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Carbon handlebar for DH?

Biffff

Monkey
Jan 10, 2006
913
0
true.dat

I believe the concensus is nooooooo! Catastrophic failure is no fun.
Ohhhhhhhhhhh dear. Carbon is wicked strong. Easton CNT Monkey DH bars are basically the strongest bar made. I researched extensively on this board and others and couldn't find anybody who had broken one or knew of anyone who had, or heard a rumour that one had broken one time. Most Carbon bars are designed for XC use, but if you can't trust a Monkey DH bar for extrem riding I'm not quite sure you should be riding a bike.
 

DHS

Friendly Neighborhood Pool Boy
Apr 23, 2002
5,094
0
Sand, CA
I have seen a couple snapped, yes, actually seen. and i have dealt with a couple coming into my shop. but its still not enough to worry. the stuff i've seen them go through. makes me completely trust the bar.

the ones i've seen snapped was just over abuse. scratched up. with the rest of the bike not taken care of at all.

i have a carbon bar on every one of my bikes. always will.
 
Jan 18, 2006
89
0
I agree, I have the CNT Easton bars on all my bikes and have taken some horrendous crashes that I am not proud of. The bars are a little scratched but still solid and strong. The CNT makes a huge difference, there is no apparent weave like traditional carbon bars. Very strong, very expensive.
 

Arkayne

I come bearing GIFs
May 10, 2005
3,738
15
SoCal
I've stirred the hive! I suppose it's personal bias based on early carbon bars. True, the new bars are much better as long as they are torqued and unabused (dings/scratches). Regardless, I still would have a hard time trusting a CF bar for DH or street use.
 

Bulldog

Turbo Monkey
Sep 11, 2001
1,009
0
Wisconsin
I've stirred the hive! I suppose it's personal bias based on early carbon bars. True, the new bars are much better as long as they are torqued and unabused (dings/scratches). Regardless, I still would have a hard time trusting a CF bar for DH or street use.
So after your comment about failures that means you only run heavy steel bars on every one of your bikes right?
 

demo 9

Turbo Monkey
Jan 31, 2007
5,910
46
north jersey
i snapped a carbon seatpost. just throwing that out there. i was bouncing up and down on the susupension and it just snapped off
 

Alloy

Monkey
Aug 13, 2004
288
0
thousand oaks, ca
I made a guy snap his... he was going to follow me to get the right speed for a road gap in Whistler. At the last minute I noticed someone had put a rope over the take off. ...A rope that wasn't there all day. So with no other option I go around and slam hard through a water channel and ride a nose wheel off course. I look behind me and the dude who was following is running at 25 miles an hour without his bike. Turns out he snapped his carbon bars and was forced to dismount.

Also saw a guy in Tahoe with snapped bars... He rode pro and was going for the man line in the race... his bars couldn't take the hit and he went down pretty hard.
 

dirttastesgood

Turbo Monkey
Dec 12, 2006
1,517
0
CT
I don't disagree that they are strong but there are some of us who put nicks and dents in metal bars like its our job. I don't think CF is for us.
 

Damo

Short One Marshmallow
Sep 7, 2006
4,603
27
French Alps
I won't use them, but not for strength reasons:
The rise is a bit too high (25.4mm), they are quite narrow (710mm), only weighing in at 225g is good though. But for 130euros?

Here: Burgtec Ride Wides are a good low-rise (20mm), wide (750mm) and only weigh 40g more than the Eastons! Trim them down to the Easton's 710mm and they'll probably be lighter than the 225g! Big plus: 95euros.

And Scandium alloy? No problems if you have a few scratches. I can imagine scratching a carbon bar and constantly worrying about it's structural integrity after...
 

JohnnyC

Monkey
Feb 10, 2006
399
1
Rotorua, New Zealand
Ohhhhhhhhhhh dear. Carbon is wicked strong. Easton CNT Monkey DH bars are basically the strongest bar made. I researched extensively on this board and others and couldn't find anybody who had broken one or knew of anyone who had, or heard a rumour that one had broken one time. Most Carbon bars are designed for XC use, but if you can't trust a Monkey DH bar for extrem riding I'm not quite sure you should be riding a bike.
I've seen a set of the Easton CNT Dh bars break after a WEEK of use, put me well off Carbon bars for downhilling
 

joelsman

Turbo Monkey
Feb 1, 2002
1,369
0
B'ham
I have been using a set of Gravity carbon bars for over a year with no problems, however if I ever scratch them deep they are getting removed for sure.
 

dhkid

Turbo Monkey
Mar 10, 2005
3,358
0
Malaysia
I can imagine scratching a carbon bar and constantly worrying about it's structural integrity after...
i though all that has been covered ages ago?

just from a design point of view, (assuming that the products you are talking about are actually designed properly) aluminum will be designed with the load it has to take in mind. cfrp would be designed around fatigue. and due to the nature of the material, it would be much stronger then its needed to be to meet the fatigue criteria.

this is of course assuming its done right. i remember the maker of lahar saying that the frame is actually about 5 times stronger then it needs to be. well, also maybe coz thin carbon fiber + rocks dont go well together.
 

Huck Banzai

Turbo Monkey
May 8, 2005
2,523
23
Transitory
"I knew a guy, whose dog's previous owner ran carbon which failed and his whole family spontaneously combusted."

"I saw a guy lose both his hands installing his carbon bars because he didnt use a torque wrench."

I _____ a guy who ______ and _____ his _____.


---

Pricewise - Burgtecs are about 140$ US, Monkeylites 100-140 depending where you got em. I dont think your saving 58g by cutting an inch of them though, but who knows, eh?
 

Damo

Short One Marshmallow
Sep 7, 2006
4,603
27
French Alps
i though all that has been covered ages ago?

just from a design point of view, (assuming that the products you are talking about are actually designed properly) aluminum will be designed with the load it has to take in mind. cfrp would be designed around fatigue. and due to the nature of the material, it would be much stronger then its needed to be to meet the fatigue criteria.

this is of course assuming its done right. i remember the maker of lahar saying that the frame is actually about 5 times stronger then it needs to be. well, also maybe coz thin carbon fiber + rocks dont go well together.
What does this prove/disprove?
 

dhkid

Turbo Monkey
Mar 10, 2005
3,358
0
Malaysia
well, first of i forgot to say that carbon fiber parts dont suddenly fail with scratches on them. its just a myth.

the point was that carbon fiber parts when compared to aluminum parts will be stronger. and carbon fiber parts should be designed to take some damage.

of course there are parts which are designed badly or manufactured badly.

the whole post wasn't directed at you, just trying to clear things up. thats all.
 

Damo

Short One Marshmallow
Sep 7, 2006
4,603
27
French Alps
No worries.

Would an over-built carbon bar weighing the same as an alloy bar negate the purpose of having carbon in the first place?
 

Kntr

Turbo Monkey
Jan 25, 2003
7,526
21
Montana
A few years ago, I broke my EC70 in about a week. Ive been riding for over 10 years. Ive bent a few aluminum bars, but I have NEVER broke one until I tried carbon.

I really dont see the benefit to running carbon when the EA70 is only 20 grams heavier.

I dont disagree that a carbon bar is stonger, when it comes to NORMAL forces. When it comes to a odd force from an odd angle is when they break. Mine broke when I tipped over on a skinny. An aluminum bar would have never broke in that situation.

Why even risk it for 20-30 grams?
 

dhkid

Turbo Monkey
Mar 10, 2005
3,358
0
Malaysia
No worries.

Would an over-built carbon bar weighing the same as an alloy bar negate the purpose of having carbon in the first place?
no, not really, easton carbon bars are already overbuilt and still are lighter. i am not sure if they still mention on their web site but they used to say that their carbon bars were about 2 times the strength of their aluminum bars.

another advantage of carbon is that it supposedly helps filter out the smaller vibrations that the tires and suspension dont. i cant say that would be a huge advantage in dh, i did feel it when i first changed to carbon bars. its basically that they are not as stiff as aluminum.

you can ask any knowledgeable xc rider on the legendary combination of a ti stem and carbon bars.



kanter, yea, carbon, especially unidirectional weave, which the new carbon bars are made from are crap at taking loads their not designed for. its like using a piece of wood to take loads perpendicular to its grain, well, actually its the same thing. fiber/grain orientation dictates how the load will be carried.
 

limitedslip

Monkey
Jul 11, 2007
173
1
Can you cut a carbon bar, or does it ruin the structural integrity?

edit: nm, found a cutting carbon bars thread.
 

primo661

Monkey
Jun 16, 2008
412
0
Pietermaritzburg, South Africa
Theres a guy over here riding Greg Minnaars old Orange 222 practice bike, still with the original monkey lite carbon bars for 2001. They're scratched to **** and chipped but they still doing great! I'd class this guy as a first class hacker too, so it doesn't have an easy life. I'd trust carbon on my dh sled any day.
 

norbar

KESSLER PROBLEM. Just cause
Jun 7, 2007
11,346
1,587
Warsaw :/
Theres a guy over here riding Greg Minnaars old Orange 222 practice bike, still with the original monkey lite carbon bars for 2001. They're scratched to **** and chipped but they still doing great! I'd class this guy as a first class hacker too, so it doesn't have an easy life. I'd trust carbon on my dh sled any day.
Same for me. I'm not a hack but I've had 2 very hard crashes this year and in both cases the bars took direct hits. My monkey lites hold great even after being scratched as hell. As far as I know easton composites are also much much stronger than regular carbon. - Actualy a friend who practices archery told me that when you shoot normal carbon arrow into a wall or other hard object it will break while eastons simply bounce off unharmed. He probably lurks somewhere around here so I there is something I didn't say He'll correct me ;)


BTW. Does any1 know of gravity orientet Flat carbon bars? (Or if easton finaly finds out that ppl want their bars to be lower)
 

William42

fork ways
Jul 31, 2007
3,908
634
I might get flamed for this, but am I the only one who doesn't buy bars for weight? I buy my bars exclusively with rise, width, and sweep in mind. I like the idea of a carbon bar that damps vibrations, but until somebody comes out with a well shaped bar (for my prefs) I'll stick to my v1's with 17mm rise 29 1/2 inch wide bars
 

Zark

Hey little girl, do you want some candy?
Oct 18, 2001
6,254
7
Reno 911
It's a moot point, no one makes a 29" wide carbon bar that I know of.
 

norbar

KESSLER PROBLEM. Just cause
Jun 7, 2007
11,346
1,587
Warsaw :/
I'm in the 225+ club.

I want to live.
Know a guy in that range with answer bars and so far he lives.

It's a moot point, no one makes a 29" wide carbon bar that I know of.
Heard rumors of a carbon flat bar with width up to 730 or 750mm. Chromag or sth?
 

kuksul08

Monkey
Jun 4, 2007
240
0
I crashed my bike hard enough to crack the steerer tube, but the Azonic ST-1 bars are still fine. They are super beefy, and have an aluminum collar at the stem.
 

DirtyMike

Turbo Fluffer
Aug 8, 2005
14,437
1,017
My own world inside my head
The problem I have with carbon parts on a DH bike is simple, WHile is is as strong, or stronger than Aluminum, when it fails, it always fails big. Carbon doesnt dent, it doesnt bend, when it goes its BROKEN. Nicks/scratches, it all depends on how deep they are, just like with aluminum. The biggest reason I have seen for carbon failure on DH bikes is actually pretty simple, OVERTIGHTENING. Either of the stem clamp, brake levers seat clamp whatever, should be an obvious reason why that would cause a failure.