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Did RockShox say why they got rid of the 'touchdown' bypass valve on the new Vivid? Looking at the shim stack documents the old (C1) has the bypass and the new (D1) Vivid does not Any mention of this change is conspicuously absent from any review which is strange considering how much of a selling point that feature was for the last launch

My understanding is that a lot of the magic of the gen 2 Optic was the shock tune of the RS Super Deluxe that came with it, so I would either try to track one of those shocks down or find a smart suspension tuner and see how close you can to that RS tune with a Fox shock. But I think if you just slap a random shock off the shelf you're only going to be experiencing some of the magic of the bike.

Last year, for one of my engineering classes I did a simulation in Ansys titled “The influence of the axle diameter on the torsional stiffness in an USD bicycle fork”. It was an exercise more focused on Ansys, not on being scientific, but still the results were interesting. Here’s a link to the presentation . TLDR: 20mm was only 4% stiffer

In regard to front axles and stiffness of inverted forks, the angular deflection of a shaft is defined as θ=(T*L)/(J*G). The key variables for axles are J (polar moment of inertia since we're talking about circles) and G (shear modulus of the material). J for a circular cross section is J(r1,r2)=(π*((r1^4)-(r2^4)))/2 where r1 is the OD and r2 is the ID (zero if solid). As for G, the shear modulus of steel is approximately 3x that of aluminum. Now for a comparison between 15 and 20 mm axles... Lets say we have a solid 15 mm axle and want to...

7Mesh "leaking" the new Lyrik / Zeb in their 2026 clothing line promo shots. Noticed the air release buttons in crown. https://7mesh.com/en-US/products/mens-glidepath-short-14-in / https://7mesh.com/en-US/products/mens-glidepath-pant

Not only the effect as a lever, also the effect of localized stress through the mounting point instead of through a wider area through the helmet shell plays a big role here. Eg Schumacher's brain damage was caused partly by a camera that split the helmet iirc

Honestly the stock tune is fairly firm as-is.

Excellent thread. Looking at exactly this question the last few months. Ironically, as an upgrade from a Gen 2 Optic. To the Optic owners: do you have another longer travel bike to complement it? It's such a fun bike 90% of the time but in a few situations it would be nice to have an extra 20mm front and rear. And there's not really a weight penalty when the Optic is already built with a Float X, 36, enduro wheels and tires...

Thumbs up for the magazine. I miss print.