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E-bikes and relatively low power lightweight electric motorcycles will be the main transportation method for large parts of the world. Imagine replacing every 2 stroke engine in a Vietnamese city with something clean. Once the tech is affordable enough it would mean a massive improvement in air quality and noise. So what’s a niche or recreational market in some places can be the norm in others.

We spent so much time worrying about pedal kickback that we didn't stop to consider pedal kickforward

The modified one is shown in Blue

Seen this at Bikepark Winterberg on a Santa Cruz V10, never seen a V10 with this setup before.

Looks like a lot of chain slippage.

Bumped into someone who works for a major bike brand. He says their XC 32in bikes are already ready for 2026. They are currently test riding them with modified USD forks. They are waiting for FOX and Rockshox to come out with compatible forks. Maxxis is still getting their 32in tyre range done. Apparently, their taller XC racers are already sold on the new bikes. 32in front and back and also 32in and 29in mullet. Though probably no big wheels on sizes S and XS. He says he expects a lot of 32in stuff to show up at Eurobike.

Haven't seen this posted anywhere. From a Japanese site. Hello, this is Kayaba Corporation. Introducing the new suspension we've developed for e-Bikes. Rough roads, wet roots, rock-strewn trails, no matter how harsh the environment, Kayaba's new e-Bike suspension gives the rider peace of mind and enables them to ride as they wish. This product is based on motorcycle suspension technology and has a design optimized for e-Bikes. By precisely controlling friction and damping force, the tires grip the trail firmly and provide high traction performance in all conditions. It uses low-friction oil seals and bushings made in Japan, and the...

Someone, somewhere just thought, "Challenge accepted."

Bad news for Di2 curious 11-speed LinkGlide lovers like you. This is a clarification about 12-speed vs. 11-speed XTR rear derailleurs, added to the XTR article after we published it due to questions from readers about 11-speed Linkglide options and clarification at Big Blue. Basically, no you can't use a normal M9250 battery-operated Di2 derailleur on a LinkGlide setup, only the M9260 derailleur that hardwires into e-bikes: " The M9250 wireless derailleur is available for 12-speed Hyperglide+ drivetrains only, but can be used on normal bikes or e-bikes. However, there are 12 speed Hyperglide+ and Linkglide 11 speed options for...

Yeah and this makes me think about how the upcoming fox podium or other USD forks could easily be shimmed to fit a 32" wheel. The same thing I did to run a 29" wheel on my shiver SC.

32" wheel on a Lefty? https://www.instagram.com/stories/romeandstuff/3659149975738703182/

I figured since I kicked it off I should also move it 😀

Thanks for all the input, fascinating (to me at least) subject and let's move the discussion here: https://www.vitalmtb.com/forums/hub/flex-stay-discussion-thread

As someone who took part in a flexstay design project, I can confirm that: - The spring force of the flex stay is minimal, relative to the spring force of the shock. As in it barely registers in a meaningful way to the ride quality of the bike. This was measured with instrumentation. The shock tune is all that matters here. - We benchmarked the 2021 Epic EVO when we began our 2025 Rocky Mountain Element project, and yes that EVO frame rides stiff. There was a ton of trail feedback, and the anti rise that results from their flexstay...

This is derailing tech rumours a bit but the chattery feeling is almost certainly due to the effects on braking and not from the impact on the spring rate at the shock. Torsional revolute is the correct model but it's a fairly high rate. With a long lever arm (and a very small angular displacement) like a seat stay this results in low forces at the shock but it transfers big portions of the brake torque from the seatstay to the chainstay. Makes the braking much closer to a single pivot in feel. And before someone else says it this...

Nah. The flex stay only moves a meaningful amount when the shock compresses. The flex stay can be modelled as a revolute joint with a torsional spring around it. If there is any angle change at that joint the shock will move. I've not checked out the kinematics but my suspicion is that the flex stays are only bending a couple of degrees so the effects are negligible anyway. The results people are describing could come from general suspension decisions. To achieve what you're describing the shock would have to be very stiff compared to the rest of the frame...

The damping in the shock will still provide the same damping. Rather than looking at individual links and joints, think about what the suspension package is doing - it's providing a spring and damper system between the front triangle and the rear hub. Springs and dampers don't all have to be co-located (I think cannondale did a DH bike with that concept...) You just need to imagine the bike has two springs, one in the shock and a second on elswhere on the frame. You would maybe run a little less air pressure to compensate.

a thin leaf spring is still a leaf spring. Re: stumpy shock – Maybe that was my issue. Couldn’t stand the digressive shock for some applications and swapped to a stock tune when I blew up the RX tuned shock. I never did run them back to back… either way, EE should be flex stay, stumpy should be proper crab.

One of the local XC racers who I worked with races U23 WC went to a training camp last year in europe with a flex stay bike and i started getting messages about how she should set up the suspension as her and her coach couldn't figure it out. She was racing on a medium frame, but she was over all just too light for the way the flex stay was tuned and she just could not get along with the bike. Allegedly, that bikes frame flex was tuned for 140-190ish expected rider weight for best results. So that bike...

It really depends on the flex stay design. Some stays have more rebound than others. You'll notice newer designs from Cannondale and Rocky Mountain with a thinned out portion to minimize this spring effect. These frames don't need special shock tunes AFAIK. I have the flexstay stumpjumper which has a pretty beefy stay so Specialized used a digressive tune on the DPS shock to tame it. I tried a off the shelf Fox Float and the snap back was too much.