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You should look at this before buying carbon bicycle rims from china

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You should look at this before buying carbon bicycle rims from china

Old 03-10-17, 05:42 AM
  #1  
Bruce su
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You should look at this before buying carbon bicycle rims from china

Hi guys, how's everything going with you? My name is Bruce, I would like to share some carbon bicycle rims knowledge with you, hope it can help you make a right decision when buy carbon rims from China.

The traditional production technology used EPS foam preform technology to produce the rims, one drawbacks of this kind of technology is the EPS foam inside the rims, in order to take the foam out and remove the debris, workers need to open lid on the rim( as the following picture shows), the rim will break easily because of the opened lid when tire pressure or temperature is too high.
Open Lid Carbon Rims.jpg
Problems for Bad Rims.jpg

As the development of production technology, most factories have abondoned this traditional technology and used a new technology, called one-time moulding technology, which can add more strength and beauty to the rims, the average compressive strength without opening the lid is more than 20% compared to the open lid.

Another important point is the production of tyre channel. In order to save cost, some factories will use Silicom moulding technology to produce the rim, which have obvious cut on the tire channel, it will easily cut the tire and make the thickness of brake surface uneven and make the wheel unstable, while professional manufacturers will use three pieces technology (as the following picture shows) to make the tire channel,which can make rims more beautiful and stronger.
rim difference.jpg
Three pieces.jpg

What's more, in order to control the quality of carbon rims, professioal manufacturers will do a lot of tests,such as spoke tesion, brake surface, rim roundness and flatness tests when rims are finished, as the pictures shows.
Carbon Rim Production.jpg
Rim Test Methods.jpg

Last edited by Siu Blue Wind; 03-10-17 at 07:02 AM.
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Old 03-10-17, 08:40 AM
  #2  
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Hi Bruce , i don't want to be rude but for me this looks like a self promoting post.
To be honest i have a loot of china-part on my bike but those are just accessory , i never will have the feel of security with a pair of complete rims/wheels from china.

Let's face in this way , actually 70% or more of bikers are affected by the marketing and pros.
I don't want to trade my security for the coolness of a couple of high-profile-carbon-wheels i'll use my ugly-heavy-definitrely-not-aero as long i can and when it's time for upgrade i prefer some famous brand not any cheap or no brand.

If a cheap bottlecage will break i just lose my bottle , but i don't want to think what i'm going to lose if a cheap wheels will break during a discend at 60+kmh....
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Old 03-10-17, 09:00 AM
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Riders concerned about the risk of failure won't touch carbon rims. No good reason to.
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Old 03-10-17, 09:24 AM
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Bruce, take your sales pitch elsewhere. Not a carbon guy.
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Old 03-10-17, 09:55 AM
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I read your post 3 times.
You show some pics and talk about process.
What is the conclusion?

"Most factories have abandoned this technology" - Assuming you know every manufacturers' process, which factories are using the new technique? Which are using the old method?

Assuming you have legitimate credentials and current info - what is the message you are sending?
Most of us are not engineers, know nothing about carbon wheel manufacturing specifications, are not qualified to inspect wheels, and generally cannot "look before buying carbon bicycle rims". Are you giving us a "BUY" or "DON'T BUY" message.
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Old 03-10-17, 10:19 AM
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Originally Posted by Wildwood View Post
Are you giving us a "BUY" or "DON'T BUY" message.

Notice that the OP was edited by a forum moderator. If I were a betting man I would wager that the original post contained a link or something else promoting a product.
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Old 03-10-17, 10:31 AM
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Originally Posted by indyfabz View Post
Notice that the OP was edited by a forum moderator. If I were a betting man I would wager that the original post contained a link or something else promoting a product.
Missed that.
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Old 03-10-17, 10:32 AM
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SPAM. Please remove thread.
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Old 03-10-17, 07:34 PM
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Originally Posted by Bruce su View Post
Hi guys, how's everything going with you? My name is Bruce, I would like to share some carbon bicycle rims knowledge with you, hope it can help you make a right decision when buy carbon rims from China.

The traditional production technology used EPS foam preform technology to produce the rims, one drawbacks of this kind of technology is the EPS foam inside the rims, in order to take the foam out and remove the debris, workers need to open lid on the rim( as the following picture shows), the rim will break easily because of the opened lid when tire pressure or temperature is too high.
Attachment 555454
Attachment 555456

As the development of production technology, most factories have abondoned this traditional technology and used a new technology, called one-time moulding technology, which can add more strength and beauty to the rims, the average compressive strength without opening the lid is more than 20% compared to the open lid.

Another important point is the production of tyre channel. In order to save cost, some factories will use Silicom moulding technology to produce the rim, which have obvious cut on the tire channel, it will easily cut the tire and make the thickness of brake surface uneven and make the wheel unstable, while professional manufacturers will use three pieces technology (as the following picture shows) to make the tire channel,which can make rims more beautiful and stronger.
Attachment 555460
Attachment 555457

What's more, in order to control the quality of carbon rims, professioal manufacturers will do a lot of tests,such as spoke tesion, brake surface, rim roundness and flatness tests when rims are finished, as the pictures shows.
Attachment 555458
Attachment 555459
Could you please make the pictures smaller ? And yes this is sarcasm.
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Old 03-10-17, 07:45 PM
  #10  
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I was actually interested in this thread because I'm an engineer with 3 sets of carbon road wheels. And I worry about wheels (carbon or otherwise) when I'm traveling warp speed down 3,000 ft descents.

I read the OP's text 3 times and it is absolutely unintelligible. I assume this was originally drafted in some other language and Google-translated successively into Icelandic and then Swahili, Bhutanese, and then English.
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Old 03-10-17, 07:52 PM
  #11  
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Enough is enough.

Closed thread.
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