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Road Bike Wheels For Sale | Carbon Wheelsets - New & Used | TPC – The Pro's Closet (theproscloset.com)

Duragrouch

See post #11 and #16.

VegasJen

Since I'm OK with some of these products out of Asia (budget restricted), I'm looking on Amazon. Any first hand opinions on Superteam, Ican or EliteWheels?

Duragrouch

You're correct to ask here, though I don't know. But I've found that reviews on amazon can be very helpful, especially if the product has been around a while.

VegasJen

I'm skeptical of some Amazon reviews. I was just looking at a stand-alone GPS unit for work and 5 out of the 9 reviews just felt like sponsored reviews. Poor English, not even correctly identifying the product being reviewed, etc. Obviously, some legit reviews but can be difficult to weed out the good from the fake.

Duragrouch

Yeah, exactly. 9 Reviews is a very new product. That's why I said that a product that has been around a while, hundreds of reviews, is a better bet. Some will say just good or bad, but the gems are the reviews with specifics.

base2 

I read post 11 & 16. Basically we are in agreement & I linked to one such purchasable example with reasonable width, tubeless capability and decent rim brake performance for carbon.

VegasJen

I checked them out. It's a consideration but if it's coming from Asia, there are other competing products out there to consider as well. Right now looking at a set of 38mm deep Elite wheels. The price is right for a set.

DangerousDanR

I have ICAN wheels on my fat bike. Several years old and I have beat on them pretty hard. Still true and never had to tighten the spokes.

VegasJen

Thanks for the review. That is a brand I am considering. I would still prefer wheels produced outside of China if at all possible but it can be kind of difficult to determine the actual location of manufacturing sometimes. I'm sure that's intentional.

DangerousDanR

I also have a set of Roval (Specialized) Terra CL carbon wheels on my gravel/touring bike and I believe they are made in Taiwan.

Duragrouch

I just looked at your profile, so you may be interested in this. A good book on sailing yacht design, Principles of Yacht Design by Larsson and Eliasson (I read first edition twenty years ago), has a section on rudder design, aiming to avoid vibration via flow separation; IIRC, recommends trailing edge with no more than 20 degrees taper per side, and if needed to be more blunt for durability, not fully rounded, but rather, a very crisp truncated trailing edge with sharp corners. My boat has the latter. Someone sails my boat, likes it, there's a new dealer in the PNW that started carrying it, first on the west coast. Dealer shows up with the demo boat, we take for a test sail, *massive* vibration from rudder transmitted to tiller. I look at rudder, thick, fully rounded trailing edge. I email boat maker indicating exact page in above book to reference, they apologize for quality lapse by rudder maker, ships out a new rudder blade.

VegasJen

This carries through to automotive design as well. If you notice particularly the last generation of Corvette, there is a very sharp angle completely surrounding the rear bumper cover. While there are all kinds of shapes and things going on within that border, the idea is to break the air cleanly.

So what I'm thinking of doing with my 80mm Reynolds wheels is getting some "grip tape" and cutting very thin sections to make a textured surface. I'm thinking about 1mm in width and just a little larger than the inside diameter of the wheel. The idea is just to break up the surface tension of the airflow over the carbon fiber. Will it work? No idea, but my Ridley Cheetah originally came with something very similar over certain parts of the frame. At $9 a roll, it's a pretty inexpensive experiment.

Duragrouch

You are correct about the Corvette, I think you mean the C7, the last front-engine one. Good observation.

It may work, it may do the opposite. On many sport coupes these days, particularly it seems hot Subarus, you will see on the back end of the roof just in front of the rear glass, small fins, vortex generators, to introduce energy into the air stream and delay flow separation, to pull the air down along the glass to reduce the size of the wake turbulence which forms a low pressure zone pulling aft on the car. You will also see these on some commercial aircraft wings to delay stalling at high angles of attack. The dimples on golf balls do the same thing. These are known as "energy adders" (a chapter in Flight Theory and Aerodynamics by Dole). A few years back, I recall that one of the aero bike wheel companies had put dimples on the rims to do the same. So adding textured tape could break up the laminar flow and kill the lift, or it could energize the air stream to do the exact opposite. (The example you cited of tape on the frame, may have been just like the golf balls, to delay flow separation around vertical frame tubes for lower drag.) I vaguely recall an article, decades ago, about putting small chevrons on surfaces, a regular pattern did one thing and a random pattern did a different thing, sorry I can't remember details, been too long. Experimenting is cheap and easy, go for it. Ideally you'll have some way of measuring things, if not by quantity, a qualitative way, such as using a fan or blower side of a vacuum cleaner or leaf blower, to blow air across the rim at various angles to simulate it moving forward in a crosswind, and some form of smoke like a blown-out match, held just forward of the rim, for flow visualization. You can also tape on fine threads ("tufts") to see flow. Sails often have these on both sides to aid sail trimming, angle with respect to the wind, ideally having both streaming aft along the sail on both sides. These are known as "telltales", one of many sailing terms that has entered the vernacular. Old audio cassette tape (thin mylar) makes excellent telltales, at least on sails.

Or, just ride the bike in a crosswind and see if it feels better.

Aeronautical and aerospace engineer Burt Rutan, in his early days testing his VariEze design, propped it up on a flatbed trailer at various angles and towed it down a runway, making visual and instrumented observations. A poor man's wind-tunnel.

base2 

Duragrouch That does seem like an interesting book. The dynamics of water and air have obviously different optimizations but the principals are the same. I'll check my local library. Thanks!

terrymorse 

FWIW, the “tripping” of the airflow intends to change the laminar flow to turbulent, which doesn’t suffer the same air flow disconnection as laminar aft of the body. Tripping airflow was one of the lab experiments we were punished with in fluids class, a long time ago.

asgelle

The thing with trip strips is they have to be positioned precisely so the flow remains attached to the surface longer. If you don't know what you're doing and don't position them correctly, you're likely to increase drag rather than decrease it.

But are you able to carry out the experiment with enough precision to see if the tape is helping or hurting?

Duragrouch

When I read it (first edition), they went through a complete case study of designing a 40' performance-cruising sailboat (IIRC), every aspect. Very technical. More enjoyable reading was Yacht Design According to Perry by Bob Perry, a famous designer native to north of Seattle; That book was not technical, but covered many of his designs, and he was honest about what he still thought was good, and what things were simply fashionable in design at the time but he would do different now. A particularly amusing story he has posted online, The Lafitte Story, about the origins of the Lafitte 44, you should be able to find it with a quick search.

VegasJen

Carry out an experiment? Nope. All I'm looking to do is see if I feel a little more stable in a cross wind. If I do, then I will consider it a success. If I don't, I'll pull it off and try something different. Like I said, it's a $9 experiment.

asgelle

Yes, that's part of it, but if the wheel is more stable with the tape, don't you want to know it isn't slower now than the shallower rims were?

VegasJen

I think I may have found a wheel set that ticks all the boxes I'm looking for. Anybody have any experience with Intrepid? The 35mm is probably about as shallow as I want to go but it should do much better in cross winds than my 80mm wheel does.

https://www.kurecycles.com/products/...epth-rim-brake

They're a few hundred dollars more than what I hoped to spend, but I'm one of those people who really does put her money where her mouth is. Main reason is I really don't want to buy Chinese if there is an option. Budget is a factor in that option. I'm willing to spend $800 over $400 if it means not buying Chinese. I can't spend $2000 on a set of wheels. That's not a budget buster, that's more like a pocket book hand grenade.

Anyway, this is about the only wheel set I've found that actively advertises not being made in China.

tFUnK

Never heard about them but this looks good on paper.

Duragrouch

First, it would be good if you can find product reviews somewhere and see how long the company has been producing carbon wheelsets.

Second, the freehub is touted as 150 ratchet teeth, and that's pretty fine tooth. It would be good to know the durability record of that, and, what type of interface at the hub in case you want to replace with a more common freehub, that's good to know for the long term in any case, as freehubs do wear.

I assume that ratchet freewheeling noise is not a factor for you because you'll be pedaling more than coasting. I've just heard some bikes in recent years with carbon rims, don't know if that is why, but either the ratchet is noisy period, or the wheel style somehow amplifies the noise.

VegasJen

Interesting you say that. I have been looking for some reviews and there is precious little info out there on these wheels. However, I did find this video on teh Youtube. Only review I can find and who knows how legit it is. But if it is legit, they sound like a pretty good option.

VegasJen

Follow up review. Only two reviews I can find.