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Old November 30th 18, 09:17 PM posted to rec.bicycles.tech
JBeattie
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Default Danger from CF rims

On Friday, November 30, 2018 at 10:07:27 AM UTC-8, wrote:
On Friday, November 30, 2018 at 9:33:15 AM UTC-8, jbeattie wrote:
On Friday, November 30, 2018 at 7:28:14 AM UTC-8, wrote:
On Thursday, November 29, 2018 at 5:24:01 PM UTC-8, jbeattie wrote:
On Thursday, November 29, 2018 at 3:05:02 PM UTC-8, wrote:
I previously bought a set of 50 mm deep Carbon Fiber rims. These were clinchers and were 23 mm wide on the brake surfaces. These have performed faultlessly.

But I didn't want to have to carry around all of the 2 lbs of flat repair stuff - the Topeak bag, multitool, two spare tubes, two CO2 cartridges and the tool to use them and a patch kit ifneeded.

So I decided to go to tubeless as I have successfully used on Campy and Fulcrum aluminum wheelsets. They were selling the 25 mm wide tubeless wheelsets nearly as cheaply as the clincher rims.

I bought a set and they arrived. I also wanted to try 28 mm tires on my Colnago so I was mounting a set of Michelin Pro4 Endurance tires like I had used on my Pinarello Stelvio. The front appeared to mount and hold air as normal for a new mount. Usually it takes a couple of days for all of the small leaks around the sidewalls to seal. You just pump it up until it hold air pretty well and then go for a ride and that jiggles everything into place and you don't have to worry about flats again.

When I was inflating the rear tire and inflating it, there was a loud POP! and I put the wheel into the wheelstand and it was an inch out of true. I assumed this was from delamination but as the wheel was spinning in the stand the air was draining out of it and it came back into true. I pulled the tire off and looked carefully at the entire rim but couldn't see anything. I contacted the seller on Ebay and they sent me a rim which I've covered elsewhere.

In any case I ordered a second wheelset from another manufacturer.. They came in pretty fast so they must have gotten to the boat just as it was leaving.

I discovered with the apparently good front wheel that there's insufficient room on the CLX 3.0 to use 28 mm tires. Conveniently Vittoria just released the Corsa Speed tubeless tires so I ordered a set from ProBikeKit. It took a month to get here so it was just a couple of days ago I tried putting them on. I had a lot of problems getting them to push up onto the step that all tubeless rims have. In fact I used up 5 CO2 cartridges without getting one properly mounted. So I had to order another lifetime supply. I expected them to arrive in another week but they were here this morning!

I mounted the new tires and inflated them and they didn't fill properly still. They were spraying the sealant all over the place. Finally they seemed to mount properly. The air pressure was low from all of the leakage getting them on properly. so I stuck a pump on and started pumping them up at around 65 psi they started TICing and when I got to 80 PSI they exploded loudly and the way the tire felt I thought that it had broken the bead. I tried the other wheel and it did the same thing. When the pressure got to 70 psi or so it began making funny noises and at 80 psi BANG!

I called Vittoria America up and gave them a piece of my mind and they were the nicest people in the world and just gave me a return ID and said that they would replace them.

So I went through the process of taking them off with all of that sealant inside. I got them off and there didn't seem to be anything wrong with the tires. So I rubbed by fingers along the top of the rims and one was delaminated for about 10 inches while the other was delaminated a third of the way around the one side of the rim. I kept the wheel box but I cannot return them through Ebay until I communicate with the seller.

Now the tube bed on the clincher wheels is completely different than that of the tubeless so I don't expect any trouble with them. But what is important to note is that probably all 50 mm deep carbon rims are made by the same manufacturer. This makes them all suspect no matter whose decal is on the rims.

If you want the advantages of a good aero section that you can get from carbon 50 mm wheels you should think more about a clincher set. These have more re-enforcement around the brake area.

WTF? You and cheap carbon wheels should not be on the same planet together. Go get some decent aluminum rims and call it good -- or some CF/aluminum hybrids like the DuraAce. They're a good value and getting cheaper because of the shift to disc wheels. You can skip the special brake pads and sketchy wet-weather braking -- or in your case, hot weather braking on long descents. For most people, CF rims are a solution in search of a problem.

-- Jay Beattie.

Just out of curiosity - how many miles do you put in a year? How much climbing? What sort of bikes do you ride? Since you don't seem to be aware that DuraAce doesn't offer Campy freehubs I have to question what sort of riding you do.


I don't keep track of your equipment choices. Sorry.

To answer your question, I ride 5-10,000 miles a year, depending on the year -- probably 7,000-ish average. Maybe 5-10K climbing a week, which will ratchet back during ski season. Purely commute climbing is about 2K a week because I have to climb a minimum of 400 feet to get home every night, and I can go home directly over the West Hills for 1,100 feet of climbing in a short distance. Doing 5K of climbing on a single ride is not a big deal during the summer. We have a lot of hills -- but alas, no major climbs like Mt. Hamilton until you get well out of town. The Santa Clara Valley was better for long climbs close in. You have to string short 2-4 mile climbs together around town. For longer climbs, you have to head to the Mt. Hood territory. Great gravel riding. https://ridewithgps.com/photos/961734/large.jpg

Bikes are Emonda SLR9 (pro deal from client Trek -- thank you Trek, awesome bike), Cannondale Synapse (fast rain bike -- insurance replacement for stolen Roubaix), Norco Search 105 CF gravel bike ($1,500! -- incredible deal at Western Bikeworks) and a Cannondale CAADX commuter (warranty replacement frame), with a leaking BR-RS785 front disc caliper, which is a whole other story. I also have a 1970 Raleigh Pro track bike from my track racing era -- now for riding rollers in the basement. This collection does not include my son's bikes. The garage looks like a bike shop.

My only expensive wheels are some Dura Ace C35s and the HED Ardennes discs on the Synapse. I also have some OE wheels and wheels I built on a variety of aluminum rims. I have no pure CF wheels and don't anticipate getting any. I would never buy a FleaBay Chinese CF wheel.

There is a reason that most of the Pro teams use Campy. Though often I wonder why since my one Ultegra bike seems to work very well except the shifters are extremely sensitive to getting dust in the mechanism after which they are throw-away.


There is a reason that most pro teams use Shimano. https://bikerumor.com/2017/07/25/shi...our-de-france/

I rode the same 9sp 105 levers on my commuter for 15 years -- in rain, snow, mud, etc., etc. My son had an Ultegra left/rear shifter seize up. That's the only STI fatality since 1992, IIRC.

-- Jay Beattie.


OK, you ride a good deal. You have good equipment. Then why aren't you aware that most of the wheels built today are in China? Hell, Except for 105, Ultegra and DuraAce groups everything Shimano makes is made in mainland China.


From what I can tell, you bought knock-off Chinese wheels of unknown pedigree on eBay. It's like buying a Chinarello or some open-mold grab bag bike frame made after-hours from floor scraps. Maybe you luck out and maybe you don't.

If you buy Shimano, Trek, Specialized, etc., you are also getting their QC and oversight. Shimano over-lords are watching every move of those inscrutable Chinese factory workers! Welcome to Nanjing 2.0! Actually, though, they ensure that the factories are ISO certified and are producing quality products. And, BTW:

"Approximately 90% of Mavic aluminum rims are produced [in France], with the other 10% being made in Asia,’ said Mavic’s Michel Lethenet. ‘And this 10% is made up mostly of Mavic’s more entry-level wheels not suited for high-performance road cycling and mountain biking; those are made here in St. Trevier.’ Mavic’s carbon rims are designed and prototyped at the company’s headquarters in Annecy, France, while mass-production of the carbon rims is carried out in a factory in Romania."

https://roadbikeaction.com/being-the...s-rim-factory/

Also, way more pro teams use Shimano.

"Of the 18 WorldTour teams, 14 use Shimano drivetrain components either fully or partly and a 15th team in Katusha-Alpecin use Shimano direct mount brakes along with their SRAM drivetrain."

http://www.cyclingnews.com/features/...-bike-guide-1/


Campagnolo is used by three of 18 WorldTour teams. With teams going to discs, the number will drop further.

Dump Campy and get some nice Shimano wheels and Di2. It's totally unnecessary, but great for shifting under load -- and you get that little squeak when you shift gears. It's the sound of technology!


-- Jay Beattie.

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