RPK79

wjclint

I know this wasn't directed at me, and mine are different, but here some information on a 4,000 mile, little over a year, 170 lb rider, North Texas weather, brakepads that came with the wheels, and another set of black prince brake pads, speed of uhhh (wait, speed?) on "Chinese" carbon clinchers (since apparently all rims manufactured in China are exactly the same since they are all assessed as a group based upon every forum thread title ever, and plus they all look alike).

https://www.bikeforums.net/road-cycli...l#post16974208

WhyFi

That's racist- not all of the Chinese look alike.

surgeonstone

But he is always right.

surgeonstone

Easy big guy, it's bad form to refuse a peace offering.

Campagnono

Two things.

1) Regarding the Wong Fu Deng Ultra Light wheel set in question, which would be my 74th choice if I had to give my wheel rankings, I feel BDop is just giving accurate advice and defending his own turf on the relatively superior Novatec JCM10-1234876-45446AN-645R1909M wheel set which would easily rate as my 65th or 66th selection.

2) It is boss that the OP stuck Tufos on those bad boys.

RollCNY

I don't think he implied it.

Bob Dopolina 

A quick note. We don't actually sell the Novatec wheels. There are distributors in most markets so we can't sell there plus the shipping from Taiwan is killer.

We post the specs and links to local sources.

Yeah, defending turf is partially true but it's more like getting really sick of the flood of cheap Chinese crap into the market. The good vendors in China work in the OE or are owned, at least in part, by the brand. Different animal.

We are even starting to see fake Novatec hubs now. It's just ridiculous. There are just too many players in China who lack any sense of business ethics. We made the conscious choice to not do any business there whatsoever because of the constant problems we saw and after testing dozens of products and working with other vendors here who had done the same types of testing.

You can get lucky with Chinese carbon and they are fine or they could asplode. It's really a crapshoot. All of the foam core rims form China we tested failed.

Bob Dopolina 

Dam skippy!

surgeonstone

That'll be a pair of free, non cheapo, non alibabby carbon wheels.

surgeonstone

Out of curiosity, how many foam cores did you test.

Makel

FasterNearGirls

Subscribed

bt

questionable wheels is not an area I want to explore.

Thank goodness for test dummies.

Bob Dopolina 

...and that would be a reference to whom exactly?

Bob Dopolina 

We tested rims from two vendors.

We have an OE customer who also tested a rim from one of the same vendors.

We work with an assembly factory that tested some (I don't know how many) and shared their results with us.

A carbon marker in Taiwan we work with has also tested some of these rims (again, I don't know how many) and shared their views with us. We were developing new products and discussing various methods we could use and they flat out panned this one.

A lot of information we get is shared from vendors we work with. Once there is a level of trust it saves everyone a lot of time and energy.

Campagnono

I really can't believe consumers knowingly buy the Chinese products, whether they are no-names or explicit knock-offs. And this transcends the bike market and every product class is abused and cheapened through Chinese production. There is a reason money is saved with Chinese purchases, and this is because their producers have a sincere and purposeful lack of decency in wages, training, quality, environmental ethics, regulatory ethics, and this is combined with a mercenary and criminal interest in fakery and illusion and an unfortunately exceptional technological capacity in the ability to do so.

I only buy products made in the EU or the USA. If we continue to selectively support China then our own alternatives will be gone one day.

I was just razzing you with the Novatec slight. They are decent rims for a price point that many customers need. I'm glad that your skin is far thicker than Ultegra Chinese Fanboy.

I am in the industrial chemical recycling and disposal industry, and can without a doubt or any speculation say that we are in a tragic new era of ethics involving China. We are now at the point where great nations like France, England, and the United States make the decision to (legally) ship MILLIONS of metric tons of chemical waste to China to simply have it dumped into sand pits or directly into rivers because this offers a cheaper rate then reacting the waste with additional chemical inputs, holding them in on-site storage, finding other local (higher priced) disposal contracts, and securing the required EU or EPA permits.

This is our planet, we all share this filth. And we need to stop being complicit in sinking our own ship. It is a tiny, tiny world. Just because many of you cannot see it, China IS your backyard.

Sorry for the rant. China is no good for anyone. Even if they were the best carbon wheels in the world, the externalities involved are horrific.

coachboyd

OK, this will be long. But I have had a lot of experience with foam core rims as we had thought it could have been a cool option if it worked.

I was tempted by the foam core rim promises a couple years ago. They seemed super light weight and the thinking behind the engineering seems solid. With the foam acting as a structural core, the wall thickness of the rims can be a lot thinner. The carbon doesn't have to support the compression of the rim, it's only surrounding and holding the foam in place. If you cut open a foam core rim (which I did) you'll be amazed at just how thin the walls of the rims are.

This was right around the same time that we were developing our new molds and I had thought "How cool would it be if we could offer a 1000 gram set?" So I contacted a few companies that were selling the rims and ordered a few sets of rims from each one. All three companies told me I could do my own mold with them. I knew they weren't the actual manufacturer, but would act as a trading company.

So, the rims arrived. I got a mixture of 20mm, 32mm, and 50mm rims. These were only for internal use and testing so see if going the foam core route would be a valid one.

The first rims I built up were 20mm tubulars. I used alloy nipples and fairly lightweight hubs. We had to use nipple washers under strict instructions from all 3 companies. They laced up to 928 grams for the set.


Noticed I said laced and not built. The walls were so thin that we only got 2 of the front wheels and no rears built without the wheel cracking under tension. One particularly scary instance happened when one of the spokes started twisting in the front wheel when we were building it. When this happens we usually just cut out the spoke and put in another one. The wheel was at tension and when we cut out the spoke, the wheel folded in half. I have seen reports of this happening on weight weenies. The rim is so light and so thin that the force of two spokes in a row pulling towards the same side was enough to taco the wheel. So if you were ever riding and broke a spoke, it could be catastrophic.
Needless to say, the 20mm option was out. I certainly wasn't going to risk the liability of trying to have a wheel that thin and light.

The next ones we tried were the 32mm. These were the ones that I was very interested in as the drawing we had for a new rim was about 30mm deep. This was a lot better as all three sets built up without cracking. We were able to mount and glue tires on all three and even use them in some races (my teammates are sometimes guinea pigs). We had a hilly race and I let my very small teammate use them, he was weighing in around 135 pounds (but eats more than anybody I know). After the race, his feedback was that they accelerated nicely and were definitely light but it was the flexiest wheelset he had ever ridden in his life. A bunch more rides over the next month verified this.
Over time almost all the drive side spokes started developing cracks, even from the tension of just sitting there. I went into the office one day and found that a spoke had almost completely puled through the rim just from the tension of being laced up. I took a set on a hilly ride where I had to ride the brakes for a while and this is where the scary part happened. The foam core was acting as an oven. It would hold the heat when braking and transfer it to the side of the rim. After a long ride the walls became very wavy from the heat of the foam core. If the walls had been a little thicker they would have been more structurally sound and probably would not have deformed. But then, with thicker walls the need for the foam core is not there which is why it's not used on most carbon rims.

We did not build up any of the 50mm and eventually just threw them away. OK, we actually threw them against a concrete wall in our basement first :-) We have done this with a lot of carbon rims, like if something gets damaged in a crash. It's actually pretty fun and you start to realize just how hard carbon can slam into a wall with no damage happening. We've done it with alloy wheels as well. With most carbon wheels I would have no problems riding the rim after throwing it against the wall as hard as I can. However with an alloy wheel the hook will bend a bit upon impact which would cause a lot of pulsating when braking. The foam core after a couple of times against the wall had cracked all the way through. Now, that is the most unscientific (but one of the most fun tests) that we can possibly ever perform. . .but I bet I could charge money to let people perform it, haha.

I knew foam was not going to be an option for us, especially with the problems with the braking causing the walls to deform.

I will say the one really nice thing about having a foam core was lacing up the wheels. Since the foam was drilled down from the rim bed to the spoke hole, we could just drop a nipple down in the rim by hand. We didn't have to worry about losing any nipples inside the hollow rim. That was about the only positive experience I had with the rims though.

kingfishr

+1 Nice to know there are two of us now

Bob Dopolina 

@coachboyd. This lines up with our experiences and those that we have been told by others we work with. There may be vendors doing a better job with this method but I believe it is fundamentally flawed and that there are better ways to build a rim.

canam73

I don't ultra lightweight stuff or road disc brakes, but am I wrong in thinking that provided they made the spoke bed strong enough a foam core rim could be a good match for making a lightweight road disc wheelset?

sced

and also the side walls...sounds like the designs were just bad as much as anything.

canam73

Sure, my point is wondering whether it could be a viable option if executed properly.

BikeWise1

1000 gram wheels? Do Not Want. But I suppose they are perfect for record attempts and club rides and the attendant bragging that goes on at each. Not much else.

sced

When 1100 gram wheels won't do.