tri spoke vs disk/deep wheel

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milehighcyclist
Posts: 32
Joined: Sun Jan 12, 2014 12:41 am

by milehighcyclist

what are advantages/disadvantages of tri spoke vs a rear disk or a wheel like the zipp 808?

what about a tri spoke in the front vs a zipp 808 or 404?

seems like most pro teams are moving away from tri spoke wheels and going to wheels like the zipp 404 in the front and a rear disk, curious to know why that is

commendatore
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Location: North Carolina

by commendatore

A rear disc is always faster. Unless it's significantly uphill, or really windy. But even then, probably still faster.

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mjduct
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Joined: Tue Dec 27, 2011 2:19 pm

by mjduct

The choice for front is basically as aero as you can go with rider comfort/ steering control based on conditions taken into account.

milehighcyclist
Posts: 32
Joined: Sun Jan 12, 2014 12:41 am

by milehighcyclist

is a tri spoke more aero in the front than say a zipp 808?
which would handle better in crosswinds?

hna
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Location: Norway

by hna

Juanmoretime wrote:As for what the pro's ride always keep in mind they ride what they are paid to ride. If they were paid to ride a pig they would ride a pig. I'm sure if the pro's could ride what they wanted we would see different equipment verses what we see now.


That's true to some extent. There were a ton of rebadged Lightweight discs in the Tour for example. You have also had Team Sky riding the three spoke Hed front wheel up until this Tour even though they are not sponsored. They rode a wider three spoke prototype from Pro in the Tour.

davidalone
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Joined: Fri Feb 10, 2012 4:27 pm

by davidalone

The trispoke is the best choice in the front if you're facing variable wind conditions.

you need to understand Yaw and it's relationship to aero. Aero wheels don't give you the same watts savings at every different place on the course, which is dependent on wind direction and the speed you are travelling at. See the HED website for an explanation for yaw angle and their yaw angle calculator. Which is why Knowing the wind conditions at your start time is critical at the pointy end of things to do a really good TT.

Different companies also have different design philosophies with respect to yaw. baseed on this test: http://triathlon.competitor.com/files/2 ... Vision.pdf

Zipp has designed their wheels to dominate at low yaw, but stalls out earlier than the others- notice the graph when the drag increases sharply after 20 degrees. ENVE, HED and the bontrager aeolus aren't outrightly as aero but they will still mantain their performance after 20 degrees of yaw. whether this is a good thing for you will depend on your course conditions.

Back to the trispoke- according to HED ( and other) tests: (http://www.hedcycling.com/h3/default.as ... 3_Clincher) it has the most 'consistent' performance across yaw angles, so if you have a technical TT with lots of direction changes, wind blowing all over the place.... the trispoke may be a better bet than a deep wheel like the 808. it is a versatile wheel, which is why it has been around for so long. It is certainly not the most aero, but if you're not sure, it is a good bet. I don't own a trispoke, so I can't comment on the handling benefits of putting one up front compared to a deep wheel. as mentioned, the shallower the wheel, the less affected it will be by crosswinds as well.

the disc is ALWAYS more aero on the rear than the trispoke, having a disc on the rear can add some stability in crosswinds as well. you will probably only ever see a trispoke rear selected over a disc in races where discs are banned ( e.g. Ironman world champs in Kona,) or on the track.

The teams are NOT moving away from the trispoke- look at this year's Tour TT pictures. Sky, Cannondale, Katusha, Astana, all rode trispokes in some form or other.

hna
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Location: Norway

by hna

Scarponi actually rode a four spoke rear in the Tour.

Edit: It might have been his spare bike.

Kasparz
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Location: Latvia

by Kasparz

hna, many riders have used deep dish wheels or trispokes rear even on world tour races where disc would be faster.
Personally I use HED Stinger FR Disc and pre-firecrest 808 front with Vittoria Crono CS 22mm(21mm real) on both wheels.
What I can tell you that I had excessive research about both wheels. HED Disc was fastest disc, beating both Zipp Sub and Super 9, other brand discs were slower. HED structurally are spoked wheel with carbon cover, and that makes HED more lively on road. Flat discs are pain to ride on rough surfaces, lacking any road feel. HED disc feels like normal spoked wheel. i bought mine from Highroad team. My disc was used by one of the best TT riders in the world. Martin, Wiggins and many other TT specialists have used HED Stinger disc while they had options to choose from Hed, Zipp or Pro discs. As the HED Stinger disc is very wide, be sure not to use too narrow tire and make sure wheel hides behind seattube, otherwise it will stick out from seattube and decrease aero benefits.
Front wheel I'm using pre-firecrest due to the fact that pre-fc zipp can accumulate narrower tyres. As specified by ZIPP engineer, ideal tyre width for pre-fc 808 is 21mm. Pre-fc is faster than fc in low yaw angles, narrower tyre make it even more faster. HED H3 is fast with 19mm tyre at very, very low yaw angles. In real world 808 is faster. Old 1080 might be even morre faster in calm, straight and flat course, but it is a pig to handle if you have to take a corner. Probably not far from having disc up front.
Talking about discs and frames, it is also good to have understanding what type of disc(torroidial, lenticular or flat) is best for your frame.

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TwiggyTN
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by TwiggyTN

This. That's some good 411 right there. Thanks!

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mjduct
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Joined: Tue Dec 27, 2011 2:19 pm

by mjduct

Kasparz wrote:Talking about discs and frames, it is also good to have understanding what type of disc(torroidial, lenticular or flat) is best for your frame.


You seem to have a firm grip on the subject,

Can you share the differences and which frame features would benefit from each type?

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HillRPete
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by HillRPete

Kasparz wrote:Front wheel I'm using pre-firecrest due to the fact that pre-fc zipp can accumulate narrower tyres. As specified by ZIPP engineer, ideal tyre width for pre-fc 808 is 21mm. Pre-fc is faster than fc in low yaw angles, narrower tyre make it even more faster. HED H3 is fast with 19mm tyre at very, very low yaw angles.

Do you have any idea how much difference 2-3mm tyre width on the front wheel makes? I always read narrow tyres are faster, and it is intuitive, just how much is the question, since narrow tyres are an increasing trade-off as the conditions get worse (weather, surface, turns).

The November Bicycles article linked from another thread suggests a difference of at most 5s/40km. I'm wondering if rolling resistance gains wouldn't cancel that out easily in everything other than maybe perfect conditions.

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