Fox 38
- Thread starter jonKranked
- Start date
See. It’s already starting.
didn't they do a dual crown domain for a while? but 35mm stanchions, I think . . .
YESYESYESYES . . . YES
Its actually useful though and I'd guess that that style of quick release has less chance of inducing any sort of binding, compared to other styles that screw in from one side and squeeze everything together.
I want it because my bike lives in the back of my car, so every time I go anywhere I have to take the front wheel off.
^^^ canadmos is on the money
The awesome thing about the original Fox 20mm axles (which date right back to 2004 when the first Fox 40 prototype came out, complete with CNC machined 3-piece bonded lowers and a triplet of compression adjusters, low/medium/high) is that they don't clamp the lower legs together when you do the axle up, which makes a very significant difference to friction. They used this design for the 20mm axles on all 36 and 40 (still do on the 40).
It doesn't matter how stiff your enduro-punter "stiffer than a 36" Lyrik is, it still has the same joke axle design as every other 15mm fork (including the current joke-axled 36), in that it depends on hub width and droput precision to define parallelism.
Also, a 40 is an example of an actual stiff fork, a singlecrown is not.
The awesome thing about the original Fox 20mm axles (which date right back to 2004 when the first Fox 40 prototype came out, complete with CNC machined 3-piece bonded lowers and a triplet of compression adjusters, low/medium/high) is that they don't clamp the lower legs together when you do the axle up, which makes a very significant difference to friction. They used this design for the 20mm axles on all 36 and 40 (still do on the 40).
It doesn't matter how stiff your enduro-punter "stiffer than a 36" Lyrik is, it still has the same joke axle design as every other 15mm fork (including the current joke-axled 36), in that it depends on hub width and droput precision to define parallelism.
Also, a 40 is an example of an actual stiff fork, a singlecrown is not.
Absolutely true, but (greater) stiffness is far more important in a fork than a frame, as alongside the front wheel and handlebar, it literally defines your trajectory.
My comment was directed at Happymtb.fr, if you ride something like a 35 Boxxer and compare to a 40 in demanding terrain (particularly rough and steep tracks where there there is high force driving the wheel down into the ruts), the 40 is noticeably easier to keep pointed where you need it to go. I've owned multiples of both, and the difference is most noticeable when you switch back to the 35 from the 40.
I don't think any singlecrowns with 15mm axles are actually at a level where compliance needs to be introduced in any particular area, if anything the modern singlecrown has some way to go to be sufficient for what some of their harder owners are putting them through.
Not sure which years you compare, but from memory the newer 40s are less or similar stiff as the previous generation Boxxer. Only found the below data from '14. Guess you have to Rux it now! 
Source: http://www.freeride-magazine.com/test/dowhnhill-gabel-dvo-emerald-im-exklusiv-test/a23155.html
Source: http://www.freeride-magazine.com/test/dowhnhill-gabel-dvo-emerald-im-exklusiv-test/a23155.html
Someone always brings this up. I think it's absolute BS for MTB. No one is ever saying "oh, I can't ride this hardtail, it's too laterally stiff!". Literally every FS bike is trying to be as stiff as possible in that direction and it's hard with pivots and the inherent flex they create. Laterally stiff rides off-camber better, holds lines better, delivers your pedaling power better, etc. Although there are certainly small areas on a car chassis where they try to design in some compliance/flex, the big improvements are always when they increase the chassis rigidity, boosting another 30% or whatever to make it more rigid and it will hold the road better. Not to be confused with suspension too stiff without enough wheel travel that may skip and slide on normal streets vs. smooth tracks.
There are areas that simply can't be too-stiff on a bike. Fore-aft on the fork is one of them, lateral on the FS frame is another. I think we have a little more of a sweet-spot for torsion on the fork. Maybe there's some ultra-apex of frame stiffness that we will eventually achieve that is "too much", but until then, I need something that can ride those off-camber lines as well as my rigid bikes, or at least as well as possible.
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The stiffness thing for motorcycles is a totally different scenario, where bike/rider/tire/track conditions allow for crazy lean angles. Yes, when leaned over at 55 degrees hitting a bump that's therefore 55 degrees to the up-down motion of the wheel might be bad if there's not lateral compliance.
That scenario doesn't happen in my riding at least. Maybe I'm not endurbroing hard enough.
That scenario doesn't happen in my riding at least. Maybe I'm not endurbroing hard enough.
It's true, that's why dh frames always use thinner tubing, and have tighter spaced bracing. It's also why dh wheels always weigh less, flex more and are build with much thinner and lighter rims. It also explains the prevalence of single crown forks in dh instead of those silly dual crowns which just make them unrideable.
Cornering hundreds of horsepower on pavement is pretty much a direct parallel to smashing off camber rocks and irregular dirt at 23mph.
Good that you know it better than people like Nico Vouilloz. I remember an interview with him where he explained that the right stiffness is needed to go fast, so e.g. super stiff wheels are detrimental to run times. But I guess the lizards solved this problem by going 29".
For me I found that I have to match the components to have similar flex, so not mixing a flexible frame with super stiff wheels. This feels unpredictable and awkward to ride to me. I prefer more "flexy" parts (Dorado over Idylle, old Boxxer over old 40) as they seem to result in me riding better and faster.
Ahem, 29-er DH bikes. I rest my case.
I was soooo close before when I learned that you now embrace the wrong wheel size. But for entertainment reasons, no!
I would have deserved it. between my dh bike and trail bike I have 1 pair of 27.5 wheels and 3 pairs of 26s that get rotated around.I was soooo close before when I learned that you now embrace the wrong wheel size. But for entertainment reasons, no!
He is the Alien, after all!
Nevertheless, besides him there are plenty of examples for this:
Syndicate reducing spoke tension because wheels were too stiff.
Bouwmeester wheels.
Athertons cutting the cross brace on their Commencal DH bikes' rear stays.
Klausmann reducing spoke tension for compliance.
Mavic
etc.
I am not saying that frames, forks and wheels should be flexy, they should have the right flex to aid traction. I am not riding at Worldcup speeds and I am not exactly a clyde, so maybe I can get away with more flex than these folks in order to make the bike ride right for me?
Well at least you picked two photos that actually do relate somewhat to road racing.
The bikes sucked and, the courses sucked back then. The fact that you and I just posted 3 photos of dirt roads shows how little that era (and yes, even that person) has to do with going fast on bikes in the woods these days.
Even more impressive at what speeds they rode then. Not so sure about the courses sucking though. They were longer, had super fast parts but some were still technical (Grouse, Nevegal, Cap d'Ail). And it is not like we have no dirt roads these days, they are just called "motorways" or "bike park bits" (Leogang, Fort William).
But I agree with you, the sport has changed. Not sure if for the better though, considering all the 29ers raced these days.
But I agree with you, the sport has changed. Not sure if for the better though, considering all the 29ers raced these days.
And just as many of us that are reveling in the stiff-wheel revolution that can finally hold lines under hard-G conditions that we've never been able to. It seems the only people really complaining about this are running hardtails...well, that's their own damn fault for running hardtails. If anything, it's a damping problem for the shocks to handle, not that my wheel should go oval on every impact-problem.
Unless I experience something radically different in the coming years, I will keep going for the stiffest frames, that's one of the best things about my Pivot.
There are plenty of FS frames out there that are too stiff in the wrong places.
Mark my words, someone in the bike industry will eventually hire a competent dynamicist and make some sense out of all of this with a bike that is built with balanced stiffnesses of every component from the tires to the grips to the taint-tapping seatposts we've all come to love. Specialized or Trek most likely.
So why has the GRIP2 damper fallen out of favor exactly? I have one in a fork that I did a damper update to from a RC2 cartridge or whatever it was, and I haven't really ridden it yet.
Mark my words, someone in the bike industry will eventually hire a competent dynamicist and make some sense out of all of this with a bike that is built with balanced stiffnesses of every component from the tires to the grips to the taint-tapping seatposts we've all come to love. Specialized or Trek most likely.
So why has the GRIP2 damper fallen out of favor exactly? I have one in a fork that I did a damper update to from a RC2 cartridge or whatever it was, and I haven't really ridden it yet.
But we are primary talking about lateral stiffness. To not get sucked downhill in off-camber situations, you need as much as you can get IME. My foes was ultiamtely stiff in all directions, but because of the dumbass curnut it always felt like it was about to snap in half, so damn harsh, but that was 100% the shock and bizarro single-pivot.
Deflection is often the result of a frame that’s too stiff. Chipping out or hopping the back tire in a drifty flat corner is usually due to a frame that’s too flexy. Lighter riders need less stiffness than heavier riders for the same dynamic flex. Too much rear end flex side loads bearings and shocks. Too much stiffness sucks as much as too much flex.
These are just my observations.
These are just my observations.
A friend of mine is a former MX pro and is now working as a full time development rider for a certain local manufacturer known for orange colorways. And from his stories the thing they are tinkering the most after shock and suspension layout is stiffness of the frame and the swingarm. Max stiffness is not the ultimate goal it seems.
EVERY moto manufacturers factory team is playing games with frame stiffness and engine mount/swingarm torques. Even the satellite teams are. Hell, even I do before a race. I tighten everything down on the chassis to the nominal torque minus 5% or 10% depending on what speed race I'm doing, and it will be a more radical difference than a fresh suspension servicing. You'll see teams machining off 1/8" sections from the rear side of their upper triple clamps as well. Again, a difference in feel that isn't trivial.
Every few years, the DOT and CPSC standards go up for motorcycles. So the frames have to become stiffer and more resilient for front-end impact load cases. This makes the ride quality suck sweaty ass. It becomes a game of trading off compliance and comfort on very small inputs with ultimate strength/failing load for that front end impact.
Short version - nobody in the motocross game is trying to increase stiffness anywhere in the chassis these days, with the exception of swingarm torsional stiffness, usually to handle powertrain torque.
Oooh harsh, then again I do seem to be one of the few on here that like the Flow Mk3, I like the noodly nature of them.
Some reading here about low spoke count/light weight spoking of carbon wheels-
Nox Composites
Our carbon rims provide a very high level of rim stiffness, so much so that they can literally overpower low spoke stiffness and this can actually amplify lateral deflection at parts of the rim away from the lateral loading point (the ground). In other words, with all other things equal, carbon rims can increase the rubbing against your chainstays, fork or cantilever brakes!
Udi, I agree with you that a dual crown fork will feel stiffer, more secure, less on the edge than a single crown in rough situations. This thread is about the Fox 38 which seems to be marketed as an enduro fork, I therefore compared it to its direct single crown equivalent from RS. My comment about the Boxxer having 35mm stanchion was in no way meant to imply that the Boxxer is stiffer than the 40.
Great that I am not the only one. Thank you!
But it is, see above graph I posted.
Ok, interesting! It would be nice to have these numbers for more recent versions.But it is, see above graph I posted.
Having actually ridden/owned plenty of Boxxers and 40s (including current), I reckon those test results are about as accurate as Enduro MTB's "brake dyno" results test. Writing some numbers down and making a pretty graph doesn't actually mean the data is correct.
@slimshady could you elaborate?
@buckoW agrees but I doubt he'll post his reasons, for fear of getting devoured by the enduro punter nation.
I'm not sure of the exact reason/s myself (curious) but Ryan @ Vorsprung commented a while ago that the damper actually had more friction than the last RC2 (though Fox claim less), and a few quicker riders I know have switched back to the RC2 also.
@slimshady could you elaborate?
@buckoW agrees but I doubt he'll post his reasons, for fear of getting devoured by the enduro punter nation.
Also, you know this place is getting bad when I agree with every single post @kidwoo has made.
@jstuhlman mommy and daddy are getting back together, gonna dress you up in a nice little suit for the renewal of vows.
@jstuhlman mommy and daddy are getting back together, gonna dress you up in a nice little suit for the renewal of vows.