[SuspectDevice]

This thread is very heavy with inaccurate and mis-informed statements.

It's not even worth addressing them- but any material can be good or bad for building bikes, and carbon is certainly the best if you take ease of manufacture and simplicity of design out of the equation. Come on people, I know we are cynical here on Ridemonkey, but SantaCruz and their manufacturing partners are top-fricking notch.

 

[wiscodh]

This thread is very heavy with inaccurate and mis-informed statements.

i wanted to say the same thing but i am skered of the wrath of the armchair composites engineers on the monkey.

 

[IH8Rice]

but SantaCruz and their manufacturing partners are top-fricking notch.

but but but the internets said otherwise

 

[Pegboy]

At this time I kinda wonder what the point would be. People are able to get bikes down in the mid to high 30# mark without much trouble. The top pros only need to make top to bottom for 1 run so they are able to risk things even further when it comes to components etc. I personally know a few people who have built super light bikes only to end up adding back some weight mainly because the bike felt worse at the lighter weight (36# neighborhood). I could see possibly developing a new bike, and or design, that ended up being manufactured out of carbon, but to take a current design (such as the V10) and have a carbon offering seems redundant and a waste of manufacturing time and money...I just don't see much of an advantage.

As far as longevity and strength are concerned, carbon is fine. This notion of it exploding after an impact is a little far fetched. I know people that run hundreds of miles on carbon fiber feet that are scarred up from trail running and rocks etc., with no issue. Granted, the forces are different but 170-180 lbs deflected a million plus times without issue shows that the stuff is not as fragile as people think. Christ, if you subscribe to the typical RM philosophy, one would think that carbon fails so quickly and catastrophically that not only will it kill the rider, but it will also take their closest loved one as well.

 

[time-bomb]

At this time I kinda wonder what the point would be. People are able to get bikes down in the mid to high 30# mark without much trouble. The top pros only need to make top to bottom for 1 run so they are able to risk things even further when it comes to components etc. I personally know a few people who have built super light bikes only to end up adding back some weight mainly because the bike felt worse at the lighter weight (36# neighborhood). I could see possibly developing a new bike, and or design, that ended up being manufactured out of carbon, but to take a current design (such as the V10) and have a carbon offering seems redundant and a waste of manufacturing time and money...I just don't see much of an advantage.

As far as longevity and strength are concerned, carbon is fine. This notion of it exploding after an impact is a little far fetched. I know people that run hundreds of miles on carbon fiber feet that are scarred up from trail running and rocks etc., with no issue. Granted, the forces are different but 170-180 lbs deflected a million plus times without issue shows that the stuff is not as fragile as people think. Christ, if you subscribe to the typical RM philosophy, one would think that carbon fails so quickly and catastrophically that not only will it kill the rider, but it will also take their closest loved one as well.

I think you make some interesting points here. But one other factor to consider is the riding characteristics of carbon fiber vs. other materials. They ride and feel very different than Al and Steel. As steel is more forgiving that Al, carbon fiber is even more forgiving than steel. Carbon Fiber has no resonating frequencies. It dampens everything you ride over. So for me, even if weight, strength and cost were all the same (assuming it is a well designed bike), I would still argue that there is a benefit to carbon. I don't think the benefit will make you much faster but it may fatigue you less. I see this being a bigger advantage for long rides or XC. To me the biggest benefit if all other things are equal would simply be comfort. I have ridden a couple Carbon frames (not for DH though) and wouldn't have a problem going back.

 

[wood booger]

At this time I kinda wonder what the point would be. People are able to get bikes down in the mid to high 30# mark without much trouble. The top pros only need to make top to bottom for 1 run so they are able to risk things even further when it comes to components etc. I personally know a few people who have built super light bikes only to end up adding back some weight mainly because the bike felt worse at the lighter weight (36# neighborhood). I could see possibly developing a new bike, and or design, that ended up being manufactured out of carbon, but to take a current design (such as the V10) and have a carbon offering seems redundant and a waste of manufacturing time and money...I just don't see much of an advantage.

As far as longevity and strength are concerned, carbon is fine. This notion of it exploding after an impact is a little far fetched. I know people that run hundreds of miles on carbon fiber feet that are scarred up from trail running and rocks etc., with no issue. Granted, the forces are different but 170-180 lbs deflected a million plus times without issue shows that the stuff is not as fragile as people think. Christ, if you subscribe to the typical RM philosophy, one would think that carbon fails so quickly and catastrophically that not only will it kill the rider, but it will also take their closest loved one as well.

True, but most of those DH bikes in the high 30# area are pretty damn fragile. I know the Trek Session can crack and crumple pretty quickly. To get alloy DH frames to this weight the tubing wall thickness can get pretty minimal.

What carbon can allow is a frame of the same weight (or lighter), but with greater overall strength/stiffness (if designed correctly) and with much greater fatigue strength/life. A lighter, stronger frame that really does smooth out the ride.

I bet that any carbon DH bike that comes out of SC will be bomb proof. Take the V-10, lop off a pound or two, improve frame characteristics, improve asthetics, increase frame life, who doesn't want that?

 

[demo8razor]

I think you make some interesting points here. But one other factor to consider is the riding characteristics of carbon fiber vs. other materials. They ride and feel very different than Al and Steel. As steel is more forgiving that Al, carbon fiber is even more forgiving than steel. Carbon Fiber has no resonating frequencies. It dampens everything you ride over. So for me, even if weight, strength and cost were all the same (assuming it is a well designed bike), I would still argue that there is a benefit to carbon. I don't think the benefit will make you much faster but it may fatigue you less. I see this being a bigger advantage for long rides or XC. To me the biggest benefit if all other things are equal would simply be comfort. I have ridden a couple Carbon frames (not for DH though) and wouldn't have a problem going back.

i thought aluminum frames had a bit of flex to them at times or were almost soft? carbon is extremely rigid as you know. in other applications, skis/snowboards and boats. carbon is not a damp material what so ever and other materials must be used to make said object more damp. in skis and snowboards, titanal is used to create equipment that is very damp.
as i said with boats, carbon may be used for weight and overall stiffness for long areas, but in areas where there needs to be flex aramid is used due to its properties of basically giving but never breaking or coming apart.

 

[demo8razor]

Compared in what way?

when you weigh them. or to get the same strength a lot more kevlar is needed, but kevlar will not come apart like carbon. each laminate material has its pros and cons. carbon is very stiff and light the stiffness also becomes a con. kevlar is heavy but not as stiff and will not come apart. each was developed for different applications. newer fiberglass weaves or patterns are also negating the benefits of using carbon and kevlar in some applications.

 

[demo8razor]

Right and wrong IMO. Let's assume your not using carbon for making a super light DH bike (which you could for a WC racer like you say) and you then have more than enough room for impacts in a 40lb carbon bike. Lahars last forever, and I bet these Fury's will too.

well yes, that is true, by impacts i mean more or less any composite will generally have more damage from hitting say rocks than a metal will. when i say impacts i dont mean carbon is going to blow apart on you completely either, just that what have been scratches on my bike ,with a carbon frame would not just be scratches, they would need to be addressed.

 

[time-bomb]

i thought aluminum frames had a bit of flex to them at times or were almost soft? carbon is extremely rigid as you know. in other applications, skis/snowboards and boats. carbon is not a damp material what so ever and other materials must be used to make said object more damp. in skis and snowboards, titanal is used to create equipment that is very damp.
as i said with boats, carbon may be used for weight and overall stiffness for long areas, but in areas where there needs to be flex aramid is used due to its properties of basically giving but never breaking or coming apart.

You're right when talking about stiffness. However, it is a matter of simple harmonics. Titanium, aluminum, and steal all act like conductors when given inputs - audio or physical. This can easily be measured using any of these materials and some basic sound equipment. Input from impacts on the trail will have the same effect. They vibrate and they travel. Carbon Fiber has no resonating frequency and therefore has a damping effect on all inputs. You can even hear the difference when you are riding. I am not saying you won't feel anything at all, you just won't get all the feedback or vibrations when riding on a carbon fiber frame. You get the same effect w/carbon fiber handle bars.

Therefore, any type of shock or vibration travels throughout and is then transferred to the rider on a metal frame. If you have been riding Al bikes for years you don't notice it as much because you are used to it. But I guarantee you will notice a difference if you do an A/B test.

Makes me wonder, who is going to be the first to make a bike frame out of MDF?

 

[Whoops]

"Carbon Fiber has no resonating frequencies"

say what now?

 

[demo8razor]

You're right when talking about stiffness. However, it is a matter of simple harmonics. Titanium, aluminum, and steal all act like conductors when given inputs - audio or physical. This can easily be measured using any of these materials and some basic sound equipment. Input from impacts on the trail will have the same effect. They vibrate and they travel. Carbon Fiber has no resonating frequency and therefore has a damping effect on all inputs. You can even hear the difference when you are riding. I am not saying you won't feel anything at all, you just won't get all the feedback or vibrations when riding on a carbon fiber frame. You get the same effect w/carbon fiber handle bars.

Therefore, any type of shock or vibration travels throughout and is then transferred to the rider on a metal frame. If you have been riding Al bikes for years you don't notice it as much because you are used to it. But I guarantee you will notice a difference if you do an A/B test.

Makes me wonder, who is going to be the first to make a bike frame out of MDF?

i guess what i am thinking of is more or less the stiffer carbon object be it a snowboard does not track the snow as well as the titanal board, because the titanal makes that board damper and less sensitive to bumps and vibrations caused by said bumps or uneven snow.

we are talking about two different things in a sense. in a bike what i am talking about probably does not play into it as much.

 

[IH8Rice]

"Carbon Fiber has no resonating frequencies"

say what now?

only the brown noise effects it

 

[no skid marks]

My Lahar took an amazing beating, and had less surface dmage from rock interactions than an ally bike would have, as all the components looked more beaten than the frame.
Yes, carbon can have unseen damage, but we're talking impacts that would severely damage an ally frame anyway.
Put a small nik at the top of some tin foil, and do the same with paper. Pull on both sides of the nik, what tears quicker?
Carbon can be made to have many qualities, and can help strongly in bike designs from it's moldability.
Longevity is not an issue we should be concerended with due to it being carbon, but we should be concerned with it's manufacturing quality.
Carbon has a higher fatigue life within it's elastisity than ally.

 

[Pegboy]

I have to preface this statement by saying that I've never ridden a full suspension carbon bike, never mind a DH bike. I have ridden aluminum and carbon road bikes and I can say the difference is night and day..mostly from a damping comfort standpoint. Having said that, I question if the difference would be that great on a DH bike. Most bikes have at least 8" in the front and rear of the bike that absorb these vibrations that are continually being brought up. Couple that with multiple pivots, links and bearings that will discipate the vibrations, I wonder, once again, if there will be that big a difference.

 

[JRogers]

I have to preface this statement by saying that I've never ridden a full suspension carbon bike, never mind a DH bike. I have ridden aluminum and carbon road bikes and I can say the difference is night and day..mostly from a damping comfort standpoint. Having said that, I question if the difference would be that great on a DH bike. Most bikes have at least 8" in the front and rear of the bike that absorb these vibrations that are continually being brought up. Couple that with multiple pivots, links and bearings that will discipate the vibrations, I wonder, once again, if there will be that big a difference.

Yes, I think this is correct. Even on road bikes, although frame material is quite important, it is not (IMO) nearly as important as all the other variables put together: tire size and pressure, bar, tape, stem, seatpost, saddle...Also, carbon road frames are not automatically smooth riding while aluminum is harsh. There are stiff, uncomfortable carbon frames out there. It depends a lot on how the bike is built (geometry, tubing profiles, etc) and not completely on material choice. I haven't ridden a carbon DH bike, but I'd imagine that vibration damping and vertical flex would be pretty low on the list of things that were designed into the frame, though carbon may have some degree of each naturally.

 

[Tdubb]

Heres a tease I just got sent to me.

 

[Freddy Salgado]

This thread is very heavy with inaccurate and mis-informed statements.

It's not even worth addressing them- but any material can be good or bad for building bikes, and carbon is certainly the best if you take ease of manufacture and simplicity of design out of the equation. Come on people, I know we are cynical here on Ridemonkey, but SantaCruz and their manufacturing partners are top-fricking notch.

Carbon is the best material for DH application

 

[Freddy Salgado]

Those Lahars are legendary, here they been handed around so many people second hand its like Stifflers mom, keeps coming back 4 more and still takes a beating, pity it went the way it did, could have been like similar to biking like what the Britten did the the big 4 at Daytona back in the day, now that was and still is a bike, and a dude as well plus one hell of an engineer

I have said this before, Aaron's rig should be on display at Te Papa museum next to Britten's. Both are great examples of Kiwi icons way ahead of there time! Carbon revolution cemented with the roadies, most high end xc rigs are carbon, now its trickling into DH like it or not. I predict bamboo & flax will be the next exotic DH frame materials.