What carbon wheel depth combination?!

Discuss light weight issues concerning road bikes & parts.
Post Reply
Posts: 27
Joined: Wed Aug 01, 2012 10:20 am

by Guyeclipse

Hi there Weight Weenies, I need a little help here.I am in the throws of possibly purchasing some carbon wheels for time trials and the occasional casual ride. I am looking at tubulars, and I still want them to be light, so I don't want to go too deep. Also I am pretty light at about 60-65kg and where I live there are some pretty prominent winds and I don't want to be blown around too much. My steed of choice is a Felt AR, so I already feel the crosswinds a bit. So here are the options, anyone got any ideas?

50mm F, 50mm R
50mm F, 60mm R
50mm F, 80mm R
44mm F, 80mm R

Please help!

by Weenie

User avatar
Posts: 7045
Joined: Sat Jun 19, 2004 11:08 am
Location: Urbana, Illinois

by Juanmoretime

I can't say if its true or just marketing but the Zipp 404 Firecrest are supposed to be extremely aero and designed to handle better in the wind. On my tt bike I train on Easton EA90 Aero's and race on a Zipp 808 front, non Firecrest since it is too wide to work with the fork on my tt bike and a disc in the back. If you do look at the Firecrest make sure it will work with your fork and rear stays.

Posts: 1427
Joined: Fri Dec 24, 2010 9:37 pm
Location: it's raining, it must be uk

by sungod

what wind speeds and road types?

i'm c. 76kg, on 53mm rims in 35+kph winds with gusts it's generally ok on the flat, but fast twisty descents, especially with traffic, can be nasty and i slow way down; it can also get interesting if i catch air while in a side wind, the bike gets blown off-vertical under me

if you'll be riding windy conditions, i'd go with a smaller front - zipp claim their firecrest 202 performs as well as older-design 40-50mm rims and they should handle much better in the wind

Posts: 409
Joined: Tue Oct 28, 2008 9:00 pm
Location: London, United Kingdom

by parajba

I'm 67kg and race on a pair of pre FC 404s tubs. I had several occasions where I had to slow down because I felt not safe. I race on a Cervelo S2 which doesn't help. I live in the UK (London) and for the record I'm a good descender / good technique. For comparison, same wheels but different frame (Cervelo R3) never had any issues with speed and instability...So perhaps it's not the wheels.

in the industry
Posts: 3428
Joined: Sat May 12, 2012 7:25 pm
Location: Glermsford, Suffolk U.K

by bm0p700f

In strong gust shouldn't we be slowing down anyway so it only a problem if you are trying to be a hero and arry on like there is no wind.

Posts: 1482
Joined: Fri Oct 28, 2011 3:25 am
Location: United Kingdom of Great Britain and Northern Ireland

by Valbrona

There is more point to using a deep section front rather than back. Most air is 'dirty' by the time it hits the rear wheel.

Posts: 105
Joined: Sat May 12, 2012 5:48 am

by Brandonnie

404 front 808 rear.

Posts: 158
Joined: Mon Jul 18, 2011 4:37 pm

by xjbaylor

bm0p700f wrote:In strong gust shouldn't we be slowing down anyway so it only a problem if you are trying to be a hero and arry on like there is no wind.

It isn't that easy to predict when a big gust of wind is going to hit. If you were to slow down for any threat of strong wind gusts in my area you just wouldn't ride in the spring or fall. Even at 15mph a 30+ gust can be pretty scary, especially on deeper rims.

Posts: 27
Joined: Wed Aug 01, 2012 10:20 am

by Guyeclipse

I don't quite have the luxury of a set of firecrests, currently I'm looking at a set of Chinese tubulars so I think I need to go shallower than what you guys suggested as I am aware of he merits of the FCs. I won't be riding these down hill often as the time trial courses are either flat or descents that are negligible in length. I live in Auckland which is susceptible to the occasional strong crosswind so I really can't go too deep. And as I said I ride a Felt AR which I already get pretty blown around on in the occasional strong wind.

I had a look through some photos of the '11 Tour, and noticed Cav's wheel choice was a 50mm front and 60mm rear. If its good enough for the best sprinter in the world, it will be good enough for me. Even though he is sprinting as opposed to time trialling on them.

Thanks for all your help! If anyone rides this combo, please can I have some of your feedback.

Resident master of GIF
Posts: 3169
Joined: Mon Jul 18, 2011 2:44 am

by nathanong87

front disc and rear 50mm. change the game.

User avatar
Posts: 1289
Joined: Sun Nov 02, 2003 6:48 am
Location: Central USA

by tommasini

Not forgetting the OP's intended use, my 2 cents is that I am running 50's on my two road bikes for training/group rides/racing. It's moderate rolling terrain with some flats around here. I was once tempted to try 80mm deep rims on the road (offered a great price). So while debating I checked out Zipps chart (not for current rim models but still a good side by side of similar designed wheels) showing time savings when going up from shallower to deeper, including combo's of say a 404 front with 808 rear.

http://www.spinlitecycling.com/ZippAeroEdgeFlyer.pdf" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

The time gain (watts reduced) running the next size deeper rear was very, very small.....yet you gain well over 100 grams in weight at the rear rim. Run the next size deeper both front and rear (say 808s vs 404s) the weight gain is like a half a pound all at the rims. I then checked out pics of what the pro's were riding last and this year at the major stage races.....very rarely is it greater than 50's. And when I did see an occasional sprinter bike with a larger than 50's wheel it was the rear only.....and then after losing the sprint that day, then next day in similar terrain that rider was back to 50's front and back again.....

My take away, if you do steady rides in good light wind (TT/solo or small group friendlies) then go for it as a special once in a while wheelset. If you have rides with accelerations, wind variables, want to use most days, etc I'd stick with 50's for day in and out use in all sorts of conditions.

Posts: 27
Joined: Wed Aug 01, 2012 10:20 am

by Guyeclipse

Thank you Tommasini that was very helpful and will definitely be reconsidering my options here. Looking at that I might go to 50mm front and rear, because not only is it a bit cheaper, it also looks a lot more uniform, for very little aerodynamic hinderance.

And I am not too keen on running a super deep rim on the front and shallow on the back, because not only does this adversely affect handling, it also looks ridiculous. And not the good ridiculous. I mean I want it to look cool too right? :)

Posts: 628
Joined: Wed Jan 12, 2005 6:04 am
Location: USA

by Bridgeman

I think the Enve 6.7 looks very cool.

by Weenie

Johnny Rad
Posts: 1809
Joined: Fri Feb 17, 2006 6:22 am
Location: Zion

by Johnny Rad

I've got both 32mm and 46mm Reynolds wheel sets.

The deeper wheels are my everyday set. In all but the most extreme winds, they're fine. In extreme winds, it's pushing me sideways as much as my wheels. I just don't worry about which wheels are mounted when its windy.

I think you'll be fine with any of your choices.

Post pics of your new wheels when you get them.

Post Reply
  • Similar Topics
    Last post