I appreciate your response as you are using wheels in a strategic fashion... What brands of aero wheels do you ride? Also the Bastongnes use a wider rim and although not "aero", they are supposed to be more aero assuming one uses a 23mm tire. But this wouldn't make them spin up fast... what do you account for their superiority? What other alloy clincher have you used in the past? Have you been tempted to upgrade to the Ardenes?

Tyres, type and size..Pick size for what speed and use (yeah tyres, I'm euro)
Tubes, latex can save U some (20W :eek: Right lol)
Pressure
aero spokes
aero rim
bearings, thou that's kinda over emphasized
your fork (WHAT? :eek: yeah...Turbulence from wheel)
balance
weight distribution front/rear

Those are the main factors.

New riders are today's lurkers and tomorrow's contributors.

umd has a graph for this.;)

lust bike who told you that the ES wheels are fast? Some mavic stuff is pretty bad if you ask me. Even old shimano 105 sc hubs go faster than some mavic hubs. Just my experience. In my opinion some mavic wheels are just something to keep people interested because the REALLY good stuff is just too expensive for normal human beings. So sometimes get something so so in price is better because u really get your money's worth.

I don't know if this was meant for me but since I mention the Bastogne...

Aero wheels I ride now: HED (Stinger6 for racing, Jet6 front and Jet9 rear for training and some races)
Sometimes Specialized Trispoke (now HED3), aluminum rim version (the only version Specialized made).

Aero wheels I rode: DV46 clincher (sold to teammate), DV46 tubular (lent to teammate), Zipp 440, Zipp 340, Campy Vento (16 spoke version, I don't consider the G3 version aero), proto disk wheel rear, HED disk wheel rear, Mavic Cosmic Carbons (first gen), Spinergy RevX.

Alloy clinchers (non-aero) I rode (not comprehensive): Mavic G40, Open4CD, FiR EA60 EL45 Zenith, Sun Mistral err I forget the model names but box section and "aero", Campy Vento (G3) Eurus (steel spoke), Spinergy XAero, whatever SPinergy's non-aero XAero was.

Non-aero tubulars I rode: Mavic Heliums GP4 SSC, FiR Isidis Alkor some others, Ambrosio stuff, Campy Record Crono and others.

The Bastognes may be aero but I can't tell. I wanted a low spoke count wide rim for training. The Bastognes were the cheapest low spoke count wheelset from HED - the ones below it all have more spokes. I didn't consider the Ardennes at all. Nor did I consider the Flamme Rouge upgrade (a hub lightening thing) for any of my wheels. I bought all the current HED wheels in 2010 so I had a choice on what wheel to buy or not buy. I don't regret buying the Bastognes. I regret buying the Jet9. I would have bought a Stinger9 rear instead.

Spin up is a function of inertia - since hubs affect inertia very little, it has to do with rim and tire weight. At higher speeds it also has to do with spoke count. Aero wheels don't necessarily spin up faster - they just keep accelerating.

An FYI - one cannot tell how good bearings are by spinning a wheel while holding it in one's hands. That measures, among other things, bearing seal drag. Spinergy had excellent bearings when they started, but when Mavic came out with wheels that had poor bearing seals (and therefore "spun better"), Spinergy had to react. Against the wishes of their engineers they eliminated the bearing seals. Suddenly Spinergys were "fast".

A similar myth surrounds derailleur pulleys. If you get a cartridge bearing pulley and spin it with no load, it'll probably spin slowly. A bushing pulley should spin pretty well. A loose bearing pulley spins pretty well too, the nicest really (Campy). But put a load on it (i.e. chain under tension) and suddenly that cartridge bearing pulley works really, really well. Put 1000 miles on the drivetrain and that cartridge bearing pulley will now pull ahead of all of them. Even the loose bearing Campy pulley slows down when it's dirty.

So a "spin test" is not a test of mechanical advantage. It's a test of how the wheel feels when you spin it in your hand. Nothing more.

A properly adjusted round bearing surface hub is pretty equal to other properly adjusted round bearing surface hub. I include "round bearing surface" because the 105 loose bearing hubs (and lower) all had oval bearing races and could not be adjusted. Only the machined bearing surface hubs (Ultegra, Dura Ace) were smooth consistently. Since bearings make so little difference, I basically ignore them. If a bearing goes south I'll just replace it (since I have pretty much all cartridge bearings in hubs/BB).

Hub shells, other than weight and strength, also make no difference. I want a wide flange for lateral rigidity. The Mavic hub of yesteryear, while beautiful, made for a super flexy wheel. I imagine the same will hold true of narrow flanged hubs by anyone.

I'll post now edit later.

cdr

I wonder why the wheels on my lowracer recumbent are so much faster than the wheels on all the roadies on diamond frames?

and

These are two excellent portions of advice and pretty much sums up this thread.

I find it pretty funny that so many people think that it's always about training and the placebo affect...all the time.
Of course if you train more you will get stronger, duh. Changing a pair of wheels from one day the the next and doing the same ride and feeling a difference is not training...it's an equipment change. get back on your 25lb steel bike and ride a race instead of your 15lb carbon bike and see how you feel...
I race on two pairs of wheels and like CDR above, I can feel a difference in certain races. In one of the local mid-week crits, I have been back and forth on Zipp 404's (aero) and Easton EA90 SLX (light). The ea90's are faster to spin up, which is good because it's a tight course with lots of surges and attacks. The 404's are good because they stay rolling fast more easily. If I'm near the front or off the front, then the 404's are better because you don;t get the slingshot affect of the pack. If i'm in the pack, the EA90's are better for matching the acceleration.
Climbing races I use the EA90's cause they are lighter and I'm not as strong on the climbs as I am on the flats.

Wheels makes a difference for sure. Should an out of shape recreational rider buy $3000 wheels to be faster? If they can afford it and they want to, sure, why not. Could they gain the same speed by training harder and putting on more miles? Yep.
P.S. why is UMD mentioned in every thread, all the time?

fat people go downhill faster.

/\ lol!!!

Thank you. I couldn't think of anything to say.

The point is that even the most zealous marketing out there only claims a 10-20W advantage for high zoot wheels, and that's at 30+ mph. As CDR points out, that can buy you 20 ft in a sprint, but that's not the reason that someone at this guy's club ride suddenly starting being faster than him.

No way that's placebo, right?

Spin-up is completely bogus. Put your bike in a stand and give the crank a solid push with your hand. You can easily get the rear wheel up to 20+ mph (use a computer with a rear wheel sensor). That's how much energy it takes to spin up a wheel due to its inertia: the amount you can deliver in a quarter of a crank turn with one hand. That might be measurable in very controlled conditions, but no way you're going to feel that difference on the bike.

Yes, they can make a real difference, but not nearly to the extent that a lot people seem to think.

I'd contest this remark. Placebos and all that, fine. But if you get a nice light wheelset (say sub-1400g, and if you're fortunate to have some, sub-1100g, and both of them tubulars) and a "regular" wheelset (1800?g), it's going to be hard to say that both wheels spin up at about the same effort.

In fact, if you get a chance to try two sets of wheels, you'll be astounded at how fast your bike accelerates. You literally need to adjust your riding style to accommodate the much shorter acceleration time.

Fine, it's 1 or 2 lbs but that's what it is between my tubulars and some of the clinchers I have - and it's all in the rim/tire area since the hubs are identical and the spokes are close if not the same (technically the clincher spokes are longer because of the non-structural fairing, but I doubt I'd be able to tell the difference between the spoke weights... and the spoke counts are same/similar).

Spin up, btw, is much different than weight overall. Light wheels don't help me climb better. I still go really slow once I get into my FTP mode (i.e. blown up). The difference with lighter wheels is that I can accelerate harder, especially when I'm more fresh.

Wheels don't make the difference between riding "levels", but between riders of the same level, wheels can make a significant delta in performance (acceleration and rolling/top speed). So giving an aero wheelset to a 23.5 mph time trialer is not going to make them a 28 mph time trialer. I know because I'm that 23.5 mph time trialer. If you give normal wheels to a 29 mph time trialer, that person still beats the 23.5 time trialer.

I've won sprints on aero tubulars (light + aero), box section wheels (usually light), but never on heavy aero wheels.

cdr

I do something similar when I switch from winter wheels/tires to summer. There's about a 700g difference between the two. No difference so noticeable I need to adjust my riding style.

Again, do the test with a bike in a stand. You can spin up a bicycle wheel to well over 20 mph (literally) one-handed. It's not something that's going to make a difference.

So, if I reading this right lighter wheels equate to no gains at all correct?? That seems to be the view some are taking.

I think there is such a hard delineation between those who think it has negligible effect and those who think it has a noticeable effect it's making it difficult to actually make any leeway in terms of conversational progress. Add to that a bitter history of the two camps and you have little middle ground. It probably doesn't help that there is little definitive evidence to support either side.

It's not really a question if variables such as hub friction and wheel set weight affect spin up speed, acceleration, and velocity. Physics 101 teaches that. It's just a matter of how much of an effect these factors have on a ride.

The only thing that your test proves is that it's pretty easy to spin an unweighted wheel that has virtually zero load on it. Throw your car on a chassis lift and manually spin one of the non-drive wheels- we'll wait for you....

All done? Pretty darn easy huh? That must mean that you can propel a 3000 lb. object with the 3 watts of power that you generated with your (presumably) dominant arm, yes?

No. It all changes once the wheels hit the pavement. Have you ever seen slow-motion footage of a drag race (funny car, dragster, etc.) tire? Believe it or not, the same forces are at work in a bicycle's rear wheel- albeit on a much smaller scale.

http://bikeforums.net/attachment.php...hmentid=183806

Depending on the intended purpose, higher-end (let's call them stiff) wheelsets, essentially, deflect less when torqued under load. They're better at resisting the "twist" that always (yes always, however small) occurs when rotational forces are applied. If the wheel is stiff and aerodynamic, they also move through the air more easily due to a lower coefficient of drag (owing to their high profile, etc.) Many often note an "easy spin-up" with climbing wheels. In my limited experience with this type of wheel, it seems that the sheer lightness of the wheel would be the main contributing factor here. In either case, the goal of higher-end products if to minimize the amount of wasted energy.


Spin-up is a real phenomenon that can be measured and quantified. Whether or not you can produce enough power to objectively note a difference between wheelsets is a personal issue that is best addressed with more training.

When speaking of a wheel's stiffness, I generally am more concerned with lateral stiffness

I don't exactly know what a chassis lift is, so I don't understand the point you're trying to make. If you're saying the car is lifted up with the wheels off the ground, then yes I can spin them easily. And yes, that has nothing to do with propelling the car while it's on the ground because, well, it weighs 3000 lbs. This the same point: spinning up a 1000 g wheel takes very little energy compared to the energy required to accelerate a 100 kg rider+bike system.

Put another way, I can't spin weighted car wheels because I have to also (translationally) accelerate the weight of the car. In principle, if the car were on very slick ice, then I could still spin the wheels.

None of this has anything to do with the inertia of a wheel, which is what most people talk about when they are talking about spin up. e.g., "These wheels are so light, especially at the rim where it counts, so they're so easy to get to speed." That can also be measured and quantified, and it's really, really small.

It's also a little dubious to compare a 1000 hp engine to a 1 hp cyclist, but I'll admit the stiffness question is more complex.

The point I was trying to make was that people don't "measure" spin-up with the wheel in the air and their hand spinning the crank. You say that the idea of spin-up is bogus and that you believe this to be true on the strength of your prescribed test.

I'm saying that your test is invalid to quantify spin-up because your test essentially only looks at rotational mass- when there are lots of other variables to consider. If spinning a wheel on a stand means "spin-up" to you, then OK, you're right, there's almost no perceptible difference between any bicycle wheel. However- "I do not think it means what you think it means."

I don't believe that easy spin-up should automatically be equated with sheer lightness- which is what a lot of people seem to do when trying out new wheels. I think of spin-up as a function of actual riding, with real loads and forces acting on the wheel. As such, I see the concept of spin-up as being more related to the stiffness of a wheel- and this appears to be where you and I differ.

I'm no physics expert but lets clarify a few things...that may be entirely inaccurate because i'm not a physics expert.

The discussion of "spin-up" is all about rotational mass.

Low rotational mass allows them to spin-up faster. The problem with this argument (spinning a wheel on a stand) is that all the forces that magnify the effects of higher rotational mass are...next to nothing. Thus, the benefits of a low rotational mass will be...next to nothing.

It might be different in drag racing, but most of the time people here talk about how easy wheels are to spin up because they're light. Do a search, or even look at the posts in this thread, or at a Bicycling magazine "review."

But, yes we agree on the physics at least. I still think stiffness of a wheel are way overrated, but you're right in that an unweighted spin-up doesn't tell you anything about that.

The consensus of the most experiened and knowledgable people that post here is lighter wheels makes a difference in quick accelerations and with climbing