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WhatsUpCountry Liked a reply to forum topic 2026 MTB Tech Rumors and Innovation - Longer and Slacker

5/19/2026 5:36am
Big if true
This forum topic has 6063 replies.

TEAMROBOT Liked a reply to forum topic 2026 MTB Tech Rumors and Innovation - Longer and Slacker

4/28/2026 2:24am
If you're not from the US and you haven't seen this yet, I can't recommend it enough. It explains a lot:
This forum topic has 6063 replies.
Thanks a lot! I'm working on something like that myself. " Must be used with a fixed rear hub. Any rear hub on the market can be “locked-out” by the way of zip ties." <- This is a bit weird though because the chain moves with the rear wheel all the time. My plan is more about chain retention and...

TheSuspensionLabNZ Liked a reply to forum topic Tuned Mass Dampers and Mountain Bikes

9/6/2024 2:00am
So it took me way to long to stitch these together and export it properly, but I did this test with the tyre at 18psi and 26psi, the 18psi gave the best result. Using parts on hand like some springs around 11.8 N/mm, a 250g mass and a 600g(250+350) mass. (*edit using the 2 opposing springs halves the rate so more like 6 N/mm) The wheel alone is about 1800g so total system about 2.4kg Tyre rates are roughly 35N/mm @ 18psi and 44N/mm at 26psi BUT they are slightly progressive in the first few mm plus I trimmed the...
This forum topic has 184 replies.

sspomer Liked a reply to forum topic Tuned Mass Dampers and Mountain Bikes

9/6/2024 1:42am
seems applicable (sort of). why not just put ebike batteries in one to isolate the weight : )
This forum topic has 184 replies.

pathfindr Added a reply to Tuned Mass Dampers and Mountain Bikes

9/1/2024 3:48pm
I've found the exact springs that the rimpact one uses in my local hardware store, so that alone is making me think that rimpact is only in the early stages of their R&D. Or maybe it just happens to be the right spring rate, I dunno. You could probably calculate the spring stiffness with the damped oscillator model pretty easily...

TheSuspensionLabNZ Liked a reply to forum topic Tuned Mass Dampers and Mountain Bikes

8/31/2024 11:11am
This diagram (taken from Analysis techniques for racecar data acquisition by Jorge Segers) shows the level of vibration passed through when comparing 2 parts of the system (it is simplified for theoretical purposes). 1 on the y-axis means the size/displacement of the vibration output is equal to the input (ie rolling slowly over a large bump, the vehicle rises the same amount as the wheel). A value greater than one happens around the natural frequency where the input gets amplified (movement at the chassis is larger than the bump). Red line = body of the vehicle bouncing on the suspension...
This forum topic has 184 replies.

TheSuspensionLabNZ Liked a reply to forum topic Tuned Mass Dampers and Mountain Bikes

8/31/2024 11:11am
Yeah thats a long term project I am slowly collecting data on....there is a huge difference between casing and compounds. Measuring the force vs displacement curves tells you the change in spring rate and damping from different rubber, and changing spring rate will have a proportional change to frequency Blue line is a Conti Kryptotal DH tyre (note:29") at 23 and 25psi Red line Maxxis DH maxx grip 2.4 x 27.5"@ 23psi Yellow line Maxxis EXO Maxx Terra 2.4x27.5" @ 26psi The gap between the lines is an indication of damping, the EXO has a softer rate and less damping...
This forum topic has 184 replies.

CascadeComponents Liked a reply to forum topic Tuned Mass Dampers and Mountain Bikes

8/31/2024 10:57am
This is one thing I’ve been wondering about. To get say 1lb to have a natural frequency in the realm of braking bumps you need stupidly stiff springs. So stiff they are a little hard to find with meaningful amounts of deflection.
This forum topic has 184 replies.

StudBeefpile Liked a reply to forum topic Tuned Mass Dampers and Mountain Bikes

8/31/2024 10:56am
So, just looking at the rear, this would be more used for counteracting large movements, right? Like when your rear hits a large square edge rock and it gets kicked up? Or do you think its more for small stuff like braking bump chatter? I couldn't imagine it working for small stuff? IDK. Also do you think the one on the fox 40 has its own hsc and lsc clickers ;p
This forum topic has 184 replies.

TimBud Liked a reply to forum topic MTB Tech Rumors and Innovation

8/31/2024 1:38am
No, your comment has been said a million times before and you were clearly just trying to stir.
This forum topic has 30430 replies.

tarekfahmy Liked a reply to forum topic MTB Tech Rumors and Innovation

8/31/2024 12:46am
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This forum topic has 30430 replies.

Primoz Liked a forum topic Are Upside-Down forks really flexy?

8/9/2024 1:36pm
It was last spring, in the beginning of this pandemic that has turned our lives upside down, when we were having heated debates in the Technical Rumours topic regarding suspension, forks, dual crowns, right-side-ups, upside-downs, axle diameters, etc., when I mentioned much of it could be checked using finite element simulation. It was a great project to get into FEA and to have a cool result, but, as is usual for a master procrastinator without a deadline, it took a while to get it done. But get it done I did! So, in this post I will present the results...
This forum topic has 82 replies.