[math2014]

Guys, i ve heard so many opinions.

Personally i got no experience from CF, i only know what i read.

If those BCD frames cost 2500$ and if they are 10x stronger than lets say an alloy Demo9 or Scream or M1 or V10 or any other big aluminium bike, then this means that its the last frame a DHer would ever want as far as durability goes.

Alex, if what you say is true about the 10x factor, then this thing should be stronger than bmw or ti bikes (hypothetical Ti dh frame). If that is the case, then i would be glad to buy one as my first and last dh frame.

Great job at this rig, nice engineering. I wonder what is the resistance to scratches, dents, dings, heat and direct sunlight.

If you could fill me in i d be grateful.

Yannis

 

[Metal]

Originally posted by ssaddict
Almost 1/4" if its just like my Inedible, you could literally take a baseball bat to the main tubes and you'd only hurt your hands. .


That beachcruiser and pixie bike don't count Sanjay

Those were both chromoly and both held up. The fork and front wheel on the Cruiser were another story.

 

[Mani_UT]

Originally posted by crashing_sux
I wonder why someone doesn't make a frame that's the same strength and half the weight or less. Seems like that would sell like hotcakes, if it could really be done although I have my doubts.

Give me a reasonnable budget (say 500K for design, dimensioning & calculs, material charactization, design for manufacturing, tool design, tooling, and finally prototypes) and I get you a bombproof 6/7lbs composite DH/heavy freeride frame...

Now bring on the cash

 

[- seb]

Originally posted by WestCoastHucker
those bars are also a ton lighter, not of comparable weight

Bollocks, EA70 = 250g. Monkeylite DH = 225g. 10% difference.

 

[crashing_sux]

Originally posted by WestCoastHucker
those bars are also a ton lighter, not of comparable weight

With the Easton EA70 Monkeybars weighing 250g and the EC70 Monkeylite DH composite weighing 225g the 10% difference seemed comparible to me, I guess it's a ton lighter to you.

I keep hearing about how tough CF is unless you do something stupid like crash and hit the component hard, but how can you really know? Even if someone is JRA people will always say that they must have crashed earlier, or installed it wrong, or damaged it in some way.

Seems like the only way to know would be to test the components on a stress testing machine fresh from the factory before they've ever been off road, wish someone would do that.

Oh yeah, it has been done and here are the results.....

The bars were subjected up to 1700 N load and stress cycle test on a
machine. They were tested through a simulated phase cycle to simulate
real world situation. Test cycle >200,000 were stopped, <25,000
cycles not suitable for off-road. Three sets of each item tested were ordered and tested directly out of the box, never ridden off road, crashed, or installed improperly. This is a test performed by a German bike mag a while back (those wacky Germans, always wanting real numbers instead of BS).

Check the numbers for yourself, the CF fatigue life, even from reputable manufacturers like Easton is all over the board while the aluminum is far more consistent. Which is really strange since we all know that CF has an incredible fatigue life and the breakages are always the riders fault, never the factory's.

I hear Easton won't warranty the bars, they claim the testing company must have crashed the testing machine :devil:

XC bars: (3 bars/stem sets, test to breakage cycles)
Easton EA70 (aluminum): 128252,140279,121074
Easton EC90 (carbon fiber): 35071, 4008, 56109
ITM Millenium Ultra Lite (aluminum): 12020, 12021, 11020
Race Face Air Alloy Straight (aluminum): 132261, 120240, 108213
Ritchey WCS Flat (aluminum): 44085, 44085, 44098
Roox DBS Cross Comp (aluminum): 8013, 12021, 19022
Syntace VRO Bar Carbon (carbon fiber): 195385, 178375, >200,000
Tune/Schmolke (carbon fiber): >200,000, 8013, 20038
X-Tasy CC Bar (aluminum): 4005,4005,4005

Freeride bars:
Answer Pro Taper (aluminum): 4007, 4005, 8013
Easton EA Monkey Bar (aluminum): 45820, 55890, 40077
Easton Monkey Lite DH (aluminum): >200,000, >200,000, >200,000
FSA FR275 (aluminum): >200,000, 180360, 188375
Race Face Low Riser (aluminum): 88173, 71140, 53887
Ritchey Pro Rizer (aluminum): 112222,56108, 140109
Syntace Vector Lowrider (aluminum): >200,000, 192382, >200,000
Tioga DH 286 OS (aluminum): 31815, 32032, 31893
X-Tasy DH Professional (aluminum): 198213, >200,000, 171338

 

[- seb]

Originally posted by ssaddict
Almost 1/4" if its just like my Inedible, you could literally take a baseball bat to the main tubes and you'd only hurt your hands. .

That seems a bold claim, is CF really that tough? I'd love to see someone do that

 

[crashing_sux]

Originally posted by ssaddict
Almost 1/4" if its just like my Inedible, you could literally take a baseball bat to the main tubes and you'd only hurt your hands. .

You should consider beating your bike with a carbon fiber baseball bat. Your hands won't hurt due to carbon fiber's superior vibration damping capabilities

 

[binary visions]

Originally posted by crashing_sux
the CF fatigue life, even from reputable manufacturers like Easton is all over the board while the aluminum is far more consistent.

You're looking at the MonkeyLite DH bar, so look at it.

Easton Monkey Lite DH (aluminum): >200,000, >200,000, >200,000

Now, Easton doesn't make a Monkey Lite DH bar that's aluminum, so I assume that must be a typo, considering that if its not, there are no carbon bars in the freeride test, which means the test is pointless.

Notice it's the only bar to consistantly not break in the testing cycles. That looks pretty consistent to me.

The EC90 is really not the point of this discussion, since the ultimate goal of that bar is extreme weight loss, not strength.

 

[WestCoastHucker]

Originally posted by - seb
Bollocks, EA70 = 250g. Monkeylite DH = 225g. 10% difference.

i bet it is slightly more than 10% after you add another inch to the EA 70 to make them the same size

and as binary also stated the EA 70 is designed to be light not strong

 

[- seb]

FWIW, I had a carbon monkeylite, and had a crash, and it snapped when I started riding the bike again. It wasn't down to my shoddy installation, I'm not a dick, I know what I'm doing. I was lucky not to do myself a serious injury. That doesn't mean I don't trust CF though - as far as breaking handlebars goes that's the worst impact I've ever had I think, it'd have bent an alu bar I'm sure.

link of bar-breaking account: http://www.ridemonkey.com/forums/showthread.php?s=&threadid=87609&perpage=15&pagenumber=2#post1127983

 

[- seb]

Originally posted by WestCoastHucker
i bet it is slightly more than 10% after you add another inch to the EA 70 to make them the same size

Still, it's comparable. That's why I really liked the monkeylites, they felt good and were nice and wide.

 

[ssaddict]

Originally posted by - seb
That seems a bold claim, is CF really that tough? I'd love to see someone do that

While I haven't actually done that to my Inedible, I have done it to a bike I made out of carbon.... I also used a hammer. The frame I made used a much smaller weave and less layers than Alex does.

But yes, I hit the frame with a alloy bat and the blunt end of a hammer more than a few times just to see what the hell would happen.

It hurt.


Carbon is a very cool material, but you got to understand it and respect it. Its not for everybody.

 

[math2014]

I just hope that someone with produce a Ti DH frame sometime...

 

[Joe Pozer]

Originally posted by math2014
I just hope that someone with produce a Ti DH frame sometime...

I thought Litespeed tried to a few years back...


That's a sweet looking frame...Can't wait to see Sanjay rippin' on it.

 

[math2014]

Originally posted by Joe Pozer
I thought Litespeed tried to a few years back...

to my best knowledge they made the Kitsumi a killer FR hardtail...

and now the Niota a 5x5 trailbike. Price is like an M1, longetivity? 30 times more than an M1.

 

[Zark]

Originally posted by math2014
I just hope that someone with produce a Ti DH frame sometime...

Litespeed did. It cost a LOT. The Machete I believe.

I think Bianchi did too.

Failed experiment. DH bikes are disposable ot a degree. You'll want a new one in 5 years anyway.

 

[bigshred]

all of these #'s and figures need to be viewed with scepticism! Carbon fiber can be extremely strong when tested in one direction (tension, compresion, torsion) which is dependent on the manufacturiong process. How the individual fibers are laid etc.. are all important in the final products figures. CF can be tested to have a stregth of XXXXX in one direction and only a strength of XX in another direction. During a crash a frame is subjected to numerous "non-riding" forces, which may go against its ten times as strong rating. just something to think about.

 

[Joe Pozer]

Okay, let me try this again...

The Litespeed Machete

 

[binary visions]

Originally posted by Joe Pozer
Okay, let me try this again...

The Litespeed Machete

Wow. That's fugly. I'm suprised, considering the company.

 

[Lexx D]

That's not a DH bike.

 

[Zark]

Originally posted by Lexx D
That's not a DH bike.

It was in '96

But then again I don't know ANYTHING about bikes

 

[binary visions]

Originally posted by Lexx D
That's not a DH bike.

It used to be.

 

[WestCoastHucker]

Originally posted by Joe Pozer
Okay, let me try this again...

The Litespeed Machete

holy crap... i was just staring at the pic, and i swear i saw the bike flex.....

 

[Lexx D]

Originally posted by Zark
It was in '96

But then again I don't know ANYTHING about bikes

now it makes sense, i think it was made by trek.

 

[binary visions]

Originally posted by WestCoastHucker
holy crap... i was just staring at the pic, and i swear i saw the bike flex.....

Ahahaha.. I was thinking the exact same thing.

 

[ÆX]

Originally posted by crashing_sux
With the Easton EA70 Monkeybars weighing 250g and the EC70 Monkeylite DH composite weighing 225g the 10% difference seemed comparible to me, I guess it's a ton lighter to you.

I keep hearing about how tough CF is unless you do something stupid like crash and hit the component hard, but how can you really know? Even if someone is JRA people will always say that they must have crashed earlier, or installed it wrong, or damaged it in some way.

Seems like the only way to know would be to test the components on a stress testing machine fresh from the factory before they've ever been off road, wish someone would do that.

Oh yeah, it has been done and here are the results.....

The bars were subjected up to 1700 N load and stress cycle test on a
machine. They were tested through a simulated phase cycle to simulate
real world situation. Test cycle >200,000 were stopped, <25,000
cycles not suitable for off-road. Three sets of each item tested were ordered and tested directly out of the box, never ridden off road, crashed, or installed improperly. This is a test performed by a German bike mag a while back (those wacky Germans, always wanting real numbers instead of BS).

Check the numbers for yourself, the CF fatigue life, even from reputable manufacturers like Easton is all over the board while the aluminum is far more consistent. Which is really strange since we all know that CF has an incredible fatigue life and the breakages are always the riders fault, never the factory's.

I hear Easton won't warranty the bars, they claim the testing company must have crashed the testing machine :devil:

XC bars: (3 bars/stem sets, test to breakage cycles)
Easton EA70 (aluminum): 128252,140279,121074
Easton EC90 (carbon fiber): 35071, 4008, 56109
ITM Millenium Ultra Lite (aluminum): 12020, 12021, 11020
Race Face Air Alloy Straight (aluminum): 132261, 120240, 108213
Ritchey WCS Flat (aluminum): 44085, 44085, 44098
Roox DBS Cross Comp (aluminum): 8013, 12021, 19022
Syntace VRO Bar Carbon (carbon fiber): 195385, 178375, >200,000
Tune/Schmolke (carbon fiber): >200,000, 8013, 20038
X-Tasy CC Bar (aluminum): 4005,4005,4005

Freeride bars:
Answer Pro Taper (aluminum): 4007, 4005, 8013
Easton EA Monkey Bar (aluminum): 45820, 55890, 40077
Easton Monkey Lite DH (aluminum): >200,000, >200,000, >200,000
FSA FR275 (aluminum): >200,000, 180360, 188375
Race Face Low Riser (aluminum): 88173, 71140, 53887
Ritchey Pro Rizer (aluminum): 112222,56108, 140109
Syntace Vector Lowrider (aluminum): >200,000, 192382, >200,000
Tioga DH 286 OS (aluminum): 31815, 32032, 31893
X-Tasy DH Professional (aluminum): 198213, >200,000, 171338

that is a example of strength of non welded alum.
something that most all dh bikes are. a welded alum
bar would have some diferent results.

i can't disclose how thick my tubes are. thick enough to
crash on some rocks and not get hurt. seth went otb on my 2x4 last year on the top of the waterfall in vt and had to walk 30 yards down the rocks to get it and it was fine.

 

[crashing_sux]

Originally posted by binary visions
You're looking at the MonkeyLite DH bar, so look at it....

... there are no carbon bars in the freeride test, which means the test is pointless.

Notice it's the only bar to consistantly not break in the testing cycles. That looks pretty consistent to me.

Wow, I guess we had completely different points then. My point is nothing to do with a certain bar, only that I think people tend to overstate carbon fibers abilities. And yes, I like carbon fiber.

Logically you can't prove a negative. Testing 3 bars and not having one break proves nothing, maybe there is only about one in ten that break spontaneously. Test 3 bars and having one break at a much lower number of stress cycles than the others does prove something however, that at the quality coming off bicycle production lines the fatigue resistance of CF stuff varies wildly.

Yes, carbon stuff can just spontaneously break while just riding along, a couple of the carbon bars broke after less than 10,000 cycles which the testers equated to just a few months of moderate off road riding.

Basic logic says that testing three bars and having them all do great doesn't mean that all of them are going to test strong, but testing 3 bars and having one of them break DOES prove that SOME of them do not have adequate fatigue strength.

And I'm not talking about bars here, just in general people are always talking about how CF has incredible fatigue resistance unless you crash, this test clearly shows that is not always true.

 

[binary visions]

Originally posted by crashing_sux
...Logically you can't prove a negative. Testing 3 bars and not having one break proves nothing, maybe there is only about one in ten that break spontaneously...

...Basic logic says that testing three bars and having them all do great doesn't mean that all of them are going to test strong, but testing 3 bars and having one of them break DOES prove that SOME of them do not have adequate fatigue strength...

Okaaayy..

If I can't prove that testing 3 bars and not having one break means they're strong, then you can't prove that testing three bars and having one break means a single thing. They are three bars out of however many hundreds or thousands that Easton made, so what if the one that broke was the only one that ever failed? Your logic is flawed. If you can't look at those three bars as a representative sampling, then you can throw the whole test in the trash. I understand what you are thinking, but the fact is you can't only look at the negative.

I do validations here at work all the time. When you take a sampling, it is intended to be representative of the whole, with a calculation for what the chances are that it really IS representative of the whole. So if I validate something and it passes, it means the whole is fine. If I validate something and one piece of data fails, I take another incremental set of data (say, another 10-20 data points), and if that passes, I still pass the validation. One piece of data failing doesn't mean the overall validation is bad or indicate that a lot will fail.

Besides, I honestly don't know what of the other freeride bars are carbon, but NONE of them are labeled carbon.. So what are the results for the other carbon freeride bars?

The XC bar test can be thrown in the trash for this discussion. The only reason people make XC bars out of carbon is so you can have a 90 gram bar on your 19.25lb hardtail. They aren't strong - they could be, but the manufacturers aren't targeting that group, they're targeting the weight weenies.

 

[Mani_UT]

about the strength of the CF bars:

2 issues:

A- the clamping: CF bars or anything CF for that matter are EXREMELY sensitive to the quality of the clamping mechanism. Any sharp angles, burr or defect on the clamp will dramatically lower the longevity of your bar!

B-Quality control. CF is great. Unlike aluminum or steel for that matter you define the properties of your material in the final stage of fabrication. deviation from the regular cure cycle, misplacement of some plies, defects in the bladder use for the forming of the bar, all can have desastrous effect on the quality of your piece. That kind of **** is really well controlled in the aerospace industry. How tightly controled is it when people produce a $10 CF bar in Taiwann? I'd think pretty (sic) bad.
When I trimmed my FSA K force bar to a narrower width, I alomst puked looking at the variations in the wall thickness. Scary...


edit: almost forgot: that's where the love somebody put in a product like a BCD counts: I am sure he pays close attention to what he is doing because he doesn't have an other thousand part to make before the end of the day. He also will notice anything wrong right at the fabrication step!

 

[Jm_]

Originally posted by math2014


If those BCD frames cost 2500$ and if they are 10x stronger than lets say an alloy Demo9 or Scream or M1 or V10 or any other big aluminium bike, then this means that its the last frame a DHer would ever want as far as durability goes.

Honestly, the one I saw had a ton of shock play. Whether this was due to abuse, manufacturing, or use, it was pretty bad, and because of that, it was definitely not the "last frame" anyone would want. Play wreaks havoc on the shock, eyelets, and other parts.

 

[- seb]

proper titanium DH frame:

http://www.batch.org/eng/projects.php?id=tension_dh

personally I can't see the point, ona DH frame you want super-stiff, which aluminium does well. As far as I'm aware, titanium doesn't.

 

[Rabie]

Originally posted by Metal
I have gone through my fair share of Aluminum frames.

[cough]

 

[Dingus McGee]

That is so fronj'd up! BCD and Metal will go down in MTB history this season, mark my words! Killer combo.

Ricky-racers nationwide are going to be shaking their heads in disbelief in the starting line and again later while they watch the podium.

 

[MikeD]

Originally posted by Dingus McGee
That is so fronj'd up! BCD and Metal will go down in MTB history this season, mark my words! Killer combo.

Ricky-racers nationwide are going to be shaking their heads in disbelief in the starting line and again later while they watch the podium.

I think BCD's best-ever marketing decision was getting Sanjay on one. The boy gets noticed, that's for sure. Gonna be a loooot of people making inquiries about bikes, and maybe even a few who buy them.

MD

 

[Kornphlake]

Originally posted by - seb
proper titanium DH frame:

http://www.batch.org/eng/projects.php?id=tension_dh

personally I can't see the point, ona DH frame you want super-stiff, which aluminium does well. As far as I'm aware, titanium doesn't.

It says their titanium is 5/2, I thought 6/4 was aerospace grade. We make some lights for subs the Navy uses and they're all 6/4. Tiodized black, talk about pure sex, mmm I'm going to go look at one right now.

 

[Dog Welder]

HEY BCD...just out of curiosity how many hours does it take you to make one of those frames?

Do you start with a premade molded CF frame parts, ie top tube, head tube, down tube, and just keep wrapping it in sheets of CF?

 

[MikeD]

Originally posted by Kornphlake
We make some lights for subs the Navy ... talk about pure sex, mmm I'm going to go look at one right now.

That's just kinda disturbing to read, especially if you've ever really been on a submarine...

MD

 

[Kornphlake]

Originally posted by MikeD
That's just kinda disturbing to read, especially if you've ever really been on a submarine...

MD

As I understand they're the unmanned type, like what you see on documentarys of the Titanic. Only owned by the military for whatever reason.

 

[MikeD]

Originally posted by Kornphlake
unmanned type

I thought you were talking about eunuchs for a second. I was REALLY confused.

MD

 

[Kornphlake]

Oh, now I get it, you're right the navy and sex and all that. Well anyways Titanium is cool for some stuff, I wouldn't buy a DH bike made out of it, I'd actually rather have carbon fiber.