Specialized Demo 2015

En esta entrada voy a analizar a la nueva Specialized Demo 2015, un cuadro que a simple vista parece completamente distinto, pero que sorprendentemente tiene un funcionamiento casi idéntico al de la versión anterior. Estamos ante un caso parecido al de la Commencal Supreme en los años 2010-2011, Scott Gambler en 2012-2013, GT Fury en 2013-2014, Pivot Phoenix 2014-2015... Cambio radical en el diseño y estética completamente renovada, pero con muy pocos cambios en la cinemática...
Como podéis ver en la tabla de excel y en las primeras gráficas el sistema de la nueva Specialized Demo 2015 tiene una Eficacia de pedaleo muy baja independientemente del tipo de transmisión que utilizemos, da igual llevar un 36T-38T con 10v, que un 32T-34T con el nuevo grupo Sram de 7v, porque los porcentajes de Anti-squat van a seguir siendo muy bajos. En este caso Specialized utiliza un Horst Link de mayor tamaño, pero el punto de giro principal es concéntrico al eje de pedalier... una cosa compensa a la otra y al final el resultado es exactamente el mismo que en el modelo anterior, con las dos curvas prácticamente superpuestas. El Pedal-kickback (4º) es mínimo y el Brake-squat (27%) se mantiene en un nivel bajisimo.

En la gráfica del Leverage Ratio vemos como el sistema tiene una progresividad muy suave (2.9-2.55). En este apartado tampoco hay muchos cambios, la nueva configuración del sistema FSR se parece un poco a la de la Specialized Status (3.4-2.6 de LR...), pero como podéis ver el LR de la Demo 2015 no es tan progresivo. El cuadro viene equipado con un amortiguador Ohlins de muelle optimizado especificamente para este modelo (En teoría: LSC muy potente para mejorar la Eficacia de pedaleo y HSC también bastante potente para evitar el Bottom-Out...), por lo que el funcionamiento debería ser bueno, pero todo depende del Ohlins TTX.  

Un saludo.

40 comentarios:

Josep Barberà dijo...

Está claro que Spec prioriza ante todo, el bajo AR y bajo KCBCK.
El resto lo deja en manos de un buen amorto. Y a mi me parece una buena estrategia.

Saludos.

sr lobo dijo...

Buena estrategia en que sentido?? no veo que eso sea una ventaja para el usuario, entiendo que el sistema en si es mas bien malillo respecto a otros, y que suple esas carencias con un super amortiguador....entonces, si quieres poner otro amortiguador, o tener uno de aire...? tienes que mandarlo a tunear?

Para mi un buen sistema de suspension tiene que ir bien por si solo, y no necesitar de un amortiguador concreto para que funciona bien.
salu2

Unknown dijo...

I had previously expressed doubt about the structural design of this bike. Jason Chamberlain the frame designer for the new Demo has recently commented on Vital MTB, "We have discovered that the new rear triangle is actually STIFFER than the old bike, through both controlled lab testing and field testing. This was achieved by oversize tubes, specific carbon layup, the addition of 2 bearings, upsizing of 6 bearings, wider bearing stance at the pivots and the rear square axle. All at reduced weight."

Based on this comment, I think it has to be granted that Specialized has done what is necessary to render this new bike sufficiently stiff for its intended purpose. Still, I think the current design, not the forthcoming one, can be seen as the more structurally elegant design i.e. the structural stiffness follows from the basic design rather than a heavy engineering effort to compensate for structural shortcomings of the design.

I am not convinced that "weight reduction" or "lowering the centre of gravity" of the bike are valid justifications for the switch to the new design either. The main elements of the existing rear end could have easily been reimplemented in carbon with an eye to achieving the same design targets.

Un saludo
Chris

Unknown dijo...

Josep y sr lobo,

I think you both have right on your side. Over a considerable length of time I have come to certain views about the overall lay of the land of MTB suspensions. I think if you want to optimise for either i) best pedaling without incurring a high cost in terms of pedal kickback or ii) lowest kickback without sacrificing good pedaling at SAG you will always choose a dual short link suspension e.g. DW-link, VPP or Yeti Switch for pedaling performance or Mondraker Zero for low kickback. Horst-links just can't equal dual short links when measured by these design goals.

But, horst-link bikes (I think the forthcoming Demo is formally a Lawwill link but it doesn't really matter because it functions very much like the current horst-link bike) do offer very particular and sought after dynamic qualities like low AR (or low-rising AR) that is widely considered to be responsible for good/predictable traction during braking. A bike must play to its design strengths and a cost of producing that low AR curve is a fairly modest and falling AS graph across the travel range. That helps keep pedal kickback low too which comes as an added benefit of optimising for a Demo style braking characteristic. To this extent I am in agreement with Josep.

Still, I think sr lobo is right that you can't just disregard pedaling performance when designing the bike. The AS curves of both the existing and forthcoming Demos are unjustifiably low. Perhaps the Ohlins shock almost saves the Demo from itself but I do not see that as an advantage. Besides, low/modest pedal kickback (albeit not as low as the current or forthcoming Demo) is compatible with a better AS curve. You can get the unique braking characteristics and sufficient AS for neutral pedaling at SAG while only incurring modest pedal kickback (more than a Mondraker but less than the pedaling performance oriented dual short links). For a DH bike it makes a lot of sense to accept a compromise where some pedal kickback gets experienced as a consequence of optimising the pedaling performance. For shorter travel bikes with two or more chainrings you can make sure that the pedal kickback is only experienced in the smaller rings which pretty much obviates the compromise.

Un saludo
Chris

Mi isla de La Palma, vista con otros ojos. dijo...

Vaya con el nivel de personas que aqui rondan :)

Oskar.DH dijo...

La verdad q esteticamente mola un monton mas que la anterior y sobre todo la parte de soporte q es solo de lado izquierdo y poder mover el amorto facilmente, diseño radical que gusta ahora para comprarla personalmente no me gusta el sistema de amortiguacion muy viejo y para mi repito para mi gusto obsoleto, imagina si te llegas a comprar el cuadro o la bike entera de segunda mano y sin el Ohlins TTX adios le pongas lo que le pongas ni un CCDB le va bien si no es solo buscar fotos de cuantos doublebarrel rotos hay en demos, buena bike si solo tiene el TTX, q nefastos los de specialized q sigan vendiendo lo mismo solo reestilazados mas bonitos pero el mismo FSR de hace 2 decadas, lastima empresa yanqui q no evoluciona, la unica pega para mi fe los de S fue el brain y ahora hay mejores cosas q eso, no la compraria ni teniendo dinero de sobra

Oskar.DH dijo...

Se me olvidaba antonio espero leas este comentario y hagas un analisis de la nueva BOS FCV te dejo el link y espero tus respuesta asi como lo hicistes con el analisis de la nueva fox suspension reactive de trek la que desarrollaron con penske, espero la informacion del link sea suficiente, a mi me parecio como la idea de los BRIAN de especialized, pero muy mejorada y dentro de la horquilla tu que dices...

Oskar.DH dijo...

http://www.pinkbike.com/news/bos-fcv-idylle-2015.html

BOS FCV 27.5 FORK

Aparte no entiendo porque usaron mas recorrido 208mm, imagino q fue por la medida de 27.5 de ruedas...

ESPERARE EL ANALISIS SUERTE

Antonio Osuna dijo...

El articulo de Pinkbike me lo lei ayer, pero tampoco deja muy claro como funciona exactamente. Tiene pinta de ser una valvula de inercia, pero no creo que esté pensada para bloquear la suspension sino para activar-desactivar un circuito de compresión en alta velocidad???

Sobre la Demo lo que está claro es que es un cuadro muy bonito y a la hora de la verdad la mayoría de la gente se guia por eso, asi que seguramente se venderán muy bien...

Un saludo.

Juan Pablo Pérez guerrero dijo...

Yo creo que sois demasiado perfeccionistas, y esta claro que la bici perfecta no existe,todo depende del uso, y quitando la eficacia de pedaleo esta bici es de lo mejor por no decir lo mejor en todo lo demás, pesó geometría, pedal kidback bajo y brake squash bajo, os recuerdo que es una bici para bajar... Yo si tuviera que quitar algo en una bici de descenso sería la eficacia de pedaleo a ojos cerrados, prefiero tracción y seguridad y en eso pocas ganan ha esta bici,los únicos que podrían achacar esta bici serían los pros, y depende para que circuito,

Juan Pablo Pérez guerrero dijo...

Si fuera una bici de enduro entendería vuestros comentarios, pero para las 2 pedalas que necesitas para coger velocidad en dh, no hace falta tanto, es más Acávo de estar un finde semana en la pinilla, se me rompió el cambio de my súmmum y e estado 2 días sin cadena y sin cambio, y no lo he echado de menos

Juan Pablo Pérez guerrero dijo...

Eficacia de pedaleo en dh? Bagg

Unknown dijo...

Juan,

Okay, the chainless DH bike reference is a salutary reminder about the nature of DH riding. And, I have to admit it is an effective way of drawing attention to what is good about the Demo. Still, DH bikes come with chains and they must. And, it is highly unlikely that riders of chainless DH bikes will be taking home any awards.

I think you gloss over the downside of a heavy reliance on LSC damping by a DH (or other) mountain bike. Using LSC to control unwanted/unacceptable chassis motion (i.e. suspension bob) will normally have a spill over effect. It doesn't just restrict unwanted motions, but also results in an uncompliant/unresponsive suspension which jeopardises rather than aids traction in many riding situations.

Un saludo
Chris

Juan Pablo Pérez guerrero dijo...

Chris,me gustaría poder contestarte en inglés pero no tengo nivel para eso,esta claro que sin cadena no vas a competir...,alo que me refiero sobre my experiencia sin cadena esque bajando casi no pedaleas quitando al salir de ciertas curvas y poco más, ahora bien, creo que nos dejamos ir mucho por los porcentajes, y cuando vemos unos valores tan malos pensamos que la bici no pedalea, y no es asi,yo tengo una Mondraker súmmum de 17 kg, y supuestamente tiene mejor eficacia de pedaleo que la demo, pues bien e tenido el placer de probar una demo de 15 kilos y acelera más que la mía es decir que hay aspectos más importantes que la propia eficacia de pedaleo, y sobre lo del lsc todo depende de la regulación del amortiguador y te vuelvo a decir bajando sólo pedaleas un 10 o un 20 por ciento de la bajada, para que cojones vas a tener el lsc si el otro 80 por ciento necesitas el amortiguador abierto, y te aseguro que las pedaladas que des te van a dar la velocidad que necesitas, y si no pregúntale a troy brosnan el año que viene

Unknown dijo...

Juan,

I respect your position and that of Josep. Everything you have said makes a lot of sense. And I understand your mention of the chainless Summum was purely illustrative. Actually, Josep mentioned a similar experience long ago and it set me wondering (and others too I imagine) about just how serious pedal kickback really was. I have come closer to those I once disagreed with, as a result.

Actually, the idea of a chainless DH bike can be the basis of a good mental experiment. It completely eliminates pedal kickback as a factor affecting a bike's ride so it helps focus other issues without kickback being an additional complicating factor.

So, with that in mind, what would the difference be between dropping a chain on the Summum as against the Demo? Well, the Summum would continue to require more or less the same damper settings as previously - little LSC was required with the chain on because the bike had close to 100% AS at SAG and now with the chain dropped, as squat and anti-squat no longer play any part in the situation, there is still no need for LSC. So, nothing changes and traction stays close to optimal in both cases.

With the Demo the situation is different. All that LSC that was controlling chassis motion, but also impairing suspension compliance/responsiveness, with the chain on, can be wound back to Summum levels (i.e. very little) and traction actually improves after the chain is dropped because there is no longer a need to counteract unwanted chassis motion with LSC as there isn't even the possibility of that chassis motion arising. As it happens, the Ohlins shock is amazing and there will be few people who would want to complain about its performance in the normal (chain on) context. Still, if you could wind back that LSC the bike would ride even better with improved traction, but you can't because all of that LSC is needed to control suspension bob.

I would love to see one of those Ohlins shocks sitting in a Ghost frame. (In my judgement Ghost gets the anti-squat and kickback tradeoff about right on the new Riotlink bike and prototypes. The AR curve is similarly impressive.) That would really be something.

You may be aware that I have attempted to post comments in Spanish previously. By popular demand, I no longer do that.

Un saludo
Chris

Unknown dijo...

The 2015 Demo, like the current 26in bike and the 27.5in revision (already available) will almost certainly be specified with the 30T chainring and 7 speed 9 - 25T cassette that Specialized has used with the Demo for some time. That will make a difference to the AS graph.

Un Saludo
Chris

Unknown dijo...

The idea of a chainless DH bike looks a little less academic today than just a few days ago. Neko Mulally managed fourth at the world champs and he was only 2 seconds slower than the winner! We can reasonably conclude that in the unfortunate situation of losing the chain at least you get the chance to concentrate properly on all aspects of your riding (except pedaling) without the unsettling effect of pedal kickback or the slightest impairment of suspension function from an overly taut chain.

Contrariwise, perhaps we should be wondering how quickly Mulally might have gone if his chain didn't break.

Un Saludo
Chris

Josep Barberà dijo...

Jojojojjoojojo, Chris...

Un comentario/reflexión parecido he realizado al autor del blog, nada mas finalizar la carrera.
Este rider, este dia, ganaba la carrera si o si.

El infortunio hizo que perdiera su cadena en el primer salto, y luego sucedió lo que sabemos todos.
Mi teoria es que el KCBCK afecta sobretodo, cuando damos pedales... Pero también cuando no los damos!.

Interesante lo sucedido ayer...

Saludos.

Antonio Osuna dijo...

La mitad de los favoritos han tenido caidas o problemas asi que yo creo que el podio podría haber sido completamente distinto...

Y si Cris, Pep me mando un Email en pleno directo, sin avisar de Spoilers ni nada XDDD.

Un saludo.

Juan Pablo Pérez guerrero dijo...

Os imagináis las carreras de dh sin transmisión? En vez de pedales estriberas de moto, sólo técnica solo flow

Unknown dijo...

You know me Josep, I don't discount evidence it just takes a lot to convince me. One of the more interesting things about Mulally's race run was how smooth he looked - things looked more in control and perhaps with an extra margin of safety too (credit to Juan for making that point).

It is worth pointing out that, if you have to drop the chain under race conditions, then it would be much better that you drop it riding the Session rather than the Demo because the Session happens to be more pedaling neutral by design so dropping the chain wouldn't result in the same horribly over-damped ride that you would likely get with the Demo viz. the more pedaling neutral Session that naturally relies less on shock damping to achieve geometry stability will typically be ridden with a relatively light shock tune more in keeping with what is required for a chainless descent - a light damping tune that will afford maximum traction for the bike while coasting. Neko Mulally was lucky that his bike happened to be one that would happily continue down the track without a great need to make shock tuning changes. To state the obvious, getting off the bike and making adjustments obviously doesn't work under race conditions.

Okay, I realise that is not really the issue here, though. The point you make (which you have set out here and in many other posts) stands - kickback is the enemy of smoothness and that must have a negative impact on performance.

But can't we hope for a bike that is smooth (little or no kickback), that pedals well and that isn't over-damped? What follows is fairly speculative. Perhaps a high pivoting bike like the Lahar could be an alternative and better source of inspiration for MTB design. (And, maybe there is even a place for a suspension linkage similar to the one on the 2015 Demo in an evolving Lahar inspired design - I've looked at this in simulations and it seems to work well in high pivoting designs and, I think, a good deal better than it does on the forthcoming Demo.)

Un saludo
Chris

Unknown dijo...

Juan,

Yes the rider could have foot pegs and make "vroom" "vroom" sounds all the way down the track.

Cheers
Chris

Juan Pablo Pérez guerrero dijo...

Chris
No me gustan los ruidos... Gracias por las aclaraciones sobre la demo, hoy entiendo algo más de sistemas que hace unos días gracias a ti... Ya que veo que eres muy entendido sobre esto me gustaría hacerte una pregunta, estoy en busca de una nueva bici para enduro y que mejor opinión que la tuya,que bici te comprarías de estas 3, reing, slash o capra

Juan Pablo Pérez guerrero dijo...

Y tu Antonio cual elegirías?

Unknown dijo...

Juan,

The caveat on everything that follows is that you should probably ride the bikes if you can prior to purchase with an eye to how the bikes behave in connection to the things that most matter to you. Also, you wouldn't be too shocked by the news that each of the bikes you mention have their good points. So, let me break things down a little.

First, geometry. The bikes all have good overall geometry but the Capra is somewhat short and sizing up one bike size wouldn't hurt. The bikes are well suited to enduro use and all look like they would be good descending but I think the Slash and Capra benefit from a steeper seat tube angle - Trek doesn't publish effective seat tube angles but I'm pretty sure the angle is on the steeper side, certainly steeper than the Reign - that should help when climbing.

Rear suspension geometry and performance. One way of looking at the effectiveness of a suspension linkage is by weighing the amount of anti-squat it provides - the benefit - against the amount of pedal kickback it imposes - the cost (for a bike that is similarly geared). Looked at from this point of view, the Reign has the edge. It is pedaling neutral using a 32T chainring and pedal kickback is alright. And don't get carried away by the 0.5 degree saving you make by going to the Capra. You need a 28T for a pedaling neutral performance on that bike and when that chainring is used the Capra will exhibit greater pedal kickback than the Reign, by around 2.5 degrees. Being optimised for pedaling in the 32T means that the Reign will adapt well to a broad range of crankset options, and it is the more versatile bike from that point of view. A lot of people who have reviewed these bikes have spoken about how well the Capra rides. I imagine this comes down to the quality and tuning of the BOS suspension components. The LR curves on all three bikes, despite differences, are all good.

Traction. How can this be judged? Well, the truth is, it is guesswork. Still, given the consistent reports of the ride quality and performance of BOS suspension it is reasonable to suppose that the Capra would have the edge in this regard. Looking at the AR curves alone, with an eye to system performance rather than component performance, we might conclude that the Slash would be very good when braking. (note: In lieu of there being a body of undisputed knowledge regarding what an ideal AR curve might look like I have formed the opinion, the opposite of the view I held earlier, that a rising AR curve is probably best. That opinion has some experimental and theoretical support and agrees with the approach used for the vast majority of long beam four bar rear suspension linkages implemented by Specialized, Trek and Dave Weagle on their recent bikes.)

Value. I am not too familiar with European bike prices but I would not dispute the widespread view that the Capra represents very good value for money. An up to date horst-link bike made in light and strong materials with very good geometry (as long as you size up) that is adorned with BOS suspension components and remains affordable. Impressive.

Now, the Capra, complete with BOS suspension, is probably not only the best value bike but also must rate very highly overall. It would be my recommendation. The BOS suspension, though, is the standout feature. If Giant or Trek were to drop their prices for a carbon Reign or Slash down to Capra levels while including the same BOS parts, then a decision between the bikes would be more difficult. Realistically, there is no danger of that happening.

Recommending a bike is not the same thing as evaluating a linkage design. In this particular case the Capra is the best bike, in my view. But the Reign and Slash are not lesser designs only lesser builds. Indeed, I expect that the positioning of the upper link of the rear suspension of the Slash will serve braking traction better than that of the Capra.

Un saludo
Chris

MrBlackmore dijo...

Estoy de acuerdo con Chris, pero tenéis que tener muy en cuenta los fallos de fabricación que está teniendo la Capra (fisuras por varios sitios concretos) :S, aunque parece que van dando soluciones. Otro punto muy importante es el amorto específico de la slash, que si lo quieres cambiar o lo que sea no vas a encontrar de esa medida. Yo personalmente iría sin duda a por la reign, calidad, montajes, muy buena geometría aunque radical, buen precio para no ser de venta directa, buen linkage, lo único mejorable el bs, pero todos los parámetros son muy muy buenos, garantía de por vida, en fin es la que menos pegas tiene bajo mi punto de vista y la que compraría pero con ninguna de las 3 te equivocarás XD

Saludos a todos

Antonio interesantísima la nueva Conway de enduro, a ver que tal va ;)

Antonio Osuna dijo...

Yo estoy fuera del mercado XD y no me tengo que romper la cabeza con estos dilemas, pero las tres bicis que propones tienen un funcionamiento muy bueno asi que al final lo lo que va a decidir la elección son otros factores: Precio, Geometría, Estética, Garantías, Etc...

La Capra tiene una relación calidad-precio muy buena, pero hay mucha gente que no se quiere gastar tanto y por eso la Reign básica y la Strive AL le van a robar mucho mercado. La Trek está muy bien y el amortiguador tampoco es un problema demasiado grande, si tuviese un precio competitivo sería una opción a tener muy en cuenta.

Un saludo.

Juan Pablo Pérez guerrero dijo...

Llevo mucho tiempo con segundas tintas es decir que kiero una tope gama, la reing vale 6200, la slash 5999 y la capra 4000, y la capra es la única que no le cambiaría nada, he estado informándome sobre las fisuras que comentó antes nuestro compañero y no son fisuras si no problemas de pintura y aparte están cambiando todos los basculantes por un mal diseño del anclaje de la patilla de cambio, están respondiendo, no como canyon que no están hablando muy bien xray, asíque para diciembre enero iré a por la capra,gracias a todos por vuestras opiniones

MrBlackmore dijo...

Si, hay un poco de todo, la fisura es entre el anclaje iscg y el cuadro, ya que este es de aluminio y la unión no es buena, que no solo es pintura. Lo de las patillas es otro caso, han cambiado el diseño de la patilla, pero aún así han tenido que rediseñar las vainas. Muy importante el interés que parece que están poniendo en solucionarlo. Yo tengo una Canyon y si, el servicio postventa deja mucho que desear por parte de Canyon España. Buena elección la Capra sin duda ;)

Unknown dijo...

Juan,

You should probably look at this page: http://www.pinkbike.com/forum/listcomments/?threadid=161580

There does seem to be a design issue that is responsible for the cracking at the mating point of the seatstay and the derailleur hanger. Make sure you receive only the most up to date parts, which appear to be free of the problem.

On another matter, I advised sizing up (not so easy if you are a tall rider because Large is the largest bike they have) and I stand by that advice. The Large Capra, for instance, is very close to the size of the Medium Reign and Slash. Sizing up can result in a problem with seat tube length, though, so consider this carefully.

Which brings me to the topic I want to address - stem length. The trend to shorter stems makes a lot of sense if is associated with a corresponding increase in front-centre length e.g. in the manner of Mondraker. A design preference for a shorter stem shouldn't override the requirement for a comfortable riding position, however.

It would be natural to use a longer stem on the Slash or Capra than on the Reign. Despite the very similar wheelbase (and reach) measurements for the bikes (Reign M, Slash M and Capra L) in virtue of its slacker seat tube angle the Reign has a longer Horizontal Top Tube measurement. Being a bit roomier in this dimension means that only a short stem is required for rider comfort. The Slash and Capra, owing to their steeper seat tube angles have shorter HTT measurements. For a rider of the same height a similarly comfortable cockpit on the latter bikes would require the use of a stem that was 15mm - 20mm longer.

Well, if you aren't a Medium rider maybe this is of no interest to you. The point I am trying to make is that you should select a stem based on what is comfortable for you not any doctrine about stem length.

Un saludo
Chris

Juan Pablo Pérez guerrero dijo...

Gracias chris,voy a tener la oportunidad de probarla antes de comprarla, y aunque este decidido ya por la capra también voy a probar la reing,me faltaría la slash y no se porque pero se que si la probara cambiaría de opinión,asíque ya sabéis si alguno tiene una slash que me la deje jejeje, saludos

Unknown dijo...

Antonio,

I wonder if you might consider doing a tutorial on weight distribution, CoG and moments of inertia at some stage. I am not thinking about a formal account of the physics at all but more something that sets out how balance, handling and bicycle composure are affected in different riding situations and with varying degrees of suspension activation depending on where weight happens to be centred. Of special importance would be what happens when weight is added or reduced or moved as occurs when a bike gets a thorough frame redesign.

The comments that follow express my quite limited grasp of these matters.

I don't doubt that small reductions in weight can have a significant effect on bicycle handling but I wonder whether a statement like, "the rear end is lighter and has a lower centre of gravity" (paraphrase only), as has been said about the new Demo, helps or hinders understanding of these matters. First, the statement can only apply to the rear suspension assembly as if it would be sensible to look at it in isolation from the rest of the bike. That is a one-sided way to look at things. The laden bike with rider is really the more important entity that must, if possible, be light and have a low centre of gravity. The overall CoG of bike and rider and the CoG of the rear suspension assembly are not the same thing and while the latter will have an influence on the former there are many other factors involved. Redistributing weight in the rear suspension linkage downward by several centimeters, say, could easily be offset by other distributional changes such as an increase in the mounted height of the shock absorber, which appears to apply in this case. Second, while it is reassuring to think that "reducing the weight" of an assembly and "lowering the CoG" of the assembly (by way of a redesign that anchors suspension parts lower on the chassis) will always cause the same trend - a lowering of the overall CoG, in practice things are more complicated. For a laden bicycle where the rider is elevated on the frame and the densest mass in that system the CoG will be quite high. Reducing weight of components positioned low in the frame can actually increase the height of the CoG (slightly) and thus weight reductions of this sort will tend to partially negate any CoG lowering effect that follows from physically relocating framing/suspension parts to lower chassis positions.

I am not convinced that the CoG that matters (i.e. the CoG of the laden bike) is lower on the 2015 Demo. Perhaps, it doesn't matter so much. There are benefits to the lower weight of the rear end i.e. lower unsprung weight, without having to become preoccupied with the CoG at all.

Un saludo
Chris

Antonio Osuna dijo...

The main problem with this idea is that it's going to be very difficult to experiment and bring some results.

The Dummy in my WM Experiments it's almost a "dead sailor" when going DH. I can program a bit of movement and reactions, but it's never going to be as active as a real rider, and that's when a light bike can make a difference...

Best regards,
Tony.

Juan Pablo Pérez guerrero dijo...

Para los que no creían en esta bicicleta,, ya lo tenéis primera carrera del año y primera victoria para ella

Antonio Osuna dijo...

Tener un equipo de alto nivel es una de las mejores inversiones en publicidad que puede hacer una marca, es algo que está totalmente demostrado, el problema es que las marcas pequeñas no pueden entrar en ese juego.

Un saludo.

Juan Pablo Pérez guerrero dijo...

Si esta claro que el piloto es lo primero.... Pero algunos ponían esta bicicleta tan mal que parecía que no se iba a llevar nada...

Josep Barberà dijo...

A ver qué te parece Antonio.
Muy interesante!:
https://youtu.be/V5UFr-WuS6w

Saludos.

Antonio Osuna dijo...

Yo creo que la idea de hacer el análisis en video está bastante bien, el único fallo es que los modelos no están tan bien hechos como los mios y tienen un poco menos de precisión. El por ejemplo tiene un par de videos de modelos que yo no he hecho todavía (Commencal V4), pero si yo no los hago es porque me faltan datos y el por ir con prisas ha metido la pata hasta el fondo colocando el punto de giro principal concéntrico con la Roldana Idler...

Un saludo.

scott ramson dijo...

Antonio. Cuando puedas analiza la specialized enduro 2017. Que es un cromo a la demo.

Antonio Osuna dijo...

Las imagenes que han salido son un fotomontaje y todavía no hay nada seguro, pero vamos que en cuanto la presenten oficialmente me pongo a trabajar...

Un saludo.

 

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