primero que nada, felicidades!....tu proyecto esta bastante didactico, hasta para un medico como yo que no sabemos mucho de eso. gracias a tu proyecto he logrado entender un poco mas el funcionamiento de la bici. ojala que logres tu objetivo comercial o laboral. felicidades
He solucionado el documento powerpoint de presentación, q antes al descargar daba error y se descargaba otro archivo, ya lo podeis bajar, esta presentacion se explica el proyecto de forma resumida y visual... Todo aquel q kiera dedicar 5 min sin tener q leer e intentar comprender, ahi lo tiene. Gracias a todos por vuestros comentarios, espero que me escribais comentarios en el libro de visitas....
Me he acordado de este mensaje leyendo esto por internet: Creo que es bastante didactico de como puedes llegar a meterte en el mundo de las bicis. Como casi todos los casos de exito, pasion, trabajo, contactos. Veo un diferencial con la mayoria de los que quieren diseñar cuadros en este foro (jovenes ingenieros soñadores...), pero tambien es cierto que los $$$ afectan, este pudo permitirse coches de radiocontrol caros, universidad privada en Boston, mejor mercado laboral que en España... Bastante interesante leer como llego ahi. DW: The bike world now knows you as producing some of the hottest designs on the market for all sorts of riding but bicycle designer extraordinaire is not really a recognised career choice from University, how did you get to where you are now? Dave: OK, wow, this is going to be a long one! Sorry if this turns into a life history, but its the only way I know how to tell it like it really is! For me it was really an evolutionary process starting when I was a little kid. Growing up I was always way into motorcycles, dirt bikes, and really high end RC cars. I used to draw dirt bikes all the time when I was in second grade or so. I bought my first motorcycle magazine subscription with money that I earned from my paper route when I was 8 or 9 years old. Racing R/C cars was like a drug to me growing up. An older guy who lived up the road from me was the best driver and tuner at the R/C tracks in our area. He really taught me how the suspension on my cars worked, and how to tune them. Those were some truly invaluable lessons and I was really lucky to have someone be patient and teach me. I was really into drawing and just creating for as long as I can remember. I spent my free time drawing and dreaming of new things for my RC cars. I built my own suspension for my race car (an RC10 for those of you who know cars) when I was about 12. I don't think it made a difference to the car, but it was a lot of fun to build it and bring it to the track. With high school came muscle cars and lots of time spent working on that. I still raced R/C cars, and I was getting into designing my own parts and modifying the heck out of the cars. Skip a few years, to college. When I was in college, I couldn't afford a dirt bike or mountain bike, I was lucky that I had my old BMX, and I rode that around Boston every day with my friends. I used to ride my bike a lot to blow off steam from classes or when I was pulling all nighters working on the SAE mini baja project. A friend of mine who worked on the baja team had a sweet ti Merlin and was good buddies with the Independent Fabrications guys. At that time I was the guy designing the school's car and overseeing fabrication. I was heavily into analyzing suspension systems using vehicle dynamics equations, and trying to build the most efficient structures and drivelines possible. I got really heavily into vehicle dynamics, composites, etc. around then, I was like a sponge for this stuff. I had aspirations of working for an F1 team. That Merlin and the bikes at IF just amazed me because of the level of manipulation in the materials that they used: butted tubes etc., cool stuff to me. I started to really look into full suspension mountain bikes, I wanted one so bad, but there was no way I could come up with enough money to buy a bike. That might have made me want one more, I'm not sure. I was designing my own CVT for our baja car, and somehow I became somewhat obsessed with designing a CVT transmission for a bike, and I spent a ton of time researching that. I started looking at the bikes and how to apply my new driveline ideas. As I did that, suspensions were there and getting a lot of attention in the magazines, and naturally I wanted to understand those also. Around then I met a beautiful girl (Linley, who I later married), decided that there was no way I was moving to the UK to pursue my F1 dreams, graduated and landed a job at a company designing tactical robotics for the US department of defense. I finally had money and the first thing that I did was buy a bike, a first generation Santa Cruz Superlight with a Z2 BAM and first generation Hayes discs (there were no disc tabs on the frame actually). I started racing downhill and dual slalom immediately and fell in love with the sport. From there I started to get pretty heavy into suspension analysis for bikes. I had some ideas that were just completely radical compared to what existed. I ended up having to basically write my own terminology because the terms that I needed to work with did not exist in any reference that I could find. After a huge amount of work and refinement, these ideas became dw-link. Because of my day job, I was getting into FEA (computer aided structural analysis) and I started to apply that to bicycle frame structures. At this point I had a pretty solid structural and kinematics background going for someone my age, and I guess then the stage was set for me to start building bikes and parts, I just didn't know it at the time. So thats it. Wow, that was comprehensive, but its all out there now! Whew! The Evil Imperial DW: What made the bike industry your choice of career, a love of riding or looking at other designs and feeling you could do better? Dave: It is definitely a bit of both, but realistically, I don't think that love of riding alone could have let me make a career as a competent designer in the bike industry. Based on what I had learned from suspension and structural analysis, I was sure I could build some competitive race bikes. A couple close friends and I started Evil Bikes with that goal in mind. I never really sat down and said "I want to start a bicycle component company and make a career out of it." It's funny, because now, developing new bicycle components is one of the things in life that I enjoy the most. The birth of the component line is an interesting story. When I started racing local DH and slalom (Trail 66 RIP), we were riding in torrential rains every weekend. It was nuts. The tracks were muddy and rocky. Like everyone else, I bought the popular chain guide back then for my bike and set it up. I was psyched; I had a real race bike! That lasted about a day. With the rocks and mud, I destroyed 3 of those damn things in one season. I got so fed up that I designed my own chain retention system from the ground up for my friends and I. My goal was to build not just a guide, but something that could keep the chain on through extreme conditions and still be lightweight. I tried a ton of variations, and eventually, the prototypes used full polycarbonate bashguards. That was unheard of back then. My buddies and I all beat the heck out of these things and we went a whole season without a failure between us. A lot of local riders wanted them, so we decided to build a short run of guides to sell for Evil. From there riders got really fired up on the product, and it sort of snowballed worldwide. I guess that a lot of people were as frustrated as I was, and that cemented in my mind that I could build successful products. DW: Is your work now exclusively in the bicycle industry? Dave: Yeah, most of it is right now. I just don't have time to take on a lot of new outside projects with everything I have going on right now. Plus, I really LOVE what I am doing with bikes, so I don't spend a lot of time looking elsewhere. I've had a few offers to go back to work in the defense community, but so far I haven't bit on those offers. I spend about 15% of my time working on writing patents. I've been burned too many times now, so I really work hard on that. Related to patents, I do have a couple outside things that I have been working on, but those projects are super secret right now. Hopefully in the near future I can break the silence on that stuff. It's pretty exciting. DW: What companies are now benefiting from the DW touch? Dave: I am the president and technical director for e.thirteen components and Evil Bikes, and I work as an outside consultant for Iron Horse Bicycle Company, and Independent Fabrication. Tambien muy interesante es esta aportacion de Dave Weagle en un foro: The Split Pivot bridges the gap between a single pivot and a dw-link. It can do everything that an FSR suspension can do, but it can never have the complex anti squat curve and and performance associated with it that dw-link has. So bottom line with this system, it is a single pivot for acceleration purposes, a multi pivot for braking purposes. In reallity, performance wise it can exactly duplicate what most FSR bikes have done. With a little knowledge (i.e. pivot placement) I think that it can outshine many of the FSR bikes that have been built. The raw idea is that it uses a single pivot location that offers some real benefits for acceleration purposes, but without a floating brake this pivot location that works so well for acceleration would have some real drawbacks under braking. This is where the Split Pivot (the concentric dropout pivot) comes in. The seatstay link and assembly acts as a floating brake arm, exactly like FSR does. Nothing new there at all. The pivot location around the axle is the novelty and why I had to apply for patents etc... Lower cost through an emphasis on wider manufacturing tolerances is one of the biggest advantages of this system. A dw-link needs to be held to tight tolerances to perform as designed. This usually menas CNC machining the entire weldment after heat treat, or pretty careful fixturing and alignment. 1mm is a huge number in dw-link world. A Split Pivot could be welded by a monkey and still probably work out allright. 1mm is practically inconsequential with Split-Pivot. I don't think that Split Pivot could be lighter than dw-link in an ideal world, but it can make a pretty light bike without too much cost. dw-link is structurally pretty hard to beat. Is this bike going to be better than a dw-link bike? Sadly, no. Is it going to ride better than a single pivot or other linkage bikes? I believe completely that it has the ability to. No matter what, Split Pivot can be used to build a pretty light bike with good performace characteristics. There is nothing wrong with that in my book.
