You should look at this before buying carbon bicycle rims from china
#1
Junior Member
Thread Starter
Join Date: Jul 2016
Location: China
Posts: 14
Likes: 0
Liked 0 Times
in
0 Posts
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
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.
#2
Senior Member
Join Date: Mar 2016
Location: South Italy
Posts: 1,062
Bikes: BMC SLR01; Cannondale Trail; Custom steel gravel.... plus 5 vintage
Liked 169 Times
in
102 Posts
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....
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....
#3
Tortoise Wins by a Hare!
Join Date: Feb 2006
Location: Looney Tunes, IL
Posts: 7,398
Bikes: Wabi Special FG, Raleigh Roper, Nashbar AL-1, Miyata One Hundred, '70 Schwinn Lemonator and More!!
Liked 943 Times
in
505 Posts
Riders concerned about the risk of failure won't touch carbon rims. No good reason to.
#5
Veteran, Pacifist
Join Date: Dec 2004
Location: Seattle area
Posts: 13,843
Bikes: Bikes??? Thought this was social media?!?
Liked 5,860 Times
in
2,509 Posts
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.
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.
__________________
Vintage, modern, e-road. It is a big cycling universe.
Vintage, modern, e-road. It is a big cycling universe.
#7
Veteran, Pacifist
Join Date: Dec 2004
Location: Seattle area
Posts: 13,843
Bikes: Bikes??? Thought this was social media?!?
Liked 5,860 Times
in
2,509 Posts
#9
Senior Member
Join Date: Jan 2017
Location: Rochester ,NY
Posts: 103
Bikes: Mongoose Reform Sport
Likes: 0
Liked 0 Times
in
0 Posts
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
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
#10
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.
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.
#11
Forum Moderator
Join Date: Jul 2007
Location: Kalamazoo MI
Posts: 21,172
Bikes: Fuji SL2.1 Carbon Di2 Cannondale Synapse Alloy Viscount Aerospace Pro Raleigh C50 Cromoly Hybrid Legnano Tipo Roma Pista
Liked 7,512 Times
in
4,198 Posts
Enough is enough.
Closed thread.
Closed thread.