Hello Vital MTB Visitor,
We’re conducting a survey and would appreciate your input. Your answers will help Vital and the MTB industry better understand what riders like you want. Survey results will be used to recognize top brands. Make your voice heard!
Five lucky people will be selected at random to win a Vital MTB t-shirt.
Thanks in advance,
The Vital MTB Crew
It's more like the Wild IMO with the way the frame brace is designed
The rocker pivot says "open" and "close" (i think) it's possible that both sides of the link could be connected then disconnected to tune stiffness. But it's connected to a trunnion shock so that wouldn't do much. Any other guesses for the open and closed markings?
Couldn't that just be indications of tightening direction and torque spec? Fairly common on many linkage bolts across brands.
Amazing investigatory journalism again from our beloved forum nerds. Here's a brief interview with the Fox marketing team to see how they're feeling right now: https://www.youtube.com/watch?v=3CVDFksacsY&t=81s
you're probably right haha
Considering market issues, it's very smart to have one frame serve multiple disciplines...
Lapierre also did that with the Spicy if I remember correctly.
Will Fox stop saying it's just a prototype now? Excellent choice going with a 20mm axle for the single crown version.
Does this mean the inverted 40 will get another shot?
From a buyers perspective, 20mm axle sucks, as DH bikes seem to be fading, and the popularity of DH hubs with it. I’m assuming it has some serious upsides for stiffness etc. But most will need a new hub, which is like $100-200 + spokes and labor. Worse if you have multiple bikes because they may no longer be swap able between bikes.
assuming the RR sticker means that's from richie's bike, that fork probably is a prototype.
Possible that they offer a 15mm conversion kit like the Marzocchi DJ fork? Probably not the best solution, but depending on the dropouts, it could be an option..
That is true, but Fox wouldn't have all build data on the website listed by serial number if it was still just a RAD project. The inverted Fox fork is going to be released.
Aye, it comes with swappable rockers for both pivot configurations, and a yoke to fit a 205x65 shock, without the yoke and with a 225x75 shock it has it's full DH travel.
Gotta agree... It's got a serial number and it's in the system.. Seems likely that production is underway and will be released sooner than later..
Probably my favorite part about hope hubs, and one of the reason I built wheels with them for my Madonna, being you can swap the link and get 175mm of travel I was planning on getting a dh38 and dropping the travel to 190 for racing dh this year.
Hope front hubs for life and luckily the list of 148 DH bikes is growing day by day. (Canyon, YT, Transition, GT, Forbidden, Spesh, Frameworks) Glad the industry is having to cave a little on these incremental improvements that could end up robbing you of a day of riding if you don’t have backup parts. Very interested to see if the new Demo is still 148.
From a stiffness standpoint 20mm is the way to go. I tested a 2024(38mm) Boxxer that was converted to 15mm axle and it was a major difference in twisting feel when the weight was loaded. Upside down fork the 20mm will prob be a big jump in the right direction.
I don't know.. Many previous USD forks were 20mm axles.. I'm curious if the potentially bigger chassis has more of effect on things than the axle.. As I understand it, most of the flex people feel when they put the front wheel between their legs and twist is happening where the stanchions enter the uppers and not so much at the axle..
not according to intend, they had it first and found no difference, getting the upper chassis right is more important
The shiver SC that I had on my Giant AC1 back in the day was a noodle. This was back when I probably weighed 135lbs, no axle was going to fix that wobbly fork. I loved it, but it didn’t change the fact that that it was flexy AF. I agree that to make a solid USD fork it’s a package deal. Putting a 20mm axle is just another bandaid. My 2 cents…
How was the conversion handled? Could the adapters have some slack in how they interfaced with the lowers and the axle thus severely lowering the apparent stiffness?
It's not just the diameter of the axle that is at play here. It's the thickness of it and how you anchor it in the lowers that also plays a big role.
And yet at the rear where most of the rider weight is and where most of the heavy hits are taken we comfortably run 12mm hollow axles at lengths that are 30% higher. Weird.
But you also have a triangle connecting the rear wheel to the front or at least a single piece box section, not a bushinged tube in tube arrangement where the two tubes can rotate one relative to the other. These details do wonders for stiffness. QED, 20 years ago it was completely normal to run a 20 mm axle in the front and a QR in the back.
It still says prototype on the Fox page. I imagine everything gets a serial and data page whether it gets to production or not.
I have to say I find it an odd choice from Fox to go the usd route. I feel this will most likely be a limited qty thing rather than full blown offering to replace the 38.
I reckon the new demo is gonna solve the 148 issue by using a 148 super-wide hub like the session is doing. In my eyes this is exactly what specialized is up to rn. Only applies to the r2r builds they are going to release obviously.
i‘m 99,9% confident that the podium USD fork won‘t replace the 38 and will just run besides it, probably even limited.
Awesome you brought the qr in to equation, old qts had a higher clamping force than thru axles we run these days, essentially making dropouts and steel axle one piece even though they were much smaller diameter (9mm at 100mm width vs 15mm at 110mm) I would guess they weren't much less stiff. One popular bike channel compared the two few years ago, don't remember his name but he was engineer and I think he worked with hambini on some videos.
Peak torque tested the clamping force of QR skewers and compared that to the current crop of bolt-on axles.
A few problems.
One, a QR has an open dropout which means the axle is not fully enclosed plus it barely even fits into the frame length wise. A through axle these days has 10+ mm of axle interfacing the frame (even more for a fork) length wise, which means the axle can't rotate around the dropout (like the QR essentially could), it has to be bent if the dropout sides go out of alignment. This gives a lot more stiffness connecting the two sides.
Two, peak torque did not test QR through axles (Maxle) and their axial clamping forces (even though I asked him to do it...). Might be that it's higher in that case. The QR skewer is only 5 mm thick which makes it somewhat elastic, even if it's aluminium the cross section of the average 12 or 15 mm through axle is quite possibly bigger enough to offset lower stiffness of aluminium in general to make the axle, essentially, a stiffer spring. If you preload it by the same amount with the came (give it the same stretch), the clamping force will be the same. And I would not be surprised if the clamping force of a QR Maxle is higher than a bolt on Maxle (even more so when you bolt the axle with a multitool because that's what you have at the side of the trail).
FWIW, I think it's advised not to use QR axles in UDH hangers/Transmission derailleurs. A higher clamping force causing issues with the nut thread (either hanger or derailleur) is the first thing that comes to mind (though the fine thread pitch used with UDH is stronger than a coarser thread and it's usually the bolt that's stripped before the nut is). I run Maxle QRs front and back regardless.
Yes many factors with axle thickness can play a roll. The clamps make a giant change as well. The dorado going from 1 bolt upper to 2 bolt upper added a lot of torsional rigidity.
Quoting Roost here to keep it in line, but not calling you out specifically because so much talk on DH hubs.
Here is the thing... any rider purchasing this fork (by itself or on a bike) will be running hubs that can do both 15 and 20mm boost spacing. This isnt a new thing to have a convertibale hoba and most (couple small outliers) 15mm x110 boost hubs can convert to 20 mm with an endcap swap. This isn't a major chang in anyones hub and usually shouldnt require a relace or anything like that.
Fox didnt go with some proprietary unknown standard. They took on eof the most common standards in the industry for this... suprised that this is such an "issue" for so many. This is a completely normal hub that most of us tech nerds in here have a compatible hub for.
yes if you go from a 20mm hubs all of them can go down to 15mm with different end cap. But quite a few native 15mm front hub are not able to to go up to 20mm because they use smaller bearing either 17 or 18mm ID bearing like the recent One Up hubset.