En esta entrada voy a analizar a la nueva Marin Wolf Ridge 2018, un modelo Enduro con 160mm de recorrido y ruedas de 29'' en el que Marin estrena un nuevo sistema de suspensión diseñado por Darrel Voss. El basculante trasero incorpora un tubo telescópico y se conecta al triangulo trasero mediante una bieleta, creando un sistema de Pivote Virtual muy novedoso. Aprovechando la confusión Marin aprovecha para lanzar un par de eslóganes bastante llamativos, pero al final el funcionamiento real acaba dependiendo de la cinemática y del amortiguador, exactamente igual que cualquier otro modelo, cada uno con sus ventajas y sus inconvenientes...
Como podéis ver en la tabla de excel y en las gráficas anteriores el sistema de la Marin Wolf Ridge tiene una Eficacia de Pedaleo muy alta, con unos porcentajes de Anti-squat muy elevados (150%-100%). A esto hay que sumarle una gráfica de AS con pendiente ascendente, por lo que el sistema se mantiene siempre por encima del 100% de Anti-squat, independientemente del porcentaje de Sag (20%-25%-30%-35%...) y del terreno por el que estemos circulando. Como ya os podéis imaginar el sistema tiene un Pedal-kickback muy elevado (28º), unas cifras de record dentro de esta categoría que van a generar muchos problemas en zonas de subida técnica. En la presentación oficial Marin comentó que un sistema tan efectivo puede funcionar prácticamente sin hidráulico en compresión y en parte tienen razón, pero cuando el PK es tan elevado perdemos toda la sensibilidad que se había ganado al reducir el hidráulico (LSC). En cuanto al comportamiento en frenada, el sistema tiene un porcentaje de Brake-squat (65%) bastante bajo, no llega al nivel de un FSR pero es una cifra bastante buena para un sistema de Pivote Virtual.
En la gráfica del Leverage Ratio vemos como el sistema es del tipo progresivo (3.25-2.55). El sistema tiene una progresividad media que se mantiene a lo largo de todo el recorrido y por lo tanto se adapta muy bien a todo tipo de amortiguadores, tanto de aire como de muelle. La única critica que se le puede hacer es que el LRM está un poco por encima de la media (2.8:1), ya que este modelo viene equipado con un amortiguador Fox Float X2 de 200x57mm, un gran amortiguador, pero con una medida antigua (no es Metric...) y algo pequeña.
En la gráfica del Leverage Ratio vemos como el sistema es del tipo progresivo (3.25-2.55). El sistema tiene una progresividad media que se mantiene a lo largo de todo el recorrido y por lo tanto se adapta muy bien a todo tipo de amortiguadores, tanto de aire como de muelle. La única critica que se le puede hacer es que el LRM está un poco por encima de la media (2.8:1), ya que este modelo viene equipado con un amortiguador Fox Float X2 de 200x57mm, un gran amortiguador, pero con una medida antigua (no es Metric...) y algo pequeña.
Un saludo.
15 comentarios:
Este artefacto va a durar menos en el mercdo, que un caramelo a la puerta de un colegio.
Saludos.
Es un producto de primer año y se han equivocado un poco con el Marketing... Ahora todo depende de las marcas, si se lo toman en serio y empiezan a pulir detalles a lo mejor pueden llegar a algun sitio, si se relajan y se creen que ya lo tienen todo hecho pasarán sin pena ni gloria.
Un saludo.
How do you explain the big difference riders feel between this design and others? From the kinematic it is very middle of the road, nothing spectacular, but multiple respected sources have claimed that it rides very different from other bikes. Do you think the reviewers are imagining things or is it possible there is something else going on? I have never ridden it and have no stake in the matter, I'm just trying to reconcile these figures with the subjective performance people have talked about.
I think the best review of this bike is the one at Bikeradar. If you haven't see it, doit now... https://www.youtube.com/watch?v=yxJWjt3RTlM
They are the only ones that have noticed the problem with the High Pedal-Kickback (28º is not middle of the road), and also that going crazy with so very little damping is not that great when you start going fast. I really don't care about stiffness, weight or geometry, some of the reviews complain about that stuff a bit but in general you can tell that the designer talks a lot and the journalist don't know how to react, they only repeat what the designer says.
Best regards,
Tony.
Solo me faltaba por ver el video.
Esta bici esta a media cocción, y va a ser carne de mercadillo de segunda mano, en pocos meses.
La flexión de la trasera es inadmisible.
Saludos.
The video link has disappeared on Bike Radar. I wonder if Yeti is doing some damage control on a bike they rushed to market, and have obviously made some grave errors in implementation of frame,both in terms of weight,geometry and kinematics. It appears to be a poor substitute for a SB4.5 with its only advantage of a water bottle in the frame.
Disclaimer: I'm part of the development of this bike. The actual pedal kickback as it relates to the kinematic cannot be determined by Bikechecker, there are other forces at work here. Let's just say that determining the ride of some more unusual IC paths and rates cannot be easily determined by looking at these usual graphs. I agree that much can be known while sitting at a desk, and indeed many suspension designs begin in this manner. Yet in the case of the R3act 2-Play suspension in particular, there are many forces at work that have been purposely applied in this design that previously all other designs have not let alone been isolated. For anyone to think that just the forces listed there are usually used to analyze a suspension is all there are to the possibility of advancing suspension is a mistake. There is alot more significant forces going on than all but a few suspension designers can apply. In the case of the R3act 2-Play and why it's different is because there have been engineered physics purposely applied that have never been before. The bottom line is of course riding the bike.
What is not mentioned in this post is that the shock tune is on average 70% lower damping rate that any other bike on the market. Damping is restriction and restriction is efficiency loss. Fox cannot even de-tune their shocks low enough by inherent design. Meaning that the Wolf Ridge needs a shock that can run low pressures that most shocks are not designed to do.
That every other suspension design on the market requires higher overall damping in general is significant. This allows the Wolf Ridge to track the ground and the rear tire not having to be more heavily restricted. Better traction, more use of the travel since it does not have to sit in the travel as much to compensate for more restriction. And this does not even get into the higher pedaling efficiency that results and much higher pedaling isolation when climbing. A 160 travel bike that climbs like a 100 travel bike. Again riding it is better than trying to determine by these graphs when there are many more forces that Bikechecker cannot show. I'm not that knowlegable on most kinematic theory for mountain bike suspension, yet I do know this suspension rides better than any other and I've ridden quite a few bikes both shorter and long term. This site is very useful for getting a general idea of bikes, yet in this case of the Wolf Ridge there is more purposely engineered forces than what can be known here. This I know.
The last version of the program can work with sliders without any problems, and the calculation of the Pedal kickback looks fine to me. If you design a bike with high Anti-squat around sag and a flat or rising AS curve you are going to have a lot of Pedal Kickback, that's something completely normal and inavoidable.
The only force the program can't calculate is the friction of the slider as Zubi said in the Polygon Xquare article, and if that's what makes the system works, it would be pretty sad.
Best regards,
Tony.
There is some hostility to this bike because it is not easy to understand. If everything about mountain bike suspension is understood now, then that would be sad. Yet anyone who actually rides this bike will realize that there is indeed still much to be learned and improved. We can all be excited that significant advances in suspension kinematics are possible.
Nope, this is just another example where someone creates a new system and then try to take advantage of the initial confusion to claim that it works better than anything else on the market "because reasons".
Polygon has published AS and AR curves of the system and I got exactly the same results using the Linkage program. I'm 100% sure that Pedal-Kickback and Leverage Ratio curves are right too, and that's all that matters.
You can go as low as you want with the compression damping, that's going to have pros and cons, but any other brand with similar kinematics can do the same.
Best regards,
Tony.
You said: “I'm 100% sure that Pedal-Kickback and Leverage Ratio curves are right too, and that's all that matters.”
I’ll leave it at that. I do appreciate your time to comment.
Joe
Kinematics = [AP,AS,AR,PK,LR]
And by the way, I didn't use the geometry drawing of the
Polygon, I noticed that it was manipulated and did it using other resources...
Best regards,
Tony.
Hola Antonio...cómo estás?? Te escribo desde Argentina.. digo tú blog. Me encanta!! Pero quería consultarte una cosa. Cuando vos hablas de baja eficiencia de pedaleo pero de buena eficiencia en subidas técnicas.. cuál es la diferencia? A q llamas subidas técnicas?? Con piedras o mucha pendiente? Gracias y un abrazo grande
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