I don’t have much experience with aero wheels but I was hoping you guys could help me out.
I know BOTH weight and Aerodynamics are critical and helping you go fast. I am trying to figure out if it is better to purchase a Easton Tempest II - Pretty aero, easy to accelerate and very light 1265gm and stiff with excellent reputed quality. These can be purchase around $1400
On the other hand most discs appear to be relatively heavy 1000g to 1400g. Renn makes a very affordable disc the 575 at $520 and you can get either a clincher or tubular.
In some cases the Easton wheelset is the same weight as a whole disc! If the course is a bit hilly, which will help to shave off the most time?
DIsc is faster. Don’t forget a cheaper alternative. The aero disc cover. Places like www.wheelbuilder.com can cut one to cover any wheel, for a small fee. A lock-ring and chain whip and you are good to go. That’s a lot less than even a Renn. Which is a great wheel.
i dont presume to speak for Marc Cote, but when we visited the MIT tunnel just a few weeks ago, Marc was pretty darn adamant about a theory he was beginning to study, whic his that the disc wheel does not matter, that aerodynamically just the first 1/3 and top 1/3 of the bike really matter.
it had come up becaus i was prepping for the Fitchburg prologue/TT and it was kind of hilly, like 3% avg grade for 8miles.
i was actually the athlete getting tested in teh tunnel when we were talking about this so i was in the tunnel, out, in, out , in, scuttling around, and missed smeo of the dialogue.
our mit visit we video taped and is on youtube but i dont know if it was recorded.
for weight reasons, though not so much the issues as he felt the rear wheel disc was of minimal importance…he had recommended the 808s or even less.
now i lov my disc. and i didnt go with that theory of his. i used my disc in just about all conditions unless a major hilly course maybe like harriman/bear mtn.
i like the weight of it in the flats.i like the sounds. i like the way it rolls. it feels fast.
but like anything else, the tunnnel sometiems is the only place you can prove that out.
and he now runs teh colorado new tunnel. so dont discount taht. someone should email him.
and i do reasonably in tt’s, won the NJ Masters State TT championship, and won NYS as well this past weekend. so trust me, i’m tring to get as fast as i can. i didnt buy it.
but i did buy the clinchers over tubular argument of rmy 999disc set. fast.
I thought I remember seeing or hearing that the front wheel is 70% of the aero difference. So getting just a disc compared to a race wheel**S** would be no question.
Glad to see this topic pop up as I was going to pose a similar question as the initial poster.
I currently have a HED Stinger 60/90 setup, but I am looking to improve. I am looking at either a combination of 90/90, 90/Renn disc, 60/Renn Disc or HED 3/Renn Disc. Money ($200) is a big factor, although selling the current 60/90 (which are 6 months old and perfect) would cover at least 80% of the costs of the HED 3/Disc set up. Or at least I hope it would.
Is there any reason not to get the HED 3/Renn combo for non-mountainous racing? Is that set up going to be markedly faster than a 90/90 set up (?), which might be a bit cheaper and involve less selling/buying/shipping costs. I know speeds matter in these things so lets consider 58:30-59:00 for 40k, 2:23-2:28 for HIM.
My understanding is the H3 is only faster with certain types of forks.
I also remember reading the from wheel makes the most difference in aerodynamics. Maybe a deeper aero wheel should be used in from and a light rear wheel to aid in acceleration. It would be intersting to see if a 90mm or 100mm in front and a 50mm in back vs the other way around. Hmmmm…that would be an intersting experience.
Since you are riding Hed wheels why not call / email them and ask their opinion. I live locally and have bought two sets of wheels from them (Hed 3 and Stinger 60/90). In the end they said there was very, very little difference in any of the combos you are talking about. A few (3-5) seconds per 40k tops-if that. Based on talking with them (including Steve) I decided on a general set of training / race wheels that I can use all the time (Hed 3) and a set of wheels for IM (Stinger 60/90). The only real reason I got the Stingers though is because I wanted them. No speed difference in their opinion over the Hed 3 set. Maybe they are a bit more comfortable over a long course event. In the end I don’t think they will say either way that one set is faster than the other. If money is an issue I would stick with what you have.
Give them a call or send an email. The great thing about Hed is that they wont tell you a bunch of BS just to sell you wheels. Very good and honest people.
Not even a question, aerodynamics over weight in a TT/Tri. Unless there is significant hills, where weight becomes more of an issue.
UNTRUE. It is a combination of weight and aero regardless. A concrete aero wheel is not as fast as a carbon set with same cross section. Hed will take calls as another poster stated, and there are - generally - minimal differences between a disc and Stinger 90 or 808.
The aerodynamics of a wheel set does vary from rider to rider, and frame to frame (including fork). For some a Hed 3 is bad because of air flow challenges with fork setup, and a spoked Stinger 60 may be prefered. The rear end sees less that 30% of the drag as the front, so impact is often reduced.
Watch the classifieds, you may find a aeroset for your pricebreak, a lighter deeper aeroset would offer more overall benefit versus a disc and your current from wheel.
Not even a question, aerodynamics over weight in a TT/Tri. Unless there is significant hills, where weight becomes more of an issue.
UNTRUE. It is a combination of weight and aero regardless. A concrete aero wheel is not as fast as a carbon set with same cross section. Hed will take calls as another poster stated, and there are - generally - minimal differences between a disc and Stinger 90 or 808.
The aerodynamics of a wheel set does vary from rider to rider, and frame to frame (including fork). For some a Hed 3 is bad because of air flow challenges with fork setup, and a spoked Stinger 60 may be prefered. The rear end sees less that 30% of the drag as the front, so impact is often reduced.
Watch the classifieds, you may find a aeroset for your pricebreak, a lighter deeper aeroset would offer more overall benefit versus a disc and your current from wheel.
The concrete wheel would be as fast when up to speed and even faster down hill! Stopping and turning might pose some problems though, but I doubt you would be worried much by cross winds
I would be worried about the wheel holding together under heavy vibration, and it would ride somewhat rough, though very stiff!
My understanding is the H3 is only faster with certain types of forks.
The “chuffing” to which this rumor came about has never been shown to have a significant impact on speed. Though if you can get your hands on a proper fork, it can’t hurt.
It sounds like if the course is very flat, weight is much less of a concern and a disc is the way to go. I am getting the impression that if the course is hillier the more weight is going to be a factor. Perhaps the best compromise is a really light disc?
Other than really hilly courses, when is a disc truly a disadvantage? What type of wind conditions?
Not even a question, aerodynamics over weight in a TT/Tri. Unless there is significant hills, where weight becomes more of an issue.
For some a Hed 3 is bad because of air flow challenges with fork setup, and a spoked Stinger 60 may be prefered.
Interesting. Don’t mean to hijack this thread.
I posted a thread y’day headed …“Hed H3 Carbons and speed wobbles”.
What would be your thoughts on a Hed H3 Carbon set-up with Real Design aero HP Carbon Forks.
Continental Sprinter Tubulars 22mm ( 27’).
If you could add your thoughts on my thread I’d appreciate it.
I can’t tell you what is ideal for your set-up. All I know is that some forks with a Hed 3, you can hear a “whoop-whoop” of the spokes, and that is wind turbulance stealing speed. Also, smaller builds (body) have different effects on aerodynamics. Broader shoulders create greater wind deflection downwards in comparison to those slimmer. Thus, in a wind tunnel condition the same bike set-up shows wildly different readings, and a front wheel choice would offer different benefits.
As for Hed3, Macca had his choice of wheels for Ironman, he chose to run one on the rear, not the front (Stinger 60) - he spent plenty of time in the wind tunnel.
