Disc Wheel Vs Deep Section | Which Wheel Should You Race With?

Disc Wheel Vs Deep Section | Which Wheel Should You Race With?

– Choosing the right wheels
for race day can be so tricky and rightly so because
they can have a huge affect on your performance. – Yeah, it is always a
question of balancing the aerodynamic advantages
of a deeper wheel, against the slightly lighter weight and potentially even the greater stability of a shallower wheel. – Well, what about a disc? I mean, we see the pros riding them they look fast, but are they right for us and when would we want to use them? How do they compare to
a deep section wheel? – Well with the launch of
our partners new disc wheel the Enve SES disc we’re gonna
be putting it up against one of their shallower
wheels, the Enve SES 7.8 to see how they compare, but
also to help explain to you how and when they may
suit different riders and different courses. (electronic noises) (electronic music) – Before we go any further, let’s take a walk down memory lane. Back in the mid 1980’s, Francesco Moser broke the 1 hour record indoors on a track, using both a front and a rear disc wheel. Now this was more or less the first time that we’d seen disc wheels in use and in quite some style
so it’s not a surprise that it made some impact and it suddenly increased the
popularity of the disc wheel. Especially amongst tri-athletes,
as well as our dedicated time trialling friends. – Well it seems that
tri-athletes are quite often unsure as to what wheel
type they should use, to start off with I
thought we’d talk through the deep section wheel
and the benefits behind it and what makes them so fast. You can see that it has
this air foil shape to it and that helps it to pass
through the air more smoothly when you compare it to something like a shallow box shaped rim. When you think about
it, you’ve got the tyre as the leading edge, that
cuts through the air, and then the air then passes over the rim and the idea behind the deep section rim is it allows they air
to pass over smoothly and bring it back together
in a clean fashion, which, when you compare to a
shallow shaped rim again, or a shallow box shaped
rim, it can’t do that. The air comes back together
in a messy fashion, more turbulent, and that creates drag. Secondly, deep wheels can
almost create a sail affect. So when the air flow
follows over the wheel, at an angle it can almost
create a slight forward thrust. So actually a wheels own drag can decrease as the wind angle and
wind speed increases. Obviously to a point,
but we’ll get into that a little bit later on. – Now on to the disc wheel,
the dawn of all aero wheels. The wind passes smoothly over the surface, cause there’s no break in the surface so you’re not gonna have that
turbulent affect, or any drag. As for that sail affect
that we mentioned earlier, you can see it doesn’t really
get any better than this. Lets get this show on the road, I think it’s time we put these
wheels through their paces to find out whether one
is faster than the other from either of us. – So we’re gonna be doing
a flat 5 km time trial along the Queen Ka which
is part of the Ironman World Championship course and it’s very famous for its strong winds. In fact today, it’s
recording around 13 km/h coming at us from around a
north westerly direction. A nice crosswind to try
the wheels out with, but nothing too severe. – Well Mark, you’re gonna
be holding around 300 watts, and I’m gonna be trying to hold 200. (tense music) – Okay, so starting off
with the deep section wheels flat time trial, here I come. – Okay it’s my turn to test
out the deep section wheel on the flat, here we go. (competitive music) – Okay I’m going full
aero now, my second run, on the disc wheel. Let’s go. (tense music) – Okay, same again still holding 200 watts but this time I’ve got the
disc wheel in the back, so let’s see how fast I can go. (tense music) – Well that was good fun, we were absolutely flying
along there weren’t we. – Yeah, it felt pretty good. – Yeah well my time on
the deep section wheel was 7:02 seconds. – [Heather] While I was
7:50 seconds on that one. – [Mark] And then on the disc wheel, I was 6:49 seconds, so
considerably faster actually. – [Heather] Yeah, same, well I was quicker with a 7:43 on this. – And I have to say, I felt like I was really getting that sail affect from the disc wheel.
– yeah that I was flying along
and it just felt so easy so smooth. – Yeah I mean it’s the first
time I’ve ridden a disc, and I loved it, felt pretty cool. – Obviously not all
courses are pancake flat, like that section of road
that we’ve just used. That is where things start to become a little bit fuzzy and
confusing for people, because a disc wheel obviously
has more material on it, so they tend to weigh a little bit more. I mean if you take this Enve SES disc, it’s new disc wheel,
it’s a fraction heavier. It’s remarkably light but
still around 1125 grammes. – Where as this SES 7.8 deep section wheel weighs around 950 grammes
so the question is, do you want to be
carrying that extra weight and what difference will it make when it comes to a climb? Well we’ve come out of the town of Kona to this hill here, and
we’re gonna be riding a distance of approximately 3 km that’s got an average grading
of six to seven percent. – We’re gonna be making sure
that we start and finish at the same point each time
and given that it is a hill, we need to make sure that
we get up over that hill so we’re gonna bump up
our upper fraction now. So I’m gonna be riding at 350 watts, and Heather is gonna
be riding at 250 watts. (electronic music) – [Heather] Yeah I mean as
expected it feels pretty normal, I am used to riding deep section wheels and when it comes to a hill I’m happy to be out of
the saddle, in the saddle, and it’s gonna be interesting
to see how it compares to the disc wheel. – Okay, same thing again,
same hill, same power, but now I’m on the disc wheel. Let’s go. (electronic music) I actually feel alright when we’re on the shallower gradients but as it starts to pick up there’s a sort of fluctuation up this climb. I do feel it a bit more in those
slightly steeper gradients. I think it’s just that additional weight, perhaps when I’m getting
up out of my saddle, it’s just a little bit more material maybe just moving from side to side a bit more weight. Just feels a little bit
different, a little bit harder. Well that is the hill climb complete and that was quite hard work. – Yeah I’m glad that one’s over. – Yeah well on the deep section wheel , I was around 7:46 seconds – [Heather] I was around 8:50 on this one. – [Mark] And then on the disc wheel I was a fraction slower,
I was 7:55 seconds. – [Heather] I was also
slower on the disc with 8:56. – Yeah which I think has gone to show that we really should consider
our wheel choice options if you are doing a course
that is slightly hillier you’re going at gradients
that may be above six percent, you’re losing that aero dynamic advantage and you’re losing your speed. A shallower wheel, slightly less weight, maybe has a little bit more advantage. – Okay, what about the
speed that we’re travelling. This isn’t actually something
that I considered before but it’s partly the reason
that Enve have taken so long to release a disc wheel. – See, traditionally, a
lot of wheels are tested at around the 50 km/h mark, and obviously they prove that disc wheels are faster. But then how many of us
are actually travelling at 50 km/h during a race,
or at least for that long and particularly given
the length of a bike leg during a triatholon. So Enve have tried to be realistic in their approach to this in the past. That is why they’ve
tried to optimise wheels that are suited to the speeds that most of us are travelling at. According to their research, they’ve found that an open
spoke deep section wheel to be faster for the speeds that most of us are travelling at. But they have found that there
is the need for a disc wheel for some of those faster athletes and potentially on some
of those shorter courses. So if you are an athlete
that’s gonna be travelling at over 27 m/h or 43 km/h then a rear disc wheel may well be the better option for you,
depending on the course. – However, the wind is another factor that you need to consider. We’ve already mentioned the sail affect, so the deeper the wheel
the greater the sail affect and obviously the greatest when
it comes to the disc wheel. If you’ve got very strong cross winds, or even worse gusts, it can start to get a little bit harder to control your bike when you’ve got a disc wheel on the back. That’s actually the reason
that disc wheels are banned here at the Ironman World
Championships in Kona, because of those strong winds that come down off the mountain
and can really gust and catch riders out. It’s a worse effect the
lighter the rider is as well. It just makes your bike
that much harder to control, so you need to consider
this and think about the energy your gonna be wasting
trying to control your bike compared to aerial benefit
you’ll get from a disc wheel. – So in short, a disc
wheel is clearly fast if perhaps you’re planning
on racing a short distance, a flat course, or expecting
to hit high speeds. But if you’re not expecting to hit speeds in excess of 43 km/h, or for long, then a set of deep section
wheels may be the better and more versatile option for you. – As we’ve mentioned,
this wheel isn’t suitable for all courses. It is a big investment for performance, but if you’ve decided
that’s what you want to do, then for certain courses,
yes, there is that benefit. You’re probably gonna need to invest in a deep section wheel
as well for those courses when you can’t ride one of these. Well, hopefully you’ve enjoyed this and you want to get all
of our videos from GTN if so, just hit that globe to subscribe, and if you want to see our
seven aero hacks video, that’s just here. – If you’d like to see
our comfort vs aero video, where I play around with
different positions on the bike, then just click down here.

About the Author: Michael Flood


  1. Say whatever you want about wheels, ENVE are the fastest full stop. pro cyclists all want them if you ask them, but most cant say for sponsor contracts. in all wind tunnel tests they are best, on road they feel the best and online they cost the most!

  2. Without knowing what the hub internals are on the Disc rear, this may or may not be an accurate comparison and in response to the 43km/h threshold, Heather would have been travelling below that speed at 200W yet shaved time on the flat 5k which translates to a much greater time saved over a longer course. To anyone considering this as an upgrade I would say this: If you can manage a w/kg greater than 3 for the duration of a bike leg, and it's relatively flat, go for it.

  3. This is all so wrong. A disc wheel is faster, the more crosswinds there are and it doesnt give u lot of advantage if theres none. Crosswinds generate the sail effect. The same goes for deep section wheels but at lower yaw angles. Of course, they're harder to control. And a disc wheel's faster on almost every course, as the uphill parts always take less time then the flat and downhill sections (we're not talking about hill races…).

  4. In a race, you generally descend back which would probably cancel out any negative effect you get from going uphill. I'm not anywhere near the top of my age group but I find a disc to be faster on almost all courses. On the safety issue I feel a deep section front will cause you more problems than a disc.

  5. I'm sorry for getting into the habit of criticizing you guys, because I do like your channel.
    But riding so close to a car in order to film is not the best idea if you want to create data concerning drag.

  6. I ride all the time a disc wheel and I can't understand why people say it's difficult to control in crosswinds. A 80mm front wheel can be difficult to control. That is what I feel, never had a problem with my disc wheel, not even in ZA Port Elisabeth, it was the front wheel stopping me going faster or forced me to break…

  7. I ride both a disk and deep section wheels. I am lucky to be able to ride a disk wheel that is only 780g. I find for the same power over 56 miles I ride about 1-1.5 miles per hour faster then with just the deep section wheel. The only issue I have is in very strong cross winds, but even with that it’s more of an issue when I ride 80mm in the front.

    I’m a bigger rider so maybe that’s a major contributor to my situation.

  8. it dont matter so much the wheels, these videos are great but they all paid for by the brands punting their product, I have zipps and cheap alloy rims and honestly I still scratch my head over any amazing benefit besides looks. a fast rider will still be fast on anything

  9. I spent time as a race car mechanic in a previous life. It's job 1 to reduce any rotating weight first, then you go looking for static weight. The disk not only offers more static weight, but more importantly, it adds rotating weight. (Eating up double the power).

  10. when I was a kid in the '80s I had a Huffy Sigma BMXish bike that had "racing disc" wheels , i thought they were cool until I realized it was just plastic covering a regular wheel.

  11. I'm glad that sponsors are covering (at least some of) the costs of running this awesome channel for us. For the comments section, forgive me for mentioning the option to purchase a $100 aerojacket you can put on and take off your deep section rim, if compatible…

  12. Wow, Heather cut her time on the flat by 1.5% at ~38 km/h, whereas Mark, travelling about 43 km/h, reduced his time by 3%. Double the gain. I'm not at all surprised at the difference. But Heather's gain is significant, too – translates to about a minute in an Olympic tri on a similar course if you can hold 38 km/h. By the way, it was not a flat course if she needed 250 watts to achieve this speed. I ride a similar speed at 250 w on inferior equipment and obviously I'm quite a bit larger (larger bike frame, too).

  13. Oh come on guys … those glasses … are going cycling or skiing ?? Also, they aren't necessary when talking to camera. smh 🙁

  14. Shout out for custom made disc covers. I'm getting most of the disc wheel benefit for only 265g extra weight. Only cost me £11 to make too.

  15. Ok nobody can feel 200g up a hill. Empty your water bottle you’ll save more weight. You should have just used best bike split. Never mind enve’s junk numbers on disc wheels. Disc’s are always faster period. They provide more benefit for slower riders. And enve is the only company that says otherwise. Never mind the completely wrong fact about disc wheels being harder to use in crosswinds.

  16. Interesting that pretty much every other disc wheel manufacturer reckon 23 mph is the crossover point… and it’s not as if that disc looks any different to Zipp, Reynolds etc… they all weigh pretty much the same too! The advice is pretty solid though but consider the overall course terrain, 56 or 112 miles… you’re still likely to benefit overall unless it is Wales!

  17. Great Video. You find out that disc is faster in flat courses for 200 W and 300 W but then at the end you say that it is only faster when you ride over 43 km/h, but neither 200 or 300 w will get an average of 43 km/h. I am confused.

  18. Good video, but I have a question though: what was your speed on the flat at 200W and at 300W? Where you both faster than 43 km/h? Because at the end you say that it is only faster when you ride over 43 km/h of average so I'm confused about the 200W….

  19. Neglected one big variable, "placebo effect"..
    You guys may already expected the feeling and result before even starting the experiment, that can have a psycological effect..

  20. those glasses tho 😂😂😂. especially on the chick. women have a lot smaller faces than men do and she looks hilarious!

  21. So is it the rider or the equipment? Only track cycling is the answer since they use the same equipment. Road cycling is a mess right now with 6.8 kg bikes that is just embarrassing. If UCI would move bike weights to 10 kg riders would have to adjust their body training and get bigger. Road cycling is like watching horse racing with the midgets on top lol.

  22. Must be convenient to wear the same glasses in the water as on the bike. You forgot the snorkel though.

  23. Only had three rides with my deep section wheels (Zipp 808) maybe it’s just me, but I feel that when a gust of wind first hits the wheel, the wheels tend to get sucked into wind rather than being pushed with the wind. I’m no way near being a fast rider but my average speed has increased by 0.5mph since fitting the deep section wheels.

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