On Sunday, September 13, 2020 at 5:09:03 PM UTC-7, William Crowell wrote:
"Then be certain not to watch the video on Canyon by Hambini."
Hope I'm not hijacking the thread, but I would like to ask you guys what you think of Hambini. He does seem to have a rather unusual personality, but I'm not really well-informed enough to judge or criticize him.

He is mostly engaged in aerodynamic engineering since he works designing jet engines for aircraft engine manufacturers. He is extremely good at aerodynamics but he tends to be rather too focused on that sort of crap. For instance, he will say that the fastest tires are a 23 mm tire on the front. Well, from direct experience that IS the fastest tire on perfectly smooth roads in calm conditions. That is not the way the world works though and most of us have discovered that much fatter tires are faster. The tires that the Pro teams are using are 26 mm tubulars and 27 mm tubeless. Someone said that FDJ were using CLINCHERS. Most of the pro's are little guys and so that is wide enough for them. The increase in speed I discovered when I went to 28's were rather shocking. First I installed them on my Time because I simply could NOT ride that Time with high pressure tires on it. It was just too stiff and a 20 mile ride would have saddle sores everywhere. Changing to the 28's was an entirely new world. I could sit on the bike and ride it like a human and do centuries etc. with no problems. Then I started using them on other bikes and again there was a world of difference - the bike spend a lot more time going forward instead of up and down from the road bumps. So while a 23 mm tire may be more aero, fatter tires are still faster because there is more to riding a bike than being aero. And with my big gangly body sticking up in the air, the aerodynamics of the bike is the least drag being presented to the wind. What's more, I am normally the fastest of the groups downhills.

Hambini tends to take one example as indicative of an entire product. In some cases that is proper. He showed cut-a-ways of those Chinese frames constructed with bladders to push the layup out into the mold. This is not good for a couple of reasons - they do not have sufficient pressure to deliver enough power to fit the layers into the mold and this causes wrinkles and voids. And you have to use disposable and therefore really cheap bladders because parts of them will often be left inside of the frame. ANYTHING that causes a difference in rigidity inside of a carbon fiber layup can cause a fracture point. So wrinkles and voids are huge no-nos.

But the alignment of the two halves of the bottom brackets do not necessarily reflect on the product. More on the quality control. You can proclaim the quality control of a frame maker is ****, but not that the frame itself is. Hambini tends to rate things from a one-off perspective. Not that quality control isn't important, especially these days when frames are breaking so seldom that it is giving manufacturers the courage to reduce the lay-ups to save weight and to be able to say "I've got the lightest product". If you have crappy quality control, the best design in the world will not save you from a law suit that can put you out of business. Hambini noticed this in the last analysis of a Look that he made. His older 695 seemed to be better made than the 795 despite the lighter weight of the 795 which should have necessitated far more care on the quality control. I was an engineer but I would design products that made for accurate and easy manufacturing. Hambini seems to be totally disconnected from manufacturing which is a bit odd since accurate manufacturing is what holds jet engines together. They have to have PERFECT balance on the rotating parts because of the speeds of rotation. I suppose large companies like that are so compartmentalized that he leaves things like that up to production engineers.

In any case I like Hambini and watch his postings religiously, but I also recognize his small failings.