[LMC]

Hi Guys,

I am trying to get a feel for scepticism about certain frame materials suitability for DH. Especially in light of the session 88 that snapped last weekend at the WC.

So with weight and price for each frame being the same, (so steel would have the thinnest tubes, followed by alu and then carbon fibre having the thickest tubes and being strongest on paper by far)

what frame material do you prefer?

 

[jonKranked]

Steel is real.

 

[IH8Rice]

Hi Guys,

I am trying to get a feel for scepticism about certain frame materials suitability for DH. Especially in light of the session 88 that snapped last weekend at the WC.

youre right, that would have never happened w/ a steel or CF bike

 

[LMC]

like i said just trying to get peoples opinions.. and there was a bit of a fuss kicked up about that incident, and about uber thin alu tubes being unsuitable etc. thats why i mentioned it.

 

[wood booger]

Carbon has the most design freedom in terms of a frame material. It is also the most expensive to produce because it usually has very high initial tooling costs if you want to get the most from the material.

All 3 are more than capable, it just depends on what you are trying to accomplish. Weight, stiffness, impact stength, etc.

I don't see how you could have the same weight (or cost) for all three w/o drastically different frame chasteristics.

How many steel DH bikes are running around these days? 10-15 years ago maybe, but not now.

As a material Al is very cheap and pretty light.

 

[LMC]

I don't see how you could have the same weight (or cost) for all three w/o drastically different frame chasteristics.

.

you are right, but im only interested in strength/durability so i levelled the playing field with price and weight.

 

[Gridds]

Say no to crack - ride steel!!

But carbon, done right, is the future!

 

[Eastern States Cup]

umm True Temper Supertherm double butted 4130 (steel)tubing if you can get it (doubtful). weight and strength perfection.

Price, well you would not believe !!!!

 

[norbar]

Carbon all the way. If it could be done right it would be great. Hope the fury will work and finaly start a new trend.

 

[LMC]

umm True Temper Supertherm double butted 4130 (steel)tubing if you can get it (doubtful). weight and strength perfection.

Price, well you would not believe !!!!

you can buy tubesets from henryjames.com they have some prices up too, and yes its good value for the material.

 

[LMC]

Carbon all the way. If it could be done right it would be great. Hope the fury will work and finaly start a new trend.

im with you on that one. the fury looks stunning and should turn out to be bombproof

 

[RD3]

Any of the 3 are great in their own ways, just depends on the goals of the overall design and how close you push the edge of getting it both light weight and durable.

 

[norbar]

im with you on that one. the fury looks stunning and should turn out to be bombproof

I'm all the way behind that project but still bombproof and a gt downhill bike in once sentence seems very ironic for me

 

[Ksquaredracing]

So with weight and price for each frame being the same, (so steel would have the thinnest tubes, followed by alu and then carbon fibre having the thickest tubes and being strongest on paper by far)

I understand what you are trying to get at but I think eliminating the weight and cost of a material reduces this to an academic point of which materials properties are better suited to DH. For that you could just go get the specifications on the material and it wouldn't make any difference which matterial won a poll.

Any matterial used incorreclty will have problems. I know of a carbonfiber swingarm on a motorcycle that snapped mid corner on a race track, I've seen steel that fatiged to the point of cracking, and I've seen aluminum bend and deform. The right material is the one that can be built light, strong, and at the right price.

I would like my next bike to be built from pure unobtainium.

 

[no skid marks]

Aluminum is used over steel because complex shapes can be made, and it's cheaper, it also generally won't last as long, so the customer will need to buy again.
Carbon is the best, bust it can be done so very wrong, but so can welding, tube choice, and design. The thing with carbon is a lot of money needs to be paid to make it work. In such a marketing driven(and design evolution to a point)market, where new frame hype sells bikes, the advantage of carbon is outweighed for profitability.
The big brands are starting to ease into it, then hopefully it will snow ball.
I'd like to see steel used more as it's not as hazardous or environmentally taxing.

 

[LMC]

I understand what you are trying to get at but I think eliminating the weight and cost of a material reduces this to an academic point of which materials properties are better suited to DH. For that you could just go get the specifications on the material and it wouldn't make any difference which matterial won a poll.

i know the specs on each material, on paper carbon fibre is the obvious choice, but that doesnt always correlate with public opinion, and its purely peoples confidence in different frame materials that im trying to ascertain.

 

[Eastern States Cup]

you can buy tubesets from henryjames.com they have some prices up too, and yes its good value for the material.

sorry but I don't see anything about supertherm on that site. Maybe I 've had a few too many tonite. From the explanation I got it actually gets stronger from the welding heat. And it's pretty hard to obtain.



"SUPERTHERM ™ is made from a proprietary superthermophilic (heat-loving) alloy. With an industry-leading strength of 217 KSI. These tubes will take a thrashing and come back for more. This is the ultimate material for high strength and low weight so you can go higher, faster, longer."

 

[LMC]

sorry but I don't see anything about supertherm on that site. Maybe I 've had a few too many tonite. From the explanation I got it actually gets stronger from the welding heat. And it's pretty hard to obtain.



"SUPERTHERM ™ is made from a proprietary superthermophilic (heat-loving) alloy. With an industry-leading strength of 217 KSI. These tubes will take a thrashing and come back for more. This is the ultimate material for high strength and low weight so you can go higher, faster, longer."

sorry, youre right. I was confusing it with the other true temper tubesets.. OX platinum etc

 

[Ksquaredracing]

its purely peoples confidence in different frame materials that im trying to ascertain.

That makes more sense to me with this expenation. This isn't what came across to me either in the pole question or the clarification of it in the first post.

 

[slowmtb]

From an early age I have been around people who have or have worked with carbon fibre and believe it is the future. The problem with it is that in its infancy carbon fibre was occasionally used incorrectly resulting in catastrophic failures, and unfortunately some of these failures were very public ( F1, Moto GP etc ) and as a result the average Joe is wary of it.

One of the applications was the extensive use of it in the "Britten" ( a New Zealand made V twin road racer ), this machine was / is still a very revolutionary machine and set the world on fire. Initially the girder fork was incorrectly engineered and failed causing an accident which became very public over here ( NZ ). A redesign fixed the problem ( basically it was engineered too rigid and as a result proved to be brittle, engineered flex solved the problem ).

Anyway to cut a long story short, engineered correctly it is an extremely capable, practical, flexible ( from a design point of view ) material to work with and is capable of withstanding a high stress environment ( impact and tortionally ).

An XC racer over here had an unfortunate incident were as a fellow competitors bike fell on his frame and punctured a hole straight through it ( handle bar was not plugged ). This happened just before the 6 hour event and he had no spare. The decision was made to race it regardless, he finished the whole race and placed on the podium, I am sure an Alloy frame would not have lasted without cracking apart. The carbon frame did not show any signs of further damage.

Carbon FTW

 

[DHRracer]

sorry but I don't see anything about supertherm on that site. Maybe I 've had a few too many tonite. From the explanation I got it actually gets stronger from the welding heat. And it's pretty hard to obtain.



"SUPERTHERM ™ is made from a proprietary superthermophilic (heat-loving) alloy. With an industry-leading strength of 217 KSI. These tubes will take a thrashing and come back for more. This is the ultimate material for high strength and low weight so you can go higher, faster, longer."

You say industry-leading,what industry.Are you familiar with Aermet 310 and Aremet 340?I believe the manufacture makes tubes out of 310 not sure of 340.Each number referes to its KSI when heat treated properly.Just because a material has a high strength to weight ratio does not mean its a good choice.Factors such as cost,weldability,machineability and of course modulus all will play a role material choice.

 

[Iridemtb]

From an early age I have been around people who have or have worked with carbon fibre and believe it is the future. The problem with it is that in its infancy carbon fibre was occasionally used incorrectly resulting in catastrophic failures, and unfortunately some of these failures were very public ( F1, Moto GP etc ) and as a result the average Joe is wary of it.

One of the applications was the extensive use of it in the "Britten" ( a New Zealand made V twin road racer ), this machine was / is still a very revolutionary machine and set the world on fire. Initially the girder fork was incorrectly engineered and failed causing an accident which became very public over here ( NZ ). A redesign fixed the problem ( basically it was engineered too rigid and as a result proved to be brittle, engineered flex solved the problem ).

Anyway to cut a long story short, engineered correctly it is an extremely capable, practical, flexible ( from a design point of view ) material to work with and is capable of withstanding a high stress environment ( impact and tortionally ).

An XC racer over here had an unfortunate incident were as a fellow competitors bike fell on his frame and punctured a hole straight through it ( handle bar was not plugged ). This happened just before the 6 hour event and he had no spare. The decision was made to race it regardless, he finished the whole race and placed on the podium, I am sure an Alloy frame would not have lasted without cracking apart. The carbon frame did not show any signs of further damage.

Carbon FTW

Carbon can be made to use. But how many times do we poke holes in alloy frames? Anyways...

 

[Sandwich]

I am sure an Alloy frame would not have lasted without cracking apart.

based on what?

If weight is purely the concern, aluminum. If I'm buying the frame for myself, I'd lean towards steel. Materials and craftsmanship keep getting better (making bikes lighter), and even still, the extra pound of frame weight wouldn't be as noticeable as, say, heavy wheels or a fork or similar. Steel is more resilient and can be repaired easily, in addition. Aluminum can simply be manipulated easier and is usually lighter.

Carbon...eh. So much potential, so much of it wasted. GT, Trek, BCD, Lahar, nobody has seemed to be able to really make it work. Maybe that will change in the future. It certainly has possibilities, but steel is a better investment, when you're shelling out 3gs on a frame.

 

[Eastern States Cup]

You say industry-leading,what industry.Are you familiar with Aermet 310 and Aremet 340?I believe the manufacture makes tubes out of 310 not sure of 340.Each number referes to its KSI when heat treated properly.Just because a material has a high strength to weight ratio does not mean its a good choice.Factors such as cost,weldability,machineability and of course modulus all will play a role material choice.

easy puppy, notice the quotes. Cut and pasted from true tempers site. I really know nothing except it is used on Superco's Silencer. It was welded into a superior DH frame and my son said it was awsome and light. So what bike was made of these tubes that your not sure are even made.

Maybe your post is not relevant to the original poster. Mine was.

 

[ohio]

You say industry-leading,what industry.Are you familiar with Aermet 310 and Aremet 340?I believe the manufacture makes tubes out of 310 not sure of 340.Each number referes to its KSI when heat treated properly.Just because a material has a high strength to weight ratio does not mean its a good choice.Factors such as cost,weldability,machineability and of course modulus all will play a role material choice.

Dude, it's a cut and paste marketing blurb but it is definitely at the upper end for non-aerospace/defense tubing. Aermet 100 runs about $100 a foot for the straight gauge shizzy and is hard as **** to weld at thicknesses that make sense for bicycles. I don't even know if anyone has or can butt it. There's like 5 small builders using it and because of the limitations it's currently more of a novelty than anything that could be called industry-leading.

The other aermets belong in the same category as beryllium.

Supertherm is up there with top-end offerings from Reynolds and Dedacciai... they're all within a few ksi of each other, and it comes down to who makes the most appropriate tube profile for your application and will sell it to you in small enough quantities for a DH bike.

 

[LMC]

That makes more sense to me with this expenation. This isn't what came across to me either in the pole question or the clarification of it in the first post.

apologies for the confusion..

and thanks to everyone for the feedback so far

 

[DHRracer]

easy puppy, notice the quotes. Cut and pasted from true tempers site. I really know nothing except it is used on Superco's Silencer. It was welded into a superior DH frame and my son said it was awsome and light. So what bike was made of these tubes that your not sure are even made.

Maybe your post is not relevant to the original poster. Mine was.

Did'nt mean to offend anybody.I was just trying to make the point that there are a lot of things to consider when making a choice on material.A materials ksi. is just one of them.