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Yes. We had a standard that did not require threads to be cut into either frames *or* the calipers themselves. Roach a thread and you don't need to repair a frame, replace a caliper, or bleed your brake line -- just replace a cheap aluminum adapter.
And don't get me started on how many slightly different lengths of flat-mount brake bolts are out there because every different chainstay depth requires a different bolt.
Flat-mount brakes: brought to you by the same minds that think thru-headset cable/hose routing is a perfectly fine idea.
We are free to disagree on this matter. I think post mount with its manufacturing dimensional requirements makes for a more robust mount. I ain't judging your opinion, just disagreeing.
Hear you on the flat mount dimensional front. The variability there is rather nuts, but by the same token so is the number of adapters necessary for PM or IS mounts. I like the idea of what flat mount can bring to the table for the reasons I listed prev, however the variability between manufacturers and where they chose to set their origins for the design center is much to be desired.
Is anybody on a steel frame really concerned IS isn't sufficiently robust?
also,
"please don't even respond at all" is an excellent, if somewhat abridged, quote.
This is cool, and something I’d like to see with it is what the “median” bike is though the years. What’s that crabbiest crab bike geometry, and how far off that median geo is a selected bike?
Counterpoint: flat mount brakes also require adapters for different rotor sizes, except for the default 140 or 160 mm (depending on frame manufacturer).
For the record, I do not know enough about engineering & frame design to question any of what you said about more efficient loading of the frame/tubing. I assume you're correct in that regard. It's plausible that there are engineering gains achieved by relocating the caliper. But from an end user or mechanic perspective, it's a pain in the ass.
I do wonder if the bolt spacing pattern limits the achievable size/power of calipers. AFAIK only Hope has made a 4-piston flat-mount caliper so far.
You were probably eagerly waiting for another company to step up and enter the pedal/stem/bar market, here you go (some sarcasm detected): https://www.vitalmtb.com/news/press-release/leatt-enters-components-category-pedals-stems-grips-and-handlebars.
Not sure what's meant by that last bit, but no matter.
When I say robust mount, I mean in light of taking cross sectional load off the mount screws as well as creating a stiffer interface between the caliper and the frame, which post mount does. Brake force is applied directly to the mount, not through the screws. Some IS mounts are flexy buggers, which results in noise and worse case, vibration. Post Mount pretty much does away with that. Like all things, end game is about tradeoffs. IS is easier to manufacture, PM creates a better interface.
I hope they're not quoting me and that I'm not in trouble 😅 I sincerely apologise for my part in starting that discussion.
I said it before, I'll say it again. That new UNNO is head and shoulders above any other ebike option right now. Long travel, burly build, still light weight, incredible aesthetics, next gen motor. Price isn't insane either, at least compared to the competition.
How how unfair is it, Cesar is not only a fast rider, hes better looking than all of us and living the dream of being a bike and moto engineer.
https://www.youtube.com/watch?v=DAd4hRvaLrc
bernard walks through his pivot phoenix (raw and 17 q's to follow this week too)
on how many frames is he by now? i have seen so many snapped rear ends before on such a new model on social media
As someone with a front seat on brake mount designs/development for a number of years, there are pros and cons to each mounting method depending on the material and frame design, and the intended customer. Often the intended customer preference outweighs the best possible engineered solution. Shear force loading the caliper bolts is a non-issue in most cycling applications. For a steel frame, the complexity and cost of using either a post mount or direct mount design might go against the simplicity and cost reduction goals of that project. Those customers might prefer something simple, inexpensive, and easy to use. Post or direct mount forgings are also subject to failure at the weld from design or fabrication errors. TLDR; you can't apply a blanket solution for all applications.
Back to rumours; I look forward to evolving brake designs that Sram's direct mount design will create.
How many? Cause honestly if it's a handful, they need to rethink that whole flex stay decision and start handing out updated ones with bearing pivots.
Peak bending moment occurs at the axle end of the seat stay. This snapping is unrelated to the flex stay if it's happening at the linkage end. Looks like it's a compression failure in the tube that wouldn't be fixed by adding.the bearing.
Also given the brake mount location the actual angle change on the flex stay is negligible and the 6 bar description is more academic then actually measurable. That said I've not modelled the kinematic myself.
Is this the linkage end?
BK says why not have a light frame, not sure the warranty department will agree with him. Seems an odd goal to go for with a modern DH bike, sure make it not a tank, but weight weenies aren't buying DH bikes.
Yes this is the linkage end. That's where it snapped in Tasmania as I recall.
He snapped the chain stays and seat stays at hardline.
The picture above was at PDS rock creek
Last year's prototype Demo with a TTX22m.2 installed?
Tell us more.
https://cyclingmagazine.ca/mtb/specialized-finally-reveals-finn-iles-pr…
I didn't look at the image properly the first time - that's pretty catastrophic! Although fixable with a modified layup!
Who's bike was it?
just thought it was a good angle, better than i previously recall seeing.
I thought the wear marks in this pic were interesting
Your point is valid but I’d take it a step further and say hell no to a light bike due to safety. In my view, frame failures (especially DH bikes meant to hit huge features) are just as bad as helmet failures, full stop.
The Main DH bikes Weve seen in the media breaking have been marketed as light DH bikes, such as the gambler (team changed to the alloy one for a bit) and pivot - both carbon, i dont think its a carbon itself issue but more of a design and choice of layup thickness etc
personally my DH weighs upwards of 19kg with 500g weight under the BB. the things a rocket ship. as BK said, DH tracks are much faster these days and many of the Trek riders said not to make a carbon version of the HP session(this was in a media interview) as the weight and flex of alloy seems to make them go good.
The only time i've whinged about the weight of my bikes is putting them on my rack which is a non issue haha
Not really a tech rumour but a tech wish: since we’ve somewhat stabilized on geo development and are looking at new ways to innovate, can companies put more effort into silencing bikes? It’s kind of embarrassing that a $10k bike sounds like a shopping cart.
Baseball card holder tab on my seat stay so I can have a good sounding motorbicycle thing. Thats a industry standard we need.