There has been a post on the board the last couple of days about the best rear racing wheel being a $400 wheel with the wheelbuilder.com aero cover on it. What kind of a difference can one expect in feel and speed from an aero cover on the back wheel. I have a set of 50mm Cosmic Carbone wheels and have been happy with them but am intrigued by what a rear “disc” wheel would be. I am doing a few 1/2 races and IM Moo this year, if that makes any difference.
for a basic idea
go to HEDCYLING.com and look at the Jet disc aero data compared to a jet 60
see how the drag keeps going down the more wind there is?
thats pretty cool
and yes it has bee confirmed that a wheel cover behaves comparably
and yes it has bee confirmed that a wheel cover behaves comparably
I’ve been saying that for years, but yesterday someone called me out on it. Any idea who confirmed it?
one place that has hard numbers is biketechreview.com
but you have to pay for the raw data
.
Cool, ta for the info, although if you come across any that’s free, please post that up here too!
Cool, ta for the info, although if you come across any that’s free, please post that up here too!
I believe that Jens posted here on ST that according to his “measurements”, his 808 wheel with a cover was faster than any other “true” disc he’d ridden. It’s not wind tunnel data…but it’s fairly reliable…AND it FREE!
Thank you and Horah!
Who would ever listen to what Jens has to say! ; )
Similar question. I am trying to decide on a wheelcover for IM CA 70.3. Since the Oceanside course has quite a bit of climbing on the backside, not sure the weight penalty is worth it. Anyone else have a recommendation?? I ride Zipp 808 rear and 404 front.
bump…
I’ve used wheelcover on a Cosmic Carbon.
It works fine, but the non driving side is not perfect for a wheelcover on this wheel.
I’ll do IM LP this year, but I’ll remove the wheel cover, since the weight penalty seems too bad for me on such a route. (plus I don’t want to test it on wet day…)
sigh
I miss Jens
.
How easy are these to put on? Has anyone heard of one coming off???
Eugene
Real easy to put on. Entire job might take ten minutes. No reason why one should come off.
who is jens?
A very fast TT’er from Denmark (I believe) who is also an engineer.
i just used a wheelcover for the first time. at roady’s suggestion i ditched my disk and went with a covered 808 rear, and road my fasted tt by a lot (other factors played into this so not just the wheel).
it took about 15 minutes to put on the first time, which includes pulling off & reinstalling cassette. i ordered my cover with fasteners but only used two to make sure the cover would stay on (paranoia) and taped over the rest of the fastener holes. also taped the cover to rim for a smooth surface. pretty easy really, and i have zero tech skills.
and to the poster about weight, please stop with the ‘how much penalty will the extra 100 grams cost me’ questions. the answer is zero on pretty much any tri course - sans very few. if there’s any penalty at all it will be more than made up on the other 98% of the course.
who is jens?
The person he misses. Please, at least try to follow along. 
-Jot
search the screen name. smart dude. gave up cycling for his family. he was an incredible source of information.
there is no such thing as weight penalty… not for a cover over a 808… it s about 350gram and on a course like Oceanside… simply impossible to feel and IT isnt HILLY … you might think it is but the only time weight will affect your performance is on a very step uphill TT with no downhill or flat… and even then, the ‘‘penality is extremly small’’
it s a no brainer… disc cover for sure at oceanside…