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it just needs to be pending, not a patent granted, which would allow for years of development progress ahead of others. By the time others were able capitalize, we would be on the 7 bar linkages, with low pivots....
yup, and ever since everyone settled on the post mount standard, brakes almost always use an adaptor anyway........so it wouldn't really be that big of a deal to make callipers with different bolt spacing.
As for bottom loading pads - I take the wheel out to clean the calliper and reset the pistons anyway, so it makes literally no difference. Even with top loading pads, if the old pads were slightly worn getting the new pads in was still a pain if you left the wheel in
weight,
I think the rollout on long travel bikes made a tonne of sense, and likely the largest segment of new, premium bikes being sold
I take the wheel out, but I still watch the work from the hole on the top, while mounted to the bike/fork, are you flipping the bike over? removing the caliper?
Also makes micro setting adjustments easy to be able to see where things are centered
From the other site, interviewing the Norco design team on the new proto downhill bike. Thought I'd share this bit about a patent for a link that adjusts progression without affecting anything else? Don't get how this is possible, but they're smarter than me so who knows?
"We’ve filed two patents based on the suspension layout and kinematic adjustment designed into the new DH race bike... The second patent applies to the method of leverage curve progression adjustment we’ve designed into the bike which allows us to alter the level of support from the rear suspension in isolation without needing to alter shock tune, damper settings, spring rate or shock pressure."
I was scratching my head because I would assume a different leverage profile always necessitates a different shock tune, damper settings, spring rate, etc. Curious on your thoughts.
Shocks are often tuned off of average leverage ratio so as long as travel remains the same then general tuning would still be accurate. If tune is done for a specific spot in travel then that's out the window as soon as leverage curve changes. Damping force as felt at the wheel is inversely proportional to leverage ratio squared for anyone who's curious.
As for spring rate or shock pressure, increasing progression while travel remains fixed generally results in a higher leverage ratio at the sag point. So to keep the same sag point you'd need to increase spring rate/pressure or you'd be sitting lower. If you say that leverage ratio at sag point remains the same, then increasing progression will decrease travel and then you'd be changing the average leverage ratio around which the shock is tuned. The one way around this would be set it up so that leverage ratio at the sag point is fixed and most the progression change comes from increasing the leverage ratio between sag and top of travel, but that would be a huge limitation in tunability. Also wouldn't be a limitation I would understand. Bottom out resistance is the sum of energy that goes into the spring and energy that is dissipated by the damper so increasing spring rate or damping is the only way to increase bottom out resistance.
I dont really get what they are trying to say though?
You can increase support without change spring or damping settings? Yeah every frame you make more progressive via flip chip will do that.
Nope, if youre changing the progression, be ready to adjust settings for it....
So the fuel EX gen6 with adjustable progression, If you go from linear to progressive, youd have to increase pressure?
Generally more progressive for a given travel amount results in higher leverage ratio at the sag point so higher spring rate or pressure to be at that sag point. This is because wheel travel is the integral of leverage ratio. If you decrease it in one spot you have to increase it in another otherwise there is a travel reduction.
Likely end of the year or early next year. That's the info I was given.
The marketing argument with top loaded pads was also that everything was cooled better as the air could blow through the caliper.
Anywho, most brakes do indeed use adaptors, except for stuff like Zebs where 200 mm rotors are direct mount. That does complicate things a bit. With forks having wider spacing shouldn't be an issue, but with rear brakes there might be some pushback considering there are flat mount MTB frames out there. And given all the marketing messaging how protected the caliper is inside the frame (mounted between the chain and seatstay, making adjustments a huge PITA), I could imagine some pushback on that idea to be honest.
It might be possible to make a wider post mount standard where an adaptor could be used to go to the old caliper? That would shaft people on old bikes that would want to run new brakes, but it's exactly the same situation Transmission has put the same people - you can either run the old stuff on your old bike or the old stuff or Transmission on your new, UDH bike.
Regarding the Norco tidbit, my first reaction (after looking at the Pit Bits 2 days ago) is that they have multiple dogbone and swing links to drive the shock and can play around with that to alter the shape of the leverage ratio. The reaction came as I was looking at it the other day and wondering how high the forces in those small links must be and then instantly thinking this must be it for the patent. There could be something else, but as far as I saw, they are running an inverted horst link with an additional linkage to drive the shock. So kiiiiiinda what Specialized are doing with the Demo conceptually-wise.
Forgive my terrible illustration, but more or less this. I’m guessing in making that lower link much smaller than on the Range they had to get creative to make leverage curve work out and ended up with the linkage driven solution that then had the benefit of more miscellaneous adjustments to play with.
Sounds like a move to a radial mount (ala Hope's 2016 proto bike) would help get around/improve that issue? And make rotor size changes easier too.
No. This has been discussed in the past (not sure if here or not), but bike brakes are mounted with a lot more support than radial mount brakes on motorbikes. The caliper being offset means the caliper isn't only pulled perpendicularly to the bolts, but is actually pushed onto the fork/frame/adapter axially as well. This takes a lot of the load off the bolts and the mounting interface and we can thus run smaller bolts than what would be needed with radial mounting. Plus changing rotor sizes might become a lot more limited (running a 200 or a 220 mm rotor on a 160 mm radial mount would make for some LOOOOOOOOOONG bolts) as you don't want the bolts to be too long.
There is some logic to the madness that is the current post mount standard. What does need to die a painful, but quick death is the 203 mm rotor standard. In a world of 200 mm direct mount interfaces, standardised 20 mm jumps between rotor sizes, 220 mm rotors becoming the norm, etc. how in the hell can we still have 203 mm rotors that are so widespread (is there anyone else besides Sram making 200 mm rotors at all?)?? And then you have 220 and 223 mm rotors, there are some proto 246 mm rotors out there (Neko), etc. It's a clear 'fuck logic, that's why' situation. If 185 mm rotors were able to be done away with, why is the 203 option so persistent?
I would also guess the lack of a need for a dropper post on a dedicated DH frame allowed them to use more of the seat tube for the additional linkage. I'm seconding @Primoz's concern about the high forces going into those dogbone pivots - the upper one in particular has a lot of leverage over the shock link, and I hope they have any potential durability problems sorted if it ever carries over to a production model.
Also, I can't say how accurate this is (to my eyes it seems close, even using a photo for reference, but it's hard to tell), but the linkage could theoretically result in some pretty interesting leverage curves with two inflection points (the only thing similar is the newer Focus JAM/Thron). I highlighted the different 'phases' you could distinguish in the wheel force gradient:
Yellow = soft small-bump, Green = consistent mid-stroke support at/after sag point, Blue = slight reduction for medium/large hit absorption, Magenta = end-stroke/bottom-out support. Overall they might be too subtle to really notice in this implementation (it could just feel pretty linear until the end), but this sort of 'quad-phase' design accounting for medium/large compressions could be pretty interesting compared to the usual 'triple-phase' stuff you hear all the time (small-bump compliance/mid-stroke support/bottom-out prevention) from Canyon, Marin and others.
Sorry but that is not right, if you make leverage curve more progressive with the same starting point and lower end of travel rate,it effectively increases both spring rate and damping (because rear triangle has less leverage over the spring and at the same time it compresses the shock faster which means it will produce more damping force with the same settings).
Damn you with the long post where I want to reply to the last paragraph but have to quote the whole thing lol. You know who came up with the 200mm rotor size right? The same brand that now sells forks with 200mm PM mounts on boxxer and zeb. Guess who is using 203mm direct mount on their forks for a longer? Yep that's right, the other biggest player fox. If you expect those two to deal with that in a manner normal adult would, you are delusional 🙂 203 was and still is legacy standard for dh bikes and even though I'm all for metric system, I never saw any problem with classic 160-180-203. Now add 223mm for wagon wheels and call it a day , because you can run that with standard M6 washers under caliper no problem on RS forks, putting 220mm on fox 40 not so much. On frames it's a moot point since most enduro/dh frames still come with 180mm PM mounts and we have the right adapters for all those sizes already.
I could be misunderstanding, you're an expert, I'm not. But from the article showing a flip chip at the fwd shock mount: "This adjustment at the forward shock mount is not a geometry adjustment but a kinematic position that goes hand in hand with an secondary dog bone link that is specific to the type of shock - air or coil."
I know they say it's for air or coil, but maybe it's more? By altering dogbone and fwd shock mount position they could make a more progressive curve and thus have more sag (with same pressure/spring rate), but by altering the starting point of travel (i.e. raising the unsagged bb height) the geo at sag would be the same. In the quote robot started this with, "method of leverage curve progression adjustment... without needing to alter shock tune, damper settings, spring rate or shock pressure." They don't say that overall travel is kept the same Nor recommended sag. I've no idea if damper settings should stay the same in that situation though. Just a thought.
Or it's just marketing. It does have a slight whiff of "zero compromises" type of marketing speak.
I mean yeah as soon as you get into changing other variables like travel or geo then it’s possible, but those are some very significant variables when it comes to how a bike handles and I’m not sure it would be wise to do that. The other possibility is they are tweaking the leverage curve in. Way where the middle stays the same and only the beginning and end change. This would get you start of stroke sensitivity and end of stroke support while mid-travel stays identical.
Yes,
more than likely youll need to adjust spring rate, which will then in turn affect both rebound, and compression
One thing I’d like to point out is that there isn’t a single region of travel that controls bottom out resistance. Bottom out resistance includes all the work your shock does to slow you down between its initial starting point when you impact and bottom of travel. In the case of a drop to flat it’s the area under that force curve plus whatever amount of damping you’ve chosen to add. So the blue curve has significantly more bottom out resistance than the one that sits below it. I feel like the bike industry perpetuates the idea that just the end of travel region controls bottom out in isolation and it just doesn’t work that way. The best extreme example of the why this is is if you were to make force near zero for all of travel and then spike up to max force at the very end. Mean force an adult male can apply when jumping and stomping with both feet is between 17000 N and 18000 N so easily enough to overwhelm 2300 N at end of travel if early travel provides no resistance. At the end of the day an impact really should be quantified as an energy input though.
*I understand one curve is for wheel force and one is for wheel rate. Just figured I'd use the more linear curve as a comparison since they both end in the same spot.
But then youre just making adjustments at the other end, or bottom out.
Obviously its a "window" that all settings work in, if the progression is a bump of 3%, you might not be changing anything, but is anyone noticing a progression change of 3%?
something like 10% is going to require some changes to your shock settings. You can choose not to touch anything, but youre likely leaving some performance on the table.
Leverage curve for Dissent, to get the three different progressions, youre increasing both the top, and bottom end of the curve, its going to require a different shock setup to get the most out of whats available.
Hum. Possible, but probably less than ideal. And what's the point? Wanting to keep the same base tune is advantageous for spares reduction for pro teams and way simpler if it goes to market. But keeping the same clicks and pressure seems like it'd force changes and overall have more cons than pros. Doesn't make sense. Norco might just be playing mind games?
Newly-posted pic of the Push fork, are those bleed ports?
https://www.instagram.com/p/CvtQCfjuMkI/
Considering that Darrell seems to be all in on coils, I would imagine they're bleed ports and/or oil fittings. *shrug*
Push has used a pneumatic bump stop in their coil fork conversion kit for while, so I wouldn't be at all surprised it this fork used that same tech. That said, I'd agree those look like bleed ports.
Good point about the pneumatic bottom out, but wouldn't that be a spring-side only thing? I've honestly only worked with rear shock stuff from them.
I would hope the fork is more advanced than their acs3, something like the Smashpot with a tunable hydraulic bottom out ( or like the 11.6 if you will )