Steel back in the peleton...

[udxcob]

So cool

[gummibear]

I guess everything is relative. If you are looking for a comfortable bike for hours in the saddle, steel probably has its place - Ti too for that matter. I know how you feel about the lively feel (note many steel frames in previous post). This is a subjective thing though. I think you will find however, while they don't have the 'real' steel feel, the carbon and ali frames will actually give more acceleration even though you might perceive them otherwise.

 

The other effect that I perceive in a similar way to this is the 'rubber band' effect of turbo cars that make them feel faster than similar powered normally aspirated cars. In this case you stamp on the frame and like an elastic band it springs back at you - it feels great, but what you have actually done is expended energy deflecting the frame, regained most on the springs back but wasted a little in the process.

 

Despite the OP stating steel is back in the peleton, look up the Condor bike in question - frame weight 1800g for a 52cm frame. The other popular top end steel 953 e.g. Madison Genesis Volare, can get you down to 1600g for a similar size frame. At the top end of the sport, hauling an extra half kilo plus up hill isn't going to happen when a big race victory is on the cards. The condor in question weighs 7.2kg with everything else around the frame in...... you got it - carbon firbre! Incl super light climbing wheels it is still nearly half a kilo over the UCI weigh limit

 

Baum has become very big in Europe and they building 1200g frames with Enve forks.That's lighter than many carbon frames including the Dogma.Seen many bikes in the 6.5-6.8kg range with Lightweight wheels.

[Eldron]

 

 

Baum has become very big in Europe and they building 1200g frames with Enve forks.That's lighter than many carbon frames including the Dogma.Seen many bikes in the 6.5-6.8kg range with Lightweight wheels.

 

Top end carbon frames are closer to 850g so the Baum is still 30% heavier. That isn't really the problem though - carbon frames can use multiple carbon sheets in multi directional lays in almost infinite tube shapes to create the right properties in the right areas.

 

Steel simply cannot match carbon as a race oriented frame material.

 

Desirable, beautiful, handmade, artistic, comfortable, low tech barrier to entry, built by 1 expert in his shed - steel is all of those things but not for racing.

[GoLefty!!]

There is not much that a fancy shape tube can do that a round tube can't.

 

 

 

For interest, use it don't use it. MXS-R or Slick 360/540 or Corvus racer 540 vs Edge 540.

 

The former are all composite aerobatic aircraft. The Zivko Aviation Edge 540 is a steel space frame fuselage with composite wings. The Edge 540 has dominated the RedBull Airrace since inception and remains the aircraft of choice for the return of RBAR in 2014.

Edited December 17, 2013 by GoLefty!!

[greatwhite]

There is not much that a fancy shape tube can do that a round tube can't.

 

 

 

For interest, use it don't use it. MXS-R or Slick 360/540 or Corvus racer 540 vs Edge 540.

 

The former are all composite aerobatic aircraft. The Zivko Aviation Edge 540 is a steel space frame fuselage with composite wings. The Edge 540 has dominated the RedBull Airrace since inception and remains the aircraft of choice for the return of RBAR in 2014.

 

Changing section of a tube along its length to deal with variable stresses is a whole lot better when your not just stuck to round (and constant diameter along length).

 

As for aircraft - Airbus and Boeing invest heavily in carbon and other composites. As do all the major military aircraft builders. I suspect the limits for the aircraft to which you refer are budgetary constraints and/or ease of repair. although, I must concede, that I know a great deal about racing aricraft.

[GoLefty!!]

I think you need to go and do the calculations of the variable shape tubes vs round tubes. The major dimension that impacts the structure is the distance from the neutral axis the material is placed. Funny shapes only try to optimise very slightly what is already an impressively stiff and compliant structure that is the bicycle frame. The same can be achieved through round tubes.

 

The Zivko Edge 540 uses round steel tubes, similar to Reynolds 531 for its structure. Yes it was chosen for repairability and longevity of the airframe but it is more than stiff enough to achieve a excess of 12 G LOADING POSITIVE AND NEGATIVE, A 420 degree per second roll rate without the wings falling off of the fuselage falling apart. If steel is good enough for this competition airframe through which massive forces are placed, I think its more than strong enough for a bicycle frame and can be built light enough.

 

Yes Boeing and Lockheed Martin use carbon composites in the airframes, sometimes to reduce weight but mostly in military applications to reduce the radar cross section of an airplane. Weight is also a consideration ie. carbon fibre body panels are lighter than steel body panels since the steel has to be a minimum thickness to ensure the panels does not distort when fasteners are applied. A lot of composites are use in non essential or non structural elements to reduce weight since Carbon main spars are expensive and offer very little weight saving. The F22 uses a carbon main spar but mostly because the design has too allow for internal weapons bays which makes the main spar a complex shape. Producing this in aluminium would be have too time consuming and hence expensive wheres moulding from carbon achieved the weight and strength targets.

The humble bicycle has more in common with the smaller aerobatic airplanes. Bicycles are not complex. We're just told they are so we can be suckered into paying more for less

 

The only reason we don't see steel in the pro peleton is because it does not sell bikes. Carbon fibre is "Space age" .

[Christie]

 

Steel simply cannot match carbon as a race oriented frame material.

 

Desirable, beautiful, handmade, artistic, comfortable, low tech barrier to entry, built by 1 expert in his shed - steel is all of those things but not for racing.

Agreed, well said.

 

Something to mention is that steel and alu beats carbon in the joints, though. Carbon tubes are vastly superior to the equivalent metal ones for the same shape, but carbon joints are ineffecient, because material has to be overlapped to join them. That is the reason carbon frames do not weigh 1/4 of a steel frame. A metal weld is much more efficient when done right. The effect would be bigger on small sized structures, where the weight of the joints make up a bigger % of the total. This is why the best metal stems and cranks weigh the same as carbon ones. But people buy those components in carbon because marketers tell them to.

 

[rouxtjie]

Agreed, well said.

 

Something to mention is that steel and alu beats carbon in the joints, though. Carbon tubes are vastly superior to the equivalent metal ones for the same shape, but carbon joints are ineffecient, because material has to be overlapped to join them. That is the reason carbon frames do not weigh 1/4 of a steel frame. A metal weld is much more efficient when done right. The effect would be bigger on small sized structures, where the weight of the joints make up a bigger % of the total. This is why the best metal stems and cranks weigh the same as carbon ones. But people buy those components in carbon because marketers tell them to.

Relative

[Hairy]

I don't know hey.....Would be great to see steel making a big comeback on frame construction.

 

All we need is a company to release a new wonder steel tube and the cycle world can get all excited about it.

 

Steel is also a better material to recycle should the frame be horribly broken.

[rouxtjie]

I don't know hey.....Would be great to see steel making a big comeback on frame construction.

 

All we need is a company to release a new wonder steel tube and the cycle world can get all excited about it.

 

Steel is also a better material to recycle should the frame be horribly broken.

ja, give it a cool lightweight name like farkolaminium, let the big roadbike manufacturers give it to their tour riders...

 

Boom...winner winner

[GoLefty!!]

Top end carbon frames are closer to 850g so the Baum is still 30% heavier. That isn't really the problem though - carbon frames can use multiple carbon sheets in multi directional lays in almost infinite tube shapes to create the right properties in the right areas.

 

Steel simply cannot match carbon as a race oriented frame material.

 

Desirable, beautiful, handmade, artistic, comfortable, low tech barrier to entry, built by 1 expert in his shed - steel is all of those things but not for racing.

 

 

can you provide technical reasoning to your arguement "Steel simply cannot match carbon as a race oriented frame material".

[Eldron]

can you provide technical reasoning to your arguement "Steel simply cannot match carbon as a race oriented frame material".

 

I must be having a deja vu moment - I'm sure we've had at it already in this thread.

 

One disclaimer though - when I say "race oriented" I mean the "standard" 100km road/70km mtb race/tours etc. I have already agreed with you on the Paris Roubaix idea. I'll take it a step further and say that my material of choice for 6, 12 and 24 hour mtb racing had always been round, small gauge steel where the advantage of comfort outdoes the weight advantage.

[GoLefty!!]

Its not de ja vu.... what makes that very narrow description of a race worthy of being suitable for a carbon frame?

[greatwhite]

Its not de ja vu.... what makes that very narrow description of a race worthy of being suitable for a carbon frame?

 

I think the description was perhaps narrow. I would say best for the largest portion of racing by both type and participation.

 

200km on cobbles and 24 hour mtb are the exception not the rule

[greatwhite]

Agreed, well said.

 

Something to mention is that steel and alu beats carbon in the joints, though. Carbon tubes are vastly superior to the equivalent metal ones for the same shape, but carbon joints are ineffecient, because material has to be overlapped to join them. That is the reason carbon frames do not weigh 1/4 of a steel frame. A metal weld is much more efficient when done right. The effect would be bigger on small sized structures, where the weight of the joints make up a bigger % of the total. This is why the best metal stems and cranks weigh the same as carbon ones. But people buy those components in carbon because marketers tell them to.

 

valid point and and especially relating to stems, I agree. Bars are nice and straight though and lend themselves to carbon fibre.

 

The right material in the right place is what it is about for me. I just feel most race frames benefit from carbon. I even have misgivings about steel being best for cobbles or 24he solo racing , but since I have no experience there so I'll concede it (has anyone on this thread done either?)

[greatwhite]

I think you need to go and do the calculations of the variable shape tubes vs round tubes. The major dimension that impacts the structure is the distance from the neutral axis the material is placed. Funny shapes only try to optimise very slightly what is already an impressively stiff and compliant structure that is the bicycle frame. The same can be achieved through round tubes.

 

I think you misunderstand me - I agree, if I had a square tube or round tube that had the same mass per meter and same wall thickness and it was constant diameter all the way there would be little in it in terms of stiffness (lets ignore buckling issues - the round tube wins there no question).

 

If you are able to place the material further from the neutral axis, is would be stiffer - Agreed? (You have implied as much already) - In the late '80s, early '90s the likes of Columbus reached that conclusion and made products like 'MAX' which was elliptical to get the extra distance in the axis that required it, but it was still round tubes that had been made progressively more elliptical as it approached its ends. They were also butted which helped in the high stress areas.

 

Now imagine making any shape you want with steel - as an example, imagine you could make the down tube grow in diameter from Ø34.9 where the Front derailleur clamps to say 60mm wide x 40mm at the BB shell and you could thin down the material without it buckling so you get maximum weight saving and the desired lateral rigidity.

 

That's what I meant about changing section - not making it round or square.

 

Problem is, making special highly variable sections with steel - especially super high strength alloys, it is difficult. And even if you could/did, to get the mass down, the wall thicknesses would be so thin, you would be dealing with buckling issues. Even with the same strength to mass ratio, this is all viable carbon fibre due to lower density(read thicker walls and reduced buckling) and the relatively easy shaping process. Now factor in the higher strength to mass ratio and better elastic modulus of good carbon fibre.....

 

 

The humble bicycle has more in common with the smaller aerobatic airplanes. Bicycles are not complex. We're just told they are so we can be suckered into paying more for less

 

The only reason we don't see steel in the pro peleton is because it does not sell bikes. Carbon fibre is "Space age" .

 

I agree, bicycles are not complex, which is, imo, one of the reasons we see carbon used so often - its easy to implement. It does bother me when I see frame advertising with FEA and CFD that on a few second inspection is rubbish - you won't see too much of that on a steel frame advert.

 

As for the reason we don't see it in the peleton often - it doesn't win races. If it wins races it sells more. The other reason is the easiest measurable - mass. Its hard to sell a frame that weighs 50% more (going on Gummibears comment of a 1.2kg frame - though I could not substantiate it being that light) for the same money - which relates back to the reason it doesn't win races - too heavy!

Edited December 23, 2013 by greatwhite