Thanks for this great talk. I hope people in the industry really take your thoughts to heart. You're bringing up important points that few people are talking about. Even as a cyclist who started in the last 2 years, it's plainly obvious that most bike "designers" have no idea how bike geometry affects fit and function. Or they know, but they use marketing to cover up their lazy designs so they can maximize profit. Just look at the how the geometry changes across sizing in one model -- what is fixed and what is changing -- and it should be clear to anyone that the bike will not handle the same across the entire size range. If it doesn't handle similarly, is it really designed for the same purpose? Should it be called the same thing? People at the ends of the size spectrum experience this all the time. We get compromised bikes that feel nothing like what has been advertised. Bike designers need to understand that bikes are an interface between the rider and the terrain. The bike is the link between the rider's contact points (seat, pedals, handles) and the ground contact point (tires). The bike is a tool that enables the rider to travel through the terrain joyfully and safely. It makes the rider feel comfortable and capable. Designers need to stop designing to marketing's specifications, and start thinking about the user and their needs first. It pisses me off enough to consider getting into framebuilding just so I can experiment and discover things that actually work rather than leaving it up to manufacturers and builders who don't seem to care.
I'd push back on the idea that forces normal to the ground should be the ones considered when thinking about fork stanchion flex. When you are going downhill, which is when I'd argue fork performance is most important, I think the forces you care about most are opposite to your direction of movement, which is different than normal to the ground. So while you may get binding in a parking lot with a 63 degree head angle, I think performance could be better on the trail in an enduro context.
Thanks for giving this presentation! Overall I agree that geo charts from manufacturers are largely garbage. And I generally agree with a lot of your bike fit ideas. But I do disagree that head angle and stem length don't matter. At least in my experience, there's a very noticeable change from a 40mm to 50mm stem, and I don't think it's all due to body position differences. I just ordered a 45mm stem to try and will see how that goes. With my ~63.5 static head angle that gets slacker at sag, maybe I'm more sensitive to stem length than you are with steeper head angles.
@@alanbonk3542 I don't believe that the takeaway should be that normal forces are the only ones that matter with stantion bind. I went into great detail about optimization targeting. You can optimize for the 0.1% of a ride where optimizing for extreme downhill performance matters or the 99.9% of the rest of the ride. Or somewhere in between. The point is knowing what you are targeting and why and what costs you will pay for that. There was another hour of lecture that I was forced to cut off where I would have gone into far more detail on this. Also, you should have taken away that you need to focus on grip and wheel location rather than head angle and stem length. Make a print. You will quickly find that I'm correct. If you are doing anything without a print, you are just tossing darts in the dark.
When looking at the geometry of a full suspension frame, doesn't it all change once you weight it with a rider? Presuming the answer is "yes," are the geometries presented accounting for this (like, they assume the average rider of an S4 frame is 180 lbs)? In my mind, I picture a weighted rider on that Specialized frame lowering the BB, slackening both the HA and the STA, and lowering the COM of everything.
I really like this talk, although I don’t understand everything. Can someone please explain to me the part with the stem length and bar rotation? Same bar, same rotation, different stem length = nothing changes. What nothing? It’s obvious, that the bar only moved relatively to the fork shaft, so I would expect any change in relation to the bar. But the distance to the saddle increases/decreases - so there is a relevant change in the overall config. Or do I miss his point here? I swapped several handlebar stems in the past on bikes and could improve the fit/feel significantly. So the length should matter?! Thanks for your help.
Great talk. Wish there was more time at the end to see the rest of the deep dive topics, and some Q and A time would have been nice! Is the remainder of the slide show presentation available online anywhere? Thx
Really interesting material. Rock solid facts that make sense. Mr Verdone shares for free, knowledge acquired through years of hard work.
Many thanks.
Thanks for this great talk. I hope people in the industry really take your thoughts to heart. You're bringing up important points that few people are talking about. Even as a cyclist who started in the last 2 years, it's plainly obvious that most bike "designers" have no idea how bike geometry affects fit and function. Or they know, but they use marketing to cover up their lazy designs so they can maximize profit. Just look at the how the geometry changes across sizing in one model -- what is fixed and what is changing -- and it should be clear to anyone that the bike will not handle the same across the entire size range. If it doesn't handle similarly, is it really designed for the same purpose? Should it be called the same thing? People at the ends of the size spectrum experience this all the time. We get compromised bikes that feel nothing like what has been advertised.
Bike designers need to understand that bikes are an interface between the rider and the terrain. The bike is the link between the rider's contact points (seat, pedals, handles) and the ground contact point (tires). The bike is a tool that enables the rider to travel through the terrain joyfully and safely. It makes the rider feel comfortable and capable. Designers need to stop designing to marketing's specifications, and start thinking about the user and their needs first. It pisses me off enough to consider getting into framebuilding just so I can experiment and discover things that actually work rather than leaving it up to manufacturers and builders who don't seem to care.
I couldn't go to pbe this year. This is what I was disappointed to be missing. Thanks for doing this Peter.
Thanks a lot Peter for putting this out. This is really great!
I'd push back on the idea that forces normal to the ground should be the ones considered when thinking about fork stanchion flex. When you are going downhill, which is when I'd argue fork performance is most important, I think the forces you care about most are opposite to your direction of movement, which is different than normal to the ground. So while you may get binding in a parking lot with a 63 degree head angle, I think performance could be better on the trail in an enduro context.
Thanks for giving this presentation! Overall I agree that geo charts from manufacturers are largely garbage. And I generally agree with a lot of your bike fit ideas. But I do disagree that head angle and stem length don't matter. At least in my experience, there's a very noticeable change from a 40mm to 50mm stem, and I don't think it's all due to body position differences. I just ordered a 45mm stem to try and will see how that goes. With my ~63.5 static head angle that gets slacker at sag, maybe I'm more sensitive to stem length than you are with steeper head angles.
@@alanbonk3542 I don't believe that the takeaway should be that normal forces are the only ones that matter with stantion bind. I went into great detail about optimization targeting. You can optimize for the 0.1% of a ride where optimizing for extreme downhill performance matters or the 99.9% of the rest of the ride. Or somewhere in between. The point is knowing what you are targeting and why and what costs you will pay for that.
There was another hour of lecture that I was forced to cut off where I would have gone into far more detail on this.
Also, you should have taken away that you need to focus on grip and wheel location rather than head angle and stem length. Make a print. You will quickly find that I'm correct. If you are doing anything without a print, you are just tossing darts in the dark.
When looking at the geometry of a full suspension frame, doesn't it all change once you weight it with a rider? Presuming the answer is "yes," are the geometries presented accounting for this (like, they assume the average rider of an S4 frame is 180 lbs)? In my mind, I picture a weighted rider on that Specialized frame lowering the BB, slackening both the HA and the STA, and lowering the COM of everything.
Oops! 39:49 The audience member asks the same question.
I really like this talk, although I don’t understand everything.
Can someone please explain to me the part with the stem length and bar rotation? Same bar, same rotation, different stem length = nothing changes. What nothing? It’s obvious, that the bar only moved relatively to the fork shaft, so I would expect any change in relation to the bar.
But the distance to the saddle increases/decreases - so there is a relevant change in the overall config.
Or do I miss his point here?
I swapped several handlebar stems in the past on bikes and could improve the fit/feel significantly. So the length should matter?!
Thanks for your help.
the speaker is full of shit; he's just using semantics to sound smart.
safer , smoother steering at very high speed
Great talk. Wish there was more time at the end to see the rest of the deep dive topics, and some Q and A time would have been nice! Is the remainder of the slide show presentation available online anywhere? Thx
Hell yeah
I wish all bike manufacturers would get on board with using Lee McCormacks RAD measurement system.
34.9mm dropper
mike burrows died? RIP :(
15th august
lmao why does he talk like tucker carlson
because they are both full of shit?