I want to know peoples reaction to this video about frame flex. Is it something worth considering or not matter as much as we think? should we emphasize an ultra stiff frame to optimized power transfer
while pedaling and try and gain compliance in other areas such as tire, seat posts, saddles, bar wrap, handlebars, etc?
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[https://www.youtube.com/watch?v=BH\_AL4rxrp8&pp=ygUPYmlrZSBmcmFtZSBmbGV4](https://www.youtube.com/watch?v=BH_AL4rxrp8&pp=ygUPYmlrZSBmcmFtZSBmbGV4)
by Latter-Camera-9972
5 Comments
The spring of a resilient system is extremely important in feel, response, control. See, e.g., fishing rods, violin bows. I find very stiff frames tiring, and more prone to chatter. For example, strong track frames on the road.
My personal taste prefers some amount of resilience that I used to get in steel bikes.
I’m wondering about the character/rate of the return energy. My carbon bike feels a good deal more chunky as compared to the smoothness of my steel bikes, but so many other factors are at play! Regardless, my carbon bike is more resistant to flex, at least on my turbo trainer! It’s also not as comfortable, and was initially sufficiently stiff that I changed from the original modern few-spokes, few-crosses wheels to traditional 32H LF 3x, which balanced it out very much more nicely.
So I see flex well worth considering, but not for efficiency. Feel and comfort.
It might be. This is the concept of planing: [https://www.renehersecycles.com/what-is-planing/](https://www.renehersecycles.com/what-is-planing/)
As far as ride enjoyment goes, I just like the ride quality of an intentionally flexy frame.
The fit is more important. Good carbon bikes are noticeably better as they have a better lay up of fibre. Gives flex where it’s needed like in the stays and not where it’s not like the bottom bracket. Can also be formed into better shapes for areas like bottom bracket and seat stays for virtually no weight. Makes it a superior material IMHO for bikes.
I’ve never seen frame size taken into account in this discussion. I ride most companies’ largest
off-the-shelf frame offering, usually a 61cm/XXL. The largest frame size will flex significantly more than the smallest size because of the difference in the ratio of tube length to diameter/thickness. Also, a taller rider will be, on average, heavier and put out more power, causing the frame to flex even more. For these reasons I much prefer to ride stiffer frames.
A wet noodle of a frame is a problem. If the frame is stiff enough and responsive enough to handle well that’s fine I’ve ridden super rigid inflexible frames and they suck as well. (It’s one of the reasons why everybody hated aluminum bikes when they first hit the market, they were too stiff)
The reason that a lot of people love to ride, titanium and steel is because the frames are just the right amount of flex. An old article in cycling magazine in the 80s referred to it as planing if the frame is just the right amount of flexible for you and your power output it feels better than anything else