on the season).

Your HED may have been flexy, but wheel + fairing combos can be made as stiff as you can make a spoked wheel, which is really, really stiff.

For what it's worth I race my Jet9 in crits, and haven't noticed any stiffness issues. It's just fine in field sprints or cornering at 30MPH.
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Re: HED Je9 vs Zipp 808 [OneGoodLeg] [ In reply to ]
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I'm just doing the force simulation in my head here but I think if the wheel is causing your magnet to hit your sensor, that in fact it would imply the wheel is stiffer, causing flex in the fork. A flexier wheel would reduce the problem. Similar to brake rub issues on rear wheels.

thoughts?

175lbs here and never noticed a stiffness problem with an older, narrow jet 9.



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
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Re: HED Je9 vs Zipp 808 [trail] [ In reply to ]
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trail wrote:
For what it's worth I race my Jet9 in crits, and haven't noticed any stiffness issues. It's just fine in field sprints or cornering at 30MPH.

same here, and bigger dudes can always go for the stallion build for some extra spokes.



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
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Re: HED Je9 vs Zipp 808 [jackmott] [ In reply to ]
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Re: HED Je9 vs Zipp 808 [jackmott] [ In reply to ]
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well, perhaps I can see what you're getting at conceptually, but I certainly haven't given in to any thoughts of trying to actually calculate the math/physics... I just noticed the problem when I rode it, and then futzing around in the work stand afterwards I could simply pinch/squeeze one side of the wheel rim against the opposite fork leg with my fingers and deflect the shit out of it.

I've had other wheels where it was obviously a case of play in the hub/axle that allowed the wheel to flop off-axis, but this definitely appeared to be flex in the spoke/rim assembly. Whatever it was, I get much less of the same deflection using the same fork with my 808 (which, ironically, does have a little play in the hub, but overall the wheel resists flexing out of plane as much). It just seemed pretty intuitive to me that if you visualize the Hed without the fairing, you're left with an 18-spoke wheel on a relatively shallow rim... which would surprise nobody if you said that was flexy. The fairing just gives the appearance of a deep rim so 18 spokes doesn't seem like so few. Additional spokes like the stallion build would've obviously helped, how much I don't know.

And besides the number of spokes and stiffness of the rim itself, if you look at the Zipp vs Hed construction the other factor at play is the triangulation of the spokes in the lateral plane... the Hed has a flangeless hub and of course the spokes are also longer as a function of the shallower rim, so the spokes brace the wheel from a much shallower angle than the Zipps when viewed from the front. Seems like that has to play a role, doesn't it? Maybe it has less to do with the supposed stiffness of the rim itself and is more a function of the length of the spokes?

I've built a couple wheels before so I realize the whole is greater than just the sum of the parts, so maybe I just had one that didn't add up for some odd reason (spoke tension?) and my rationalizations about the design are misplaced, but I swear the difference was pretty obvious holding them in your hands side by side.
Last edited by: OneGoodLeg: Feb 7, 12 14:30
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Re: HED Je9 vs Zipp 808 [Runless] [ In reply to ]
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I have no idea what this means, but it sounds impressive.


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Re: HED Je9 vs Zipp 808 [Runless] [ In reply to ]
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Auf Englisch, bitte!
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Re: HED Je9 vs Zipp 808 [10-4] [ In reply to ]
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Awesome, thanks everyone!
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Re: HED Je9 vs Zipp 808 [OneGoodLeg] [ In reply to ]
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The previous post with the image didn't show. And I don't speak German, but one hardly needs to, there is graphs and watt calculations. There may be an english version floating around by now though...

23mm Conti tire, yaw from 0 out I believe
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Re: HED Je9 vs Zipp 808 [Runless] [ In reply to ]
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Is the Mavic Carbone really that bad? I was thinking about putting some on a road bike because I liked the way the new ones looked with the Exalith brake surface. But holy cow....
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Re: HED Je9 vs Zipp 808 [10-4] [ In reply to ]
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i beleive the cosmic carbon also features in a drag chart put out by zipp and came up equally poor. i guess that´s the difference between old school wheel makers who just build a sharp deep section rim profile and call it aero, without necessarily testing, and companies like zipp and hed.

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Re: HED Je9 vs Zipp 808 [Runless] [ In reply to ]
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So for the chart with watts at 30/40/50 kph, what do the respective watt numbers mean?
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Re: HED Je9 vs Zipp 808 [10-4] [ In reply to ]
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So- summarizing:

the Zipp 808 is the bees knees. Fastest wheel out there. Buys you 4:46 sec in an IM.

the Hed Jet9 is close, a few watts slower, except for that 15-25degree range where it's not even close. nothing is except the discs.

The 404 is right there with the 808 out to about 14 degrees.

The Hed H3D is right there with the best of them out to 10-11 degrees, and then loses it. (wonder if the position of those 3 spokes matters... or how the drag compares when the wheel is spinning vs a traditionally spoked wheel?????)

I don't know what a 'fast foward' wheel is. is that a euro product?


Interesting other note, is that I've always heard that the H3's are build like tanks. Very strong and stiff- but it came out as the least stiff wheel in the test set. ???
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Re: HED Je9 vs Zipp 808 [mrwoodhouse] [ In reply to ]
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mrwoodhouse wrote:
So for the chart with watts at 30/40/50 kph, what do the respective watt numbers mean?

it will be watts of power required to maintain the bike at that speed...assuming the only force acting to slow it down is the aerodynamic drag of one wheel and assuming a certain air density. they say "influence of sidewind is factored in" (see english version of the article, p96 here http://www.tour-qtr.com/epaper_4_2011) which is kindof ambiguous other than that they probably didnt use the 0 degree yaw drag numbers.

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Re: HED Je9 vs Zipp 808 [morey000] [ In reply to ]
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morey000 wrote:
I don't know what a 'fast foward' wheel is. is that a euro product?

yes, been around a while but pretty rare to see them http://www.ffwdwheels.com/products/wheels/

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Re: HED Je9 vs Zipp 808 [10-4] [ In reply to ]
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10-4 wrote:
Is the Mavic Carbone really that bad? I was thinking about putting some on a road bike because I liked the way the new ones looked with the Exalith brake surface. But holy cow....
The Tour test seems to say it's 18.8mm wide. If they tested all the wheels with a 23mm tyre, then of course an 18.8mm wide rim is going to look terrible compared to the wider rims.
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Re: HED Je9 vs Zipp 808 [Steve Irwin] [ In reply to ]
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Steve Irwin wrote:
10-4 wrote:
Is the Mavic Carbone really that bad? I was thinking about putting some on a road bike because I liked the way the new ones looked with the Exalith brake surface. But holy cow....

The Tour test seems to say it's 18.8mm wide. If they tested all the wheels with a 23mm tyre, then of course an 18.8mm wide rim is going to look terrible compared to the wider rims.

Fair enough, but it's almost as if they needed to show more chart than needed so the Mavic didn't disappear all together.
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Re: HED Je9 vs Zipp 808 [morey000] [ In reply to ]
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morey000 wrote:
So- summarizing:

the Zipp 808 is the bees knees. Fastest wheel out there. Buys you 4:46 sec in an IM.

Kind of what I'm gathering. Is that 4:46 number comparing the 808 to a box-section wheel?
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Re: HED Je9 vs Zipp 808 [10-4] [ In reply to ]
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10-4 wrote:
Fair enough, but it's almost as if they needed to show more chart than needed so the Mavic didn't disappear all together.
The Mavic is the narrowest rim in the test, apart from the Citex, which is even narrower and performed worse. Looking at the English language version, they used a GP4000S tyre with every wheel. It's basically a test stacked in favour of the widest rims, it would all look very different if they put a 20mm supersonic on every wheel, particularly as the yaw angle increases, where it becomes very disadvantageous to have a wider tyre relative to the rim.
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