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Anyone see these carbon chainrings?(13 posts)

Anyone see these carbon chainrings?Sprint-Nick
Aug 31, 2003 2:50 PM
On velonews in their eurobike coverage they had these carbon chainrings. I wondow what durability would be like at only 61 grams for the pair.
... I had seen the same or similar product a few years ago...Akirasho
Aug 31, 2003 3:51 PM
... and they were essentially a one time use, throw away item (for Pros or Nutz looking for the nth degree of gram savings).

... Even at a Pro/Cat 1 level... I'd be leary of balancing light weight against a DNF cuz your teeth had a bit of decay...

OTOH, someone somewhere is working on alloy teeth bonded to a CF carrier...

Be the bike.
re: Anyone see these carbon chainrings?DERICK
Aug 31, 2003 5:09 PM
Here's the site selling them and lots of other way cool carbon fiber bike parts. They have those cranks too.
http://www.poshbikes.com/index01.html
re: Anyone see these carbon chainrings?kneebreaker
Sep 1, 2003 12:56 AM
its only a sheet of carbon laid over cnc maching aluminum chain rings. what purpose would it have except for somthing nice looking but peeling off a month after.
Not true.DERICK
Sep 1, 2003 5:13 AM
This is taken from the website.

"These carbon rings are CNC machined from specially laminated carbon fibre sheets, which are hand laid, using a mixture of woven and random weave material. As standard woven carbon sheet, would allow the ring to flex or crack along the unified weave direction.
Use: These chainrings are designed for weight saving purposes only! and are therefore less durable than alloy chainrings. We have customers who have been racing competitively on these rings over long distances without failure, but this is not recommended."
So when your buddy wants to pick your bike up to see..the bull
Sep 1, 2003 6:13 AM
how much it ways you say,"hang on".
Then you pull your water bottles out and install the carbon chainrings.After he has picked it up and said,"Wow thats light".You put your real rings back on.
Oh yeah and dont forget to swap out a real cassette with a full Ti one too! :)
Yes turekneebreaker
Sep 1, 2003 11:11 AM
you wrote it. laminated over cnc. laminated is a sheet of carbon over aluminum.

its like a sheet of wood laminated over plastic inside of cars.

looks nice but is not the real thing.

just doesn't make any performance enhancement. it only looks different.

remember carbon fiber made right is not lighter than the lightest aluminum alloy. a 7075 chain ring made well is lighter. this is compared to a properly rapped carbon pc using many wovern fibers.
Re-read it !DERICK
Sep 1, 2003 5:09 PM
CNC is the machining process, NOT the material being machined. CNC stands for Computer Numeric Control. It's basicaly a process where a computer controls a cutting tool which removes material until a desired shape is achieved.

It doesn't say anywhere that there is aluminum used in them. Look closely at the teeth. They are carbon, not aluminum.

I do agree that they are pretty much useless. You won't find any on my bike.
did you -read it ! or understand itkneebreaker
Sep 1, 2003 8:27 PM
this is getting to be pointless.

have you ever cut carbon fiber? if you did you would understand the cnc process would mutilate solid carbon with this thickness. it is pure carbon fabric layers over each other, not a chunk of solid matter. it's not the same as fiberglass.

for example. if you check the easton web sight. it will read, if you over titen a carbon seat tube it will crack and slice in half. this is a less stressful than doing a cnc cut on carbon.

do you know what laminated means? if not check your drivers licence.

end of story.
Dude, It's carbon.Synchronicity
Sep 1, 2003 9:59 PM
Yes carbon through and through, apart from the resin matrix of course.

One of my best quotes comes from my mum: It goes like this:
"never assume anything"

Kneejerker, you're /assuming/ that because you don't /think/ a CNC machine would be able to cut a carbon composite, it must have a core of aluminium.

Just because CNC isn't normally done on carbon doesn't mean it can't be done. They' probably use a different shaped cutter & speed of cutting.

Man they REALLY look like genuine carbon fibre composite teeth to me. It's not that fake carbon "looking" stuff (or even one layer of carbon weave) over the top of aluminium. It's many sheets of carbon weave layers laminated TO EACHOTHER.

But look. Most of us agree that no matter what they're made of they're useless anyway. OK?
i see synchronicity likes to change names as well as thruth!kneebreaker
Sep 2, 2003 1:18 AM
do you really need to insult people by manipulating a name we use on this board? seems to me you must have stayed in grade school.
Sorry, a kneejerker is just a reaction to something hilarious.Synchronicity
Sep 2, 2003 5:09 PM
Its just a term used when you totally kak yourself laughing.
Nothing dergoratory. Just thought some other's may get a laugh from it.

Still doesn't change my argument though. I've had another look at those chainrings. You can actually see where the direction of the weave continues into the teeth from the unmachined section. IF this is fake carbon, or even just one layer of weave "laminated" to alloy, they've done a **mighty** fine job of matching the direction of the ply angles, ALL the way around the chainring.
did you -read it ! or understand itDERICK
Sep 2, 2003 4:29 AM
You've already made it clear that you know nothing about machine work with your "CNC means layering" comment. Now you're saying carbon fiber can't be machined. You base this on the fact that a CF seatpost can be cracked if overtightened? You're talking about totally different forces. There's no connection. Carbon fiber tubes are cut all the time. Machining is nothing more than complex cutting.

DO you know what laminated means. It's layers of material bonded togerter. Laters of wood are laminated all the time and then cut, carved and routered. no different than machining.

I don't think anyone would argue when we say they are impractical but they at least deserve an accurate description.