[binary visions]

my logic, which you have turned into an arguement is one that you have yet to answer.
Have you seen a coil sprung boxxer break like this<snip>
Riders have been casing jumps at 30 mph for a long time.

I have seen a couple of these forks break in this fashion. Both of them have been on pro's bikes. Please find out for me how many pros are running the Team or the Race version of the Boxxers.

That's not logic. You're taking an arbitrary reason that you think these forks might not be breaking, and making a correlation by saying that, out of a tiny number of forks that have broken like this, none of them have been coil sprung.

I have seen a lot of Subarus break. The Subarus I have seen break have had 4 cylinder engines. My theory is that 6 cylinder engines impart less stress on the engine components because I have not seen a 6 cylinder Subaru break.



But wait, my family has owned half a dozen 4 cylinder Subarus and not one 6 cylinder. The only 6 cylinder Subaru I know of is driven by a 60 year old man. Think that has something to do with it instead?

 

[Tame Ape]

wow! your use of rampant was impressive, so now that we know you have a dictionary at hand do you have any relative information to add?

No, not really other then you should know that Binary Visions really does deserve his title and that his explanations are worth taking seriously.

Incidentally the proper word is 'relevant' not 'relative'.

 

[offtheedge]

When Marzochi's 888 air comes out, there will finally be light racey DH fork that will be able to handle a ton of abuse for multiple seasons....

there is........dh40

 

[bjanga]

offtheedge, how would a spring make the fork stronger?

I would guess that the fork snapped before compressing much (if any) into its travel.

 

[jonKranked]

there is........dh40

still not as durable as marz. my buddy races a 40 and the slider on his looks like the cellulose on a fat womans thighs. tons of dents everywhere.

 

[coma13]

still not as durable as marz. my buddy races a 40 and the slider on his looks like the cellulite on a fat womans thighs. tons of dents everywhere.

unless her thighs were covered with sawdust or something...

 

[jonKranked]

sorry. i don't do research on fat people like you obviously do. Thanks dictionary police. And it probably wouldn't hurt some fatties to get covered in sawdust... then burned. It would smell horrible though.

 

[skinny mike]

after reading this thread i have come to the conclusion that only BV has taken or retained anything from a statistics class. 3 broken world cups means exactly nothing statistically. now if we had seen 20 or 30 world cups break in exactly the same way then we might be onto something about the fork.

 

[bjanga]

Thats why we are trying to talk about lightweight components overall.
I am curious to know: Do you think your componentry should be able to stand up to something like that?

30mph, 15mph, tough to say. I wonder how messed up his rear wheel is.

 

[jonKranked]

after reading this thread i have come to the conclusion that only BV has taken or retained anything from a statistics class. 3 broken world cups means exactly nothing statistically. now if we had seen 20 or 30 world cups break in exactly the same way then we might be onto something about the fork.

read the thread eh?

For the record, RS Boxxer's have had notoriously thin walls on the lowers for years. This is nothing new. These forks that are breaking in this manner are being ridden to their limits by the most elite downhillers in the world. Not surprising, sh!t breaks at that level of competetiveness. And I've seen a grand total of 2 or 3 of these style breakages ALL YEAR. out of how many boxxers that have been producded? these failures constitute less than 1% of the BWC market and should not be taken as representative of their quality.

 

[coma13]

sorry. i don't do research on fat people like you obviously do. Thanks dictionary police. And it probably wouldn't hurt some fatties to get covered in sawdust... then burned. It would smell horrible though.

hahaha yeah, i'm working on my thesis right now. What do you think of my tentative title:

Wooden Fatty Spelling Bee:
A discourse on the dissimilarities of cellulose and cellulite.

 

[Zutroy]

Thats why we are trying to talk about lightweight components overall.
I am curious to know: Do you think your componentry should be able to stand up to something like that?

30mph, 15mph, tough to say. I wonder how messed up his rear wheel is.

The wheels look straight in the pics. That's some good sturdy wheel building there.

 

[Cant Climb]

after reading this thread i have come to the conclusion that only BV has taken or retained anything from a statistics class. 3 broken world cups means exactly nothing statistically. now if we had seen 20 or 30 world cups break in exactly the same way then we might be onto something about the fork.

Fact is some of them have snapped. Most DH'rs want to be 100% confident there stuff isn't going to catastrophically fail......

 

[jonKranked]

hahaha yeah, i'm working on my thesis right now. What do you think of my tentative title:

Wooden Fatty Spelling Bee:
A discourse on the dissimilarities of cellulose and cellulite.

oh how i miss repuation and approval

 

[offtheedge]

No, not really other then you should know that Binary Visions really does deserve his title and that his explanations are worth taking seriously.

Incidentally the proper word is 'relevant' not 'relative'.

thanks for that, and I'm not questioning BV or what he says, but as with 99% of these threads it's impossible to just discuss possible causations without monkeys chiming in calling people out just because they only want to hear one side. I could give a rats a** what fork breaks where. I have no product loyalty beyond wanting what I bought to work.

as i asked a couple times, if air or coil makes no difference in the structural integrity of the fork why haven't I seen a coil sprung break the same way?

that's a question, not a stab at air sprung forks.

 

[dropmachine]

One thing I've noticed is that in all the pics, the riders seem no worse for the wear.

FOrks break, deal with it.

 

[jonKranked]

as i asked a couple times, if air or coil makes no difference in the structural integrity of the fork why haven't I seen a coil sprung break the same way?

marzocchi, manitou, and fox all make their forks strong enough. Anyone riding a RS product hard enough to break it in that manner is at a level that they aren't paying for their own fork (hence the WC and not the team or ride), or they can afford to have it fixed immediately.

 

[offtheedge]

still not as durable as marz. my buddy races a 40 and the slider on his looks like the cellulose on a fat womans thighs. tons of dents everywhere.

which lends to the original topic, weight versus durability and
unfortunately thinner is the easiest path to lighter.

 

[bjanga]

For the record, RS Boxxer's have had notoriously thin walls on the lowers for years

What constitutes 'notoriously thin'? What do wall thicknesses look like for the 888 Travis 40 and BWC? Why does the totem have bulged lowers?

The wheels look straight in the pics. That's some good sturdy wheel building there.

Or just too-lightweight lowers?

why haven't I seen a coil sprung break the same way?

Not enough people are casing pondgaps.

 

[vitox]

offtheedge:
sorry man but you are way wrong assuming the spring had anything to do with it, ill prove you wrong first and then move on to the real argument which is pretty interesting.
if you have disassembled a RS boxxer, you would have noted that the spring is not rigidly attached to the forks structure, in other words, its "non structural". but EVEN IF IT WAS, what would it do, those springs are not like a shock spring that you cant bend sideways, a fork spring you can bend as you wish with your bare hands.
if the coil sprung fork was to have ANY structural advantage over an air sprung fork, it would be not because of the spring itself but beacuse of a possible control rod going inside the spring, like on a HSCV marzocchi for instance, (it doesnt add any structure but just for arguments sake...), but then again, the boxxer WC in question HAS AN AIR TUBE INSIDE, that goes further up the inner than the spring plunger who only goes to the bottom of the stanchion.
so, if anything, the WC boxxer is firmer than the team boxxer because of this.
then again, its clearly not relevant, because anytime the innards of a fork get used for structure, it means that the real structure is destroyed and anything that can destroy the outer structure thats several times wider (and therefore several times - squared, more rigid) will inevitably bend and destroy the puny dampers and plungers you find inside a fork.

now, for the real discussion:
the reason for these things happening i pointed out in my 2005 boxxer autopsy thread, its quite simple.
you see, RS didnt do much more than lengthen the travel on the forks, they didnt redesign the legs, and the result is the bare minimum of bushing overlap, its under 6 inches. they knew this would be pushing it and specced some GARGANTUAN lower and upper bushings to try and compensate, result is not bad, but it means more flex as the stanchion is supported on a smaller base and also more wear and longer break in period (those long bushings you know). also, remember the boxxer is the "skinniest" of the major dh forks (32mm vs 34mm for travis and 35 for 888 and of course 40 for the 40) and this also contributes as flex makes it easier for the structure to bind and not compress at all like you can see in those pictures.
bottom line is i think these cases of broken boxxers tell us the limit hasnt been crossed in terms of "too light" but its close, this is after all the worlds and if nothing failed i think most people would be riding things way overbuilt, BUT, the line is pretty close.

 

[jonKranked]

the materials to make a fork durable enough at that weight are cost inhibitive to produce. unless you wanna see an msrp of $3000+ for a fork.


marzocchi's are virtually bomb proof. i have never seen nor heard of a catastrophic failure of a marzocchi fork that was properly cared for (even improperly cared for forks). are they heavy? yes. can you beat the piss out of them for multiple seasons and not have a problem? yes. your average dh/fr rider will put up with the weight for durability. entry to sport, hell even some expert racers too. its more about budget, not many riders can afford a new fork twice a season.

 

[jonKranked]

What constitutes 'notoriously thin'? What do wall thicknesses look like for the 888 Travis 40 and BWC? Why does the totem have bulged lowers?

its not unheard of for older model boxxers to scrape open and start leaking fluid. i've seen plenty of people with plastic gaurds on lowers to protect against this.

 

[Tame Ape]

thanks for that, and I'm not questioning BV or what he says, but as with 99% of these threads it's impossible to just discuss possible causations without monkeys chiming in calling people out just because they only want to hear one side. I could give a rats a** what fork breaks where. I have no product loyalty beyond wanting what I bought to work.

as i asked a couple times, if air or coil makes no difference in the structural integrity of the fork why haven't I seen a coil sprung break the same way?

that's a question, not a stab at air sprung forks.

The Boxxer chasis probably isn't significantly different between the spring or air models. If you haven't seen crushed coil spring forks, its probably because no one's bothered to take a recent picture. People have converted coil forks to air springs in the past without issue, its not a structural thing. Look at Mojo Uk for example, they pull all the guts and from both legs and put custom internals back in. In ONE leg.

 

[elRey]

I have seen two broken boxxers in person this season. One was at a race and one was at the local trails. And I have seen more than a couple online. I have yet to see a broken 40 or 888 in person. Also, all the rockshox that I see break, break in the EXACT same spot.

 

[offtheedge]

vitox:
you said what is probably the single biggest factor.....32mm stanchions. same principle as a one-point-five HT. the bigger the stanchion, the more contact surface, the stiffer bushing interface will be. I bet these boxxers break once the stanchions teeter in the bushing causing the bottom of the stanchion(s) to make contact with the inside of the lowers at a point of extreme tension, crease, split, break.

 

[davetrump]

**edit... pardon the spelling and gramar mistakes, i typed to quickly and am too lazy to fix**

i think we have established that the air vs. coil had nothing to do with it... but no one has mentioned the style in which he jump was cased and how that played into it

when you case a jump this bad with the rear wheel on the back side and fron wheel on the downside your front wheel, fork, head tube are under a TON of stress... the fork will not compress at all since it is being hit from the back (perpendicular to the directione the foork travels)... it would be like having dropping to flat with a 30 degree head angle (like a chopper for instance), you would get no compression at all to absord the energy/impact/stress whatever you want to call it. there is a ton of leverage between the bottom crown and the axle, and the weakest point is what will give... which on a conventional fork (non inverted) is where the bottom bushing ends.... if the fork had compressed than the damping rods would not be bent in the fasion they are in these photos (completely extended)

most times you case and momentum saves you, or you flip over etc... this guys crash is a lot les common where you land front wheel way high and stuff the rear wheel so hard that you are no longer moving forward, and the result is a very hard slam to the front end (on an agle that prevents the fork from compressing, and is basicaly trying to rip your bike in half)

think about it for a second and try and say that ANY fork that takes a crash like that you not at least bend or crack in the same place just below the bottom bushing... or worse yet rip the headtube off if the frame was crap

32mm stanchions have nothing to do with it... if they were not strong enough they would have bent/broken at the bottom crown... offthe edge, the stachions to not "teeter in the bushings cuasiong the bottom of the stachion to contact the inside of the lowers"... there are two huge bushings in all forks, and it is imposible for the stanchions to flex into the lowers (unless the fork is already bent/broken)... this fork never even got a chance to compress, the angle it hit the ground made it unable to compress, and broke the fork off just below the lower bushing, which is the weakest point in this kind of impact.

alos... the other set of pics of a boxxer broken like this was from willigen world cup (the one with the HUGE jumps that very few riders were clearing with ease)... that fork also broke from 50/50ing a step up where one whell was way down the back side while the fork was on the down side

so two fork broke in the same spot at the world cup level from rider error on big high spped jumps.... yeah, must be something wrong with the fork

by the way, rockshox has not changed the lowers from 05 to 06, and they are the same lowers used in every boxxer... ever think it is an isolated incedent that comes from the highest levels of competition?

 

[SilentJ]

think about it for a second and try and say that ANY fork that takes a crash like that you not at least bend or crack in the same place just below the bottom bushing... or worse yet rip the headtube off if the frame was crap

I tried casing a jump like that once...02 Monster held up and the Canfield held up. Surprisingly (and thankfully), the front wheel was the weakest link and folded in half like a two bit whore. Had my wheel not folded, I'm not sure what would have went...a guy in Third Down cased a pretty good gap and I think he broke his Monster stanchions right below the lower crown.

everything else..

For teh win!

 

[Downhiller]

boxxer..
this is to common to see..

fox

rare but this happens to

ps. dont know but every time i saw boxxer i love more and more my shiver :love:

 

[Orfen]

fox

rare but this happens to

not as rare as you might think...

this thread is pure e-comedy. DH stuff breaks folks - get over it.

 

[vitox]

32mm stanchions have nothing to do with it... if they were not strong enough they would have bent/broken at the bottom crown... offthe edge, the stachions to not "teeter in the bushings cuasiong the bottom of the stachion to contact the inside of the lowers"... there are two huge bushings in all forks, and it is imposible for the stanchions to flex into the lowers (unless the fork is already bent/broken)... this fork never even got a chance to compress, the angle it hit the ground made it unable to compress, and broke the fork off just below the lower bushing, which is the weakest point in this kind of impact.


by the way, rockshox has not changed the lowers from 05 to 06, and they are the same lowers used in every boxxer... ever think it is an isolated incedent that comes from the highest levels of competition?

its still has to do with the 32mm platform, it will always be a factor, unless you are thinking about a theorical case (just as flipping a coin and having it land on the edge) where there is no vertical component of force exerted on the fork, there always will be some force compressing the fork, the only way for that not to happen would be for the bike to land upright but somehow not touching the rearwheel first. probably some more cases too but equally nonrealistic.
this means that flex will always be a factor, so, stanchion diameter will also always matter.

anyway, its a moot point. the fork broke in an extreme racing situation, no news here.

 

[davep]

... Do you see how far his wheel is stuffed laterally into the landing?

Soft dirt.

 

[seismic]

Well, despite the weight of a freight train I can say that I am very happy with my Avalanche MTN fork.

 

[Downhiller]

not as rare as you might think....

god damn i was thinking that fox is strong fork and stif but those pics are just :hot: :hot:

damn

any pics of broken shivers or dorados or AVYs ?!?!

i mean inverted forks??

 

[SilentJ]

In defense of the dropout pic, I'm pretty sure someone needs to pick up a torque wrench.

 

[toodles]

oh... my... god...

Some of the comments in this thread border on ridiculous. I didn't know pictures of broken components posted on Pinkbike could be used for material shear strength analysis. Hell, if we could get them to post up pics of titanium sheeting my company could save thousands.

Seriously - why are these riders on Boxxers? Because they chose them or bought them, based on their research into the fork and their preference in feel. To the Boxxer haters - ever seen a set of 888s break? I have - guess that means you better run some Monster Ts. Oh wait, I've seen those break too, better play it safe and run some XR80 forks instead.

Speccing your bike is about making a trade-off between cost, strength, performance and weight. If you're not smooth enough to run light weight parts, or you have a tendency to run into trees at 30mph then yeah maybe spec your bike to be a bit more durable instead of going for the performance gains of lightweight components.

It is really that simple. Are WC Boxxers the strongest DH fork? No, not likely. But they are the lightest, and the performance gain from that is worth the trade-off in strength for many racers. Hell 99% of Boxxers WC owners will never experience problems or breakages, but 100% of 888 owners will experience heavier weight.

 

[vibiker]

Manitou Travis' with blow cartridges

That's funny. I thought that they derived the name "Manitou" from Latin phrase, which means "fork that leaks alot".

 

[lovebunny]

Soft dirt.

it doesnt matter. you still have to be hauling ass to bury your wheel to the disk

 

[davep]

as i asked a couple times, if air or coil makes no difference in the structural integrity of the fork why haven't I seen a coil sprung break the same way?

that's a question, not a stab at air sprung forks.

Very simple answer. There are far fewer coil sprung boxxers (as a % vs air w.c. fork) ridden by people who are fast enought to have their picture taken.

 

[davep]

it doesnt matter. you still have to be hauling ass to bury your wheel to the disk

Not true. That jump was just recently built and that part of the landing is not ridden to pack the dirt, thus there could be a large % of air in the soil. Organic loamy soil can be very loose and airy (that is a sheep field)

 

[davep]

offtheedge:
sorry man but you are way wrong assuming the spring had anything to do with it, ill prove you wrong first and then move on to the real argument which is pretty interesting.
if you have disassembled a RS boxxer, you would have noted that the spring is not rigidly attached to the forks structure, in other words, its "non structural". but EVEN IF IT WAS, what would it do, those springs are not like a shock spring that you cant bend sideways, a fork spring you can bend as you wish with your bare hands.
if the coil sprung fork was to have ANY structural advantage over an air sprung fork, it would be not because of the spring itself but beacuse of a possible control rod going inside the spring, like on a HSCV marzocchi for instance, (it doesnt add any structure but just for arguments sake...), but then again, the boxxer WC in question HAS AN AIR TUBE INSIDE, that goes further up the inner than the spring plunger who only goes to the bottom of the stanchion.
so, if anything, the WC boxxer is firmer than the team boxxer because of this.
then again, its clearly not relevant, because anytime the innards of a fork get used for structure, it means that the real structure is destroyed and anything that can destroy the outer structure thats several times wider (and therefore several times - squared, more rigid) will inevitably bend and destroy the puny dampers and plungers you find inside a fork.

now, for the real discussion:
the reason for these things happening i pointed out in my 2005 boxxer autopsy thread, its quite simple.
you see, RS didnt do much more than lengthen the travel on the forks, they didnt redesign the legs, and the result is the bare minimum of bushing overlap, its under 6 inches. they knew this would be pushing it and specced some GARGANTUAN lower and upper bushings to try and compensate, result is not bad, but it means more flex as the stanchion is supported on a smaller base and also more wear and longer break in period (those long bushings you know). also, remember the boxxer is the "skinniest" of the major dh forks (32mm vs 34mm for travis and 35 for 888 and of course 40 for the 40) and this also contributes as flex makes it easier for the structure to bind and not compress at all like you can see in those pictures.
bottom line is i think these cases of broken boxxers tell us the limit hasnt been crossed in terms of "too light" but its close, this is after all the worlds and if nothing failed i think most people would be riding things way overbuilt, BUT, the line is pretty close.

Nice, well though out, articulate (in non-native language), facts (not emotions or feelings). I like the way you post.

I was thinking something similar about binding between the upper and lowers. Maybe longer stantions and lowers extended below the axle (like the travis) would help.