The most techncical review on a steel hardtail! This video tickles an exciting intersection between art and engineering. You can do all the experiments you want, but if the bike does not feel good, you won't enjoy the ride. Conversely, you may love how a bike rides, but none of your analysis can tell you why. In this instance, I am glad the subjective feeling, empirical data, and theory align!

My nose bled after all the data, it was fascinating. Better than any GCN tech vids 😎💯👍 AWESOME! 💯

I'm totally here for that type of content ! Working on the Mechanical vibrations and acoustic field, your analysis is top notch and well "vulgarized" for newbies, well done buddy !

So for marketing, a frame is vertically compliant. But it real life it might actually be horizontal compliance at a specific frequency depending on your setup, speed, and terrain. What the data shows vs what we perceive while riding is amazing

I appreciate the scientific approach. It's frustrating to hear people say that one frame/handlebar/wheelset is more compliant, when they have totally different suspensions, tires, etc.

Matlab is where I spend my time at work and this video speaks to me! As more data comes to light, I wonder if the square taper bottom bracket might get renewed attention as a source of riding comfort given it's supposed higher flex. Analog devices makes mems accelerometers with PDM output (for all purposes, analog) that I've used in some past experiments, including as a very crude bandlimited acoustic guitar pickup. They are good to around 6k . I imagine making a test rig using a handful of these with a multi channel audio recorder like those zoom to facilitate gathering raw accel data for multiple locations in the same run. Anyway, know that the science heavy work is most appreciated even if it doesn't have high appeal to a broad audience. Cheers!

This is the kind of video I want to see! This type of data could be used, for example, to test how much more compliant some wheels are versus others by mounting the sensor at the rear dropout like you mentioned. For example, I’d be really interested in testing a bird spoked wheel versus a standard steel spoked one. For the analysis and visualization of the data, it would be really useful to compare one run of each bike against the other run from that same bike. That would give us an analysis of how much standard variation there is in the data or if we’re getting consistent results. If the results are consistent, then for visualization it would be useful to average the two runs together so that we’re only looking at two lines instead of four. Thank you so much for publishing this video and great work! I know how time consuming the testing and component swap is, not even to mention the time of condensing it all into a video and editing it as well as you did.

Huge shout-out for your concise explanation on your method of data analysis. Clearly a complex topic I can barely comprehend, but you did an excellent job of making the topic approachable and digestible. You are providing a style of content that is completely unmatched in the scene of outdoor gear reviews and many science focused channels could stand to catch up to your quality. Chapeau

Such a beautiful video. I didn't understand a word, but enough for me to subscribe to the channel. You'll never know, I might even learn something...You are one of the people, who make the world a better place to live. Thank you!

This video rules. I appreciate the rigor you put this experiment through and the effort made to translate it into layperson's terms. Kudos!

It would be interesting to plot points at the bottom bracket, top of the seat tube, and at the saddle clamp to see if there's a big difference between the 2 frames as well for that. Vertical compliance while seated is more a function of how much your seatpost can bend backwards rather than through the frame, right? Though, since you were on your mtb, I'm guessing you were out of the saddle more, so you would be feeling compliance through the pedals. So the lateral flex might make sense for that since cranks and pedals are more like levers on a frame, right? I'm not an engineer at all, so I'm probably way off base on everything. : )

Your feet being off center from the fore aft axis of the bike, I think the compliance you feel at the pedals might actually be torsional compliance about the bottom bracket. Might want to look at the rotational data about the fore aft axis. OR just measure vertical accel at the end of the pedals. Also, looking into the frequency domain, my feeling is that a "compliant" frame should look more like a low pass filter (more low frequency vibration, and less high frequency).

That makes sense because we don’t often hit bumps and rocks straight on so that lateral compliance is what we feel. Tube shapes and wall thickness is probably more important than material or other geometric aspects. And when seated you get a lot of flex from the seat post and saddle. Plus tire pressures have a huge effect.

Hey Nolan, as a fellow Mech, in the absence of building a test stand to directly + repeatedly measure the actual deflection, I wonder what kind of results you would get by adhering strain gauges to the back and chain stays and rerun the same test. I’ve not had to deal with as noisy a set of data as that would be first hand, but would love to see you try😂. (Maybe some student labor can help figure it out) Anyway, I’m the kind of nerd who would love to see more PSDs in my bike content, so thank you for going all in on the actual engineering experimentation!

This video is awesome, Nolan! So great to see your data and hear you explain it all so well. 👏🏼

I greatly appreciate your work here. It is so important to show what is actually going on. Would be neat if you'd contrast level of variance between frames an 2-5 psi tire pressure difference to show flow important tires are compared to frame choice. Also your results This track with an experiment we did at the university years back but we had to use students in our group and mask the frame to do some level of blinding. We tested road , trekking and MTB frame with same wheels etc and we basically found it was all a wash they were not cyclists but even I failed to identify what was more compliant but it wasn't the ~33% spread as with others... But it was still sobering how much expectations played a role in perception of comfort/ compliance. Runs were on cracked pavement and cobbles in 2000s uni didn't want to give us the expensive accelerometer dataloggers and the were being used in seat dampening tuning for trucks.

It would appear to agree with the experiences of both Jan Heine and Grant Petersen, whose bikes have a fair amount of what I think of as "torsional compliance" around the BB. One can see, e.g. a Rivendell Rambouillet wind up several degrees clockwise then counter-clockwise as viewed from behind, and then spring back to the central position as one pedals hard. The feel is one of getting in sync with the frame, and it is not a slow bike despite having the traits so many people associate with being 'slow'. Also, the give makes it a lot less hard on the knees, and one doesn't feel like a sharp bottoming out of the pedals. It's kind of hard to put into words that people are used to, so it tends to get discounted.

As someone who studied art and cultural history and works with fiction writers for a living, the details were nearly impenetrable to me. As someone with a layman’s interest in science and engineering, the broad stroke observations and conclusions were fascinating. Thanks!

This was a very fun and informative video Im glad to have someone actually take measurements to validate claims of compliance - i have always heard conflicting arguments about stiffness and material choice being essentially nullified by structural design, which had always felt logical. Its great to start taking the data to investigate why we think we feel what we do. Id love to see this data centric mindset grow in the community

Really well done. Your rigorous approach and transparency on the methodology are great!

Very interesting methodology. What I think is missing is the measurement performed at the top end of the seat tube. That's where people try to maximize compliance. The bottom brackets are always designed to have very little vertical compliance so that your power when climbing isn't wasted on the compliant frame. So these results do not surprise me. They even always market themselves as having stiffer bottom brackets.

Great video. Fantastic to see you applying this kind of rigor to bicycles. I first learned of fast fourier transforms 30 years ago, in a signal analysis class at college. The concept blew my mind then, and still does. 'if you make more videos like this, I for one will definitely be watching. Thanks.

As always , another great video. Very interesting results , looking forward to more of these type of videos from you. You are one very intelligent guy!!

Hi Nolan! Im no engineer, but props to dumbing down all the information, and doing all the experiments and lastly moving all the kona parts to the neuhaus!

9:40 wouldn't you expect lower vibration at the bottom bracket simply due to the fact that it's midway between the two wheels? When you hit a bump, the vertical travel measured at the axle of the wheel is going to be about as much as the size of the bump, but midway between the two wheels it's only going to be about half as much.

Wow Nolan, fantastic video! I heard you discuss it with Russ the other day and was hoping it would drop soon. I'm no engineer, but it seems doubtful that there is much vertical compliance (as you found, and for the reasons you already stated). Somewhat similar type of confusion re: what we feel vs the cause w/tires. Generations of riders were certain that skinny tires are faster because they 'feel' faster because people felt the road buzz. But the evidence continues to mount that this feeling is wrong.

Great work! One thing to say about the vertical vibration being lower at the bottom bracket than the rear axle for both bikes is that this doesn't mean both bikes have some measurable vertical compliance. This could be due to the BB accelerometer being closer to the fork and further from the rear axle. The amplitude of vibration will be less for purely geometric reasons (like sitting closer to the middle of a seesaw) even if both frames are effectively rigid in the vertical plane.

Thanks for the effort to share your results. I too am a keen hardtail rider. I recently discovered the torsional stiffness of the crankset had a very noticeable effect on how jarring a small landing was at my ankles. I became so interested in perceived differences that I developed a way to measure twisting give of all my crankset sets. I now use an older deore crank on my Ibis DV9. The turbine cranks with a 30mm spindle were least compliant. I now will check the side to side stiffness at the bb of a carbon DV9 and a heavy steel frame!

Fascinating stuff, really enjoy the science videos. Riding a steel rigid bike with 270 lbs between me and my child on a MacRide I can see their head bobbing up and down and feel the flex standing pedaling up a hill. Not really sure which way the frame is actually flexing, but is is significant.

This is great. I`d love to see more of such rigorous experiments. Subscribed.

Great video thanks for not dialing it back!

Excellent analysis. I’m riding the same bike on technical trails in reunion island. Tested with both 29’’ wheels and 27.5 ‘’ plus wheels, and a long experience in hardtails. With 27.5 plus wheels (3’’ at 0,8 bar in front and 2.8 ‘’ at 1 bar in rear), i can’t return to 29’’ wheels. Only if you’re a chrono hunter, the plus format on hardtails is more fun and definitely more comfy;

Fantastic analysis, nicely done! Fits with some observations published by Alee Denham of Cyclingabout. For further nerdy analyses, seek out "Why It's Impossible For Steel Frames To Be More Comfortable Than Aluminium".

Really cool video! That accelerometer setup is awesome! It would be super interesting if you got a bolt on seat stay brace made up. Then out of curiosity see what the runs on the new house look like. I remember when I made a hard tail back in school the rear end stiffened up a lot after welding the chain stay and seat stay braces in. Ive has allot of questions in this realm recently trying to explain why certain bikes I have ride way better than others. Keep this type of content coming🤘

Nicely done! Going in, I had reservations on the data because you first only show the accelerometer at the axle, and I was like... what??? But you explain this and the outcome of your experiment is very interesting. Thanks for doing this and your well articulated explanation of the data! I have designed a LOT of bikes in my 35+ year career in the bike industry, and we generally quantify vertical compliance at the saddle. Because with road and gravel bikes, this is the place where vertical compliance matters most, this is where it's done. For a lot of obvious reasons, this is not as relevant to a mountain bike, but it's still not wholly irrelevant either. When testing a frame for full ISO testing, there is a vertical fatigue test, but this test can of course be run with a single force load into the 'saddle' with a very measurable amount of deflection. The reason this is still somewhat relevant to a hardtail mountain bike is that the seatpost is typically an 'infinitely stiff' steel bar (nothing is infinitely stiff, of course, but for the purposes of the test, the frame is doing all of the flexing and this tester post is isolating the frame vs. allowing flex in the seatpost as well). This denotes some amount of vertical compliance through the frame, not at the bottom bracket, but rather through the whole frame itself, from axle to axle. I think compliance is more a factor of how the BB hangs between the two axles, like a hammock or skateboard. When you're on a long board, your damping is coming from the flex in the deck, not the wheels or trucks. I wonder about a couple of things: what would the data set look like if you did the same exact test but tried to isolate the frame even more by running 30 psi in the tires instead of 20? I also wonder how some strain gauges running along the top of the chain stays and/or seat stays would look in comparison. Anyway, great stuff!

That was bad ass, Nolan. Super engaging video. Thanks!

Arm chair here: This is great. I'd love to see a bigger replicate set with runs from people who don't have a pre-formed opinion on the bikes. Maybe you could have students do it. And as an engineer, how could you try to find frame properties that correspond to your result? Is it a steel v aluminum question? Or the specific steel and aluminum alloys used? The tube properties? The welds? How would we know. Given that the wisdom on bike tires has gone 180 since I started riding , vertical compliance being a myth would not surprise me. But why would lateral compliance be perceived as more forgiving? Is it that energy is out of the frame before it gets to your hands and rear? I hope this video sparks a good conversation.

🤯 Outstanding! I like the way you explained everything. The science hat was perfect. Thank you. Keep the great content coming. Ride safe and have fun. I think I know how, when & why my last frame cracked.

In an earlier life I worked on defense electronics. We used a pretty burly vibration table as part of the qualification for things like vibration sensitivity of VCO’s, and I have really wished something like it could be used to show the actual frequency response of a bike frame. The drive was a pseudo white noise (calibrated via the on-platten accelerometer), but it could be setup for other stimuli. An accelerometer on the platten surface would provide the denominator, while a frame mounted accelerometer on the three touch points could provide the numerators so that dampening or amplification of vibration vs. frequency could be plotted. It would make very light work of comparing tires, frames, seat posts and handlebars.

Absolutely loved this video, definitely here for more of it. Peak Torque might have some thoughts on this too--he's made some videos in the past outlying the engineering behind "vertical compliance" and why it's fake. Putting the accelerometer around the midpoint of the seat tube and underneath the saddle would be very interesting too--maybe the Neuhaus reduces vibrations even further by those points.

I see some parallels to work done on stiffness of wheels. Guy at northwestern showed that it was rim torsional stiffness that was the main contributor to wheel lateral stiffness. Basically, box section rims deform locally at the contact point because the rims have low torsional stiffness and it has very little to do with rim lateral or radial stiffness. Make the rim a bit deeper and the wheel starts to get rapidly stiffer laterally. ❤I certainly have a set of tubular box section rims that are my first choice for roubaix type races. I find them to be very surefooted and comfortable. They appear to deform to the ruts by deforming laterally and finding grip rather than bouncing off or deforming vertically. I would say that this is the same for frames. They are more compliant because thye deform side to side because of torsional stiffness reasons. You can get too much not his though, I had a cross frame with a lot of rear wheel wag that was an amazing descender on rough surfaces but horrible when sprinting or climbing as it would wag all over the place under power and was very unpredictable when cornering and would lose traction randomly.

Really interesting experiment. Looking forward to what comes next.

Nice experiment. I always wondered about compliance but I never really could tell differences. Thanks for taking the time to help us understand this a bit better.

Good video you deserve more subs, constructively I’d suggest bonding any accelerometer to the surface area of measurement. For example directly to head of the rear axle using an epoxy not so easy to remove post test, but would guarantee you don’t isolate some of the harmonics like the cable tie setup. Oh and give that cap to Dr ‘Ouchy he needs it more than you!

It’s great to see some actual data driven analysis on here! I’m an ee working on different kinds of vibrations, the thing that I would be interested in comparing would be data for a smaller section, ie a step change from one height to another, to see how that was propagated through the frame. Because this data is an accumulation of a longer period, and compliance is something you feel at particular points, ie a stiff frame and a compliant one would feel relatively the same on a smooth section, you’d only feel the compliance at particular instantaneous points. I think this steady state data may be masking more interesting things that occur instantaneously when you hit something.

You sir would be overqualified for the dilettante of the year. Kudos.

Very cool, Thanks, You should share this with Steve from hard tail party 👍

I would think measuring the vibrations at the rear axle and TOP of the seat tube would show more of what you feel (since you were presumably sitting on the seat). I have an old Cervelo RS from 2010 and the seat stays are pencil-thin and not even straight tubes - they are purposely arc-shaped to allow them to flex and minimize the vibration felt in the seat. The chain stays are stiff and straight to maintain their shape when power is applied to the cranks and keep the bike frame from deforming just from pedal forces. Curious if you ran those trails again and took the data from the top of the seat tube what differences you might see. Also, there is likely a lot of variation in each run because your wheel didn’t travel over the exact same path each time. To help better understand the “input” vs “output” vibration, you should consider dividing the data (point by point - easy with Marla) to reveal the transfer function. You may need to offset the data in the time domain a bit to account for propagation delay?

Great work! Impressive how you were able to tease out data to reflect that difference in perceived comfort. I would love to hear a followup on how that feeling of greater BB compliance impacts subjective feeling when pedaling hard like on a climb.

I loved the experiment design, especially adding the control at the rear axel. It made the data so much more definitive.

This was awesome Nolan! It would be interesting to see what differences one might find in material, e.g. steel vs. titanium. Might be able to help with that soon if you're interested. BTW, love the idea of mixing your bicycle engineering program work into the channel.

Great vid!

This might also explain rear chainstay shapes as well. As most of the time they are ovalized vertically. In part for tire and chainring clearance, but this also should help with torsional flex instead instead of horizontal flex.

It would be pretty cool to see all hardtails spec'd out with a "tested" lateral frame compliance number. Though it would be a challenge to standardize the test

Yes yes yes finally a voice of reason!

Others may have asked already, but I would be curious to see data taken from the rear axle and seat collar. While one is generally only occasionally in the saddle on a mtb the data would be of interest for gravel/road frames. Cheers, great video

This is great stuff! It sounds like your observations support the historical description of frames "planing". I would love to see this type of setup measure other things--seatpost flex, handlebar/stem flex etc. Outside of bikes I'd be really interested to see if this type of equipment can answer whether wood or fiberglass tool handles transmit vibration to users differently.

Thanks for doing this, great job on figuring out a way to test. Given the constraints of the rear triangle not offering vertical moment, I kinda assumed when I think I can feel a ride quality difference in a bike there were several possibilities. Once is as you tested, compliance in another direction. I have also though that there might be flex at various major junctures, bb, headtube that would diffuse the trail impacts to feet/hands/ass. I don't know how easy this is the to test. The last thought is that various tubes absorb vibration differently. In this case, you could measure at the drop out, then zip tie 2/3rds the way up the seat stay and see if there was a difference. Anywho, great stuff, thanks for taking the time to run through this widespread concept. I know want to know how the bike industry measures this or if consumers just get the buzz words.

Very interesting look at the “feel” of steel that is thrown around in conversations. With that in mind perhaps the “contact points” are where this feel can be analyzed if possible. The grips,the pedals and the saddle. I agree that lateral movement is probably more significant but I would speculate that thin wall seat stays and chain stays would have some vertical movement. Just a thought

I have so many questions for wheel makers now.

would be cool to record the same data comparing wheels/tires. really cool and informative video, thanks!

Excellent video. Now do a carbon frame vs. aluminum! Just want to see how much they differ.

This makes a lot of sense given the structure of a typical diamond-shaped bicycle frame. I wonder if there'd be any difference for bikes that have the seattube more-or-less decoupled from the toptube/seatstay junction, like the Trek isospeed frames.

Super cool expt. Appreciate the rear axle control. I might have placed the sensors at the contact points (saddle, handlebar/stem, cranks) instead of the BB, but i understand your reasoning. The other thing that comes to mind is you mentioned the test runs taking place on a downhill stretch - I assume you've corrected for that (or that it's insignificant enough to ignore) when looking at the Z axis data.

Would be interesting to see this experiment conducted on a technical, chunky, hard hitting trail to put the rear triangles under much higher stress and force. I will say your explanation of lateral vs. vertical compliance makes a lot of sense given the general construction and layout of tubes on the rear triangle (Also noticed the Neuhaus has no bridges on either stays, which perhaps helps?). I've stretched rear chain stays of older bikes in the past to fit slightly wider hubs in the past so definitely more give on the lateral plane. Very interesting indeed. Nice one.

Wow! That was so interesting! Would be cool to know how much would some of the other parts affect this results to have something to relate.

I’d like to the data when you place the accelerometers closer to the touchpoints of each bike, e.g., at the top of the seat tube and headset (so the flex of the different seatposts and stems/handlebars aren’t captured).

Love the data and analysis!

Wishbone vs regular seat-stays? Longer seat/ chain stays on a laterally rigid frame. Great work, btw👍👍👍

Try it out with the cheapest crankset with the most lateral flex you can find to see how it feels. (or modify/make a pair with a flat flexy section in the middle of the arm)

World be great to see a comparison between steel, carbon and alu sa well!

You’re giving me bad memories of college Fourier analysis…. I survived it…and still don’t fully understand it.

(Richard here0. Absolutely interesting!!!!! I draw no conclusions that will affect my riding but I loved your thoroughness to the subject. (One of the many reasons I watch regularly)

the frame flex in the front has a signifikant impact to the ridefeeling - if you mount a rigid fork and measure the equivalent to the break stiffness - there may be e certain difference between the two

Awesome! That's one of the many reasons i am subbed. Also, as a Chemist, I am a big fan of data in general :) - Very cool!

You’re giving me bad memories of college Fourier analysis…. I survived it…and still don’t fully understand it. I’d be interested to see an analysis of compliance due to a carbon seatpost on an Alu gravel bike .. mine rides a bit harsh.

I ride 2 hardtails, a Ragley Big Al and a steel Esker Japhy and think a lot on this subject. I love both bikes but they are different in how they feel through the pedals…and I ride clipped in candy pedals with stiff xc shoes! If I extend the Japhy chainstay so it is matched, or as close as possible in length to the aluminum Big Al, there is quite a difference in feel on these two bikes. Well, even on the Japhy’s shortest chainstay length there is a difference in feel. I say “different” because the details just remain elusive as what the hell is really going on when each bike is ridden hard. But it is definitely different! Well, I do have a favorite and it is the steel bike. Long rides or really going for it on rough terrain, a good steel frame just has that feel in pedals and also how bike kinda moves with you. I don’t know why but the bumps, the rough, the vibrations…all seem just right on steel.

Great job! With data being quantified this way will defo stir up the bike industry....especially, the believer.

Hey Nolan, great video. As a bike rider myself and a mechanical engineer here goes a question for you. Do you think that the chain stay and seat stay flexing outwards from the frame's vertical plane of symmetry would result in the compliance felt by the riders of a hardtail? Maybe a FEM model of the two frames with their particular geometrical features would give this answer. Thanks a lot and keep posting videos like that!

I love this video! ❤❤❤I wish my teachers would have used examples like this, maybe I would have retained more info from school. Your students are truly lucky. Was there no difference in the fore-aft frequency?

As I see it, frame compliance is far more significant in a road bike than a gravel or mountain bike. If a frame has a few mm of compliance that would be a much bigger proportion of the compliance in a road tyre compared to a mtb tyre. It would be really interesting to see a similar exercise comparing a stiff road frame to a compliant road frame.

Additionally...thanks for pointing out that Yost labs unit! It loks quite useful.

Great video debunking marketing hype, forum ignorance and blind material loyalty.

congrats on a very interesting video, if i may i´d suggest controlling for front fork, as the vibration you picked up at the bb will reflect whats going on at the front axle, especially at the lower frequency ranges, also with some of the more extreme head angle bikes now, mid range forks really struggle with stiction on less than very steep terrain and that might throw the comparison off.

Fantastic vid - keep these deep dive data driven videos coming!

It makes sense to me. Energy needs to be transferred and dampened and dissipated, whether by allowing vertical or lateral frame flexing. It doesn't matter the direction as long as there is a way to transfer and dissipate the energy.

Compliance means bend or flex, right? Do we want to measure flex at the handlebars, pedals or seat? Do the tires provide a lot more flex than a frame?

I would be interested in a comparison with a well designed CFRP frame. It may be that the isotropic nature of alloys is very limiting in the differential stiffness that can be achieved; IE you can't uncouple the vertical and horizontal deflections very much with that material selection. Increased stiffness in one area will likely come with an increase elsewhere, and vice versa.

(before watching) Love you channel. Thx for new interesting and in depth reviews .. keep it up (after watching) wow..went 1 mile over my head but I love science and would love to know if you would run same experiment with Ritchey Ultra frame..(more reasonable priced)

Thanks for the insights. I’d be interested to see data comparing a salsa Fargo to the cutthroat. It would be interesting to see how the marketing of the carbon frame holds up against the data. I’ve owned a fargo and two cutthroats. All have been comfortable bikes the current gen cutthroat does seem to smooth out the bumps the most.

I feel like non-marketing engineers have been saying for years that vertical compliance just isn't a thing. There's certainly a subjective difference between bikes, but I've never seen any evidence of vertical compliance being meaningfully different between unsuspended bike frames. Wheels and tyres, sure. (And even with wheels, there's been talk over the last few years that maybe a laterally stiff wheel isn't the best for control OR comfort, particularly while mountain biking.)

Cool to see the analysis. It would be neat to run the same test on a full sus bike just to really show the difference.

Hi, can the vertical compliance in a frame come from the top tube bending? I have noticed on my slo-motions that my hardtail’s top tube slightly flexes on big impacts (handlebars also flex). Does this explain the ‘vertical flex’ thing or is the rear the only part of the frame that should be flexing. Thank you

Agree on the surprise, could have logged one by the toptube headset and plotted axle-bb-headset A vs B to fully capture frame lateral deflection. Would wonder about rear triangle tubes lenght, if there is any absolute deflection / tube lenght ratios that could tell us anything (more so deflection as a result of lenght vs deflection as a result of material; ultimately not what we're after). Thanks for the share

I'd be really interested in data from the sensor placed at the top of the seat tube.

i loved this! great job!

Fourier Transforms Nolan oh my god. (loved the video)

Interesting experiment, thanks for doing it! I hope you don't mind me asking: what is your day job?

You could actually take this one step further to prove the exact same thing for Steel vs Alloy vs Titanium. You'll likely return with the same exact results as the triangle/truss structure is not designed to flex. This may hurt the egos of all the "Steel is real" or "Titanium is the best" crowd. Anecdotally, I had the Honzo frame for a short time and sold it very shortly after due to the harshness. I replaced it with a Santa Cruz Chameleon in alloy which rode a bit less harsh, and was lighter. CyclingAbout also did a YT video on this content, and included the difference between metals, but his work was based on the research of others.

Data is fun. I wonder if a motioncapture video of your position and movement on the bike would be able to give some insight into your ride feel. I know it is close to impossible, but nevertheless that data would be fun to dive into. Do you have any knowledge of the material/construction differences between the bikes (steel isn't just steel) and tube shapes and welding technics. The rabbithole goes on and on. Well great videos. Love them.