[davep]

When is 'light' too light??

There were a few pics taken at one of the earlier world cups races that showed two seperate incidences of this same thing happening. Someone said that the rider was a tester and possibly the forks were not stock. I can totally see this as a possibility once, but twice?

and now ....

This photo is from the Worlds.

Makes me think that maybe that magical minimum weight limit might have been reached.

Don't really mean for this to be a boxxer bash, more of a questioning of the 'super light weight at all costs' trend, and this fork is sort of a flagship for this movement.

Is it worth it for the average weekend racer to save a total of a pound or two and risk this kind of thing? Best case scenario, the part is warranteed and you are only without a ride for a couple of weeks to a couple of months . Wort case...the item was used outside of 'intended use' or 'abused' and you get to purchace a brand new part. And that 10% reduction in weight will cost you 50% more $$ that the 'heavier' part.


I am not saying we all should be on 50lb bikes. 40-42 lbs can build a bomb proof bike. There is a limit to material strength, and it seems like maybe that limit is being reached within the limit of 'realistic' bicycle pricing.

just a thought...

 

[Jimmy_Pop]

landing that jump the way he did was going to do one of two things: break the headtube off or break the fork.

Why would you expect a fork to take such a bad fvck up?

That's racing. buy a new fork. its not the forks fault IMO.

jh

 

[black noise]

A few years ago 40-42lbs was stupid light and that stuff failed too. We're contantly lowering the "minimum" weight limit, once in a while we cross the line. And besides, if you look at the pics of the crash, it's a 50-50 case at probably 30mph, I'd expect any fork to snap aside from a Monster.

 

[ThePriceSeliger]

There are pro freeriders riding the new forks, redbull rampage style, huge hits, and the forks arn't breaking. That was a cased jump at high speed, and I bet he is lucky to be walking away.

 

[bjanga]

I guess it all comes down to the severity of crashes we want our components to sustain.

 

[offtheedge]

i don't think that a coil sprung fork breaks in many of these situations. at least not in the manner I have seen the boxxers splitting lowers.

 

[Westy]

i don't think that a coil sprung fork breaks in many of these situations. at least not in the manner I have seen the boxxers splitting lowers.

And why would you say that?

 

[coma13]

i don't think that a coil sprung fork breaks in many of these situations. at least not in the manner I have seen the boxxers splitting lowers.

That's a ridiculous statement... So if he was riding a Boxxer Team would it not have split because of that serious structural member the spring?

 

[Jeremy R]

i don't think that a coil sprung fork breaks in many of these situations. at least not in the manner I have seen the boxxers splitting lowers.

It is ironic that the only pics I have seen like that of boxxers have all been 06 world cups. Don't get me wrong, all forks can break, and I have seen plenty of busted up boxxers before as well as other DH forks.
Maybe it was just a coincidence, but it is strange to see the same fork snap at the same place like that.
It could be nothing though. Casing big gaps at pro race speeds, breaks parts. Constantly.

 

[Downhiller]

put more pics like those

 

[coma13]

It is ironic that the only pics I have seen like that of boxxers have all been 06 world cups. Don't get me wrong, all forks can break, and I have seen plenty of busted up boxxers before as well as other DH forks.
Maybe it was just a coincidence, but it is strange to see the same fork snap at the same place like that.
It could be nothing though. Casing big gaps at pro race speeds, breaks parts. Constantly.

Also in consideration of this... the people who are casing gaps at high speeds are pro racers and they're more often than not on Boxxers this year... (or Fox 40's but we don't need to get into that...)

 

[profro]

This year alone, I've seen:

WC Boxxers with broken lower castings
Fox 40s with broken brake arches
Manitou Travis' with blow cartridges

I haven't seen any broken 888 since the leaky castings a few years ago.

Everything breaks

 

[davep]

Ok since everyone is making this about this particular fork, which was not the idea (as stated).

In all of the world cup and norba pics that I have seen this season posted all over the web, I have seen exactly three broken forks. All three were the same make and model! All broke in exactly the same way. Anyone seen a catastophic failure of a fork from a different vendor this year?
I am not going to argue that that fork should have made that crash, I was not there and neither were any of you!! Arguements about the riders velocity and the results on 'all forks' are without merit.

This is a world cup race product and used as such. Why should one expect it to break and not expect a warranty?? It is NOT sold as a 'race only' item with no warrantty.

If your near new TV stopped working while watching TV (its designated use), should you just buck up and buy a new TV, or car, or piece of furnature, or anything else sold with a warranty and used as intended?






OK back to the original question..are high end bike parts lacking realistic durability in favor of light weight??

 

[jonKranked]

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.

 

[offtheedge]

That's a ridiculous statement... So if he was riding a Boxxer Team would it not have split because of that serious structural member the spring?

Easy reverend, come down from the pulpit and relax. I said “I think", not I know or this is what it is.
You don't think a 500lb spring is a structural component in a fork? You don’t think that a spring will absorb anymore of the lateral forces than an air cartridge?
Have you seen one coil sprung fork snapped like this?

 

[Zutroy]

That looks like Dez from NZ that rides for ODI, it's more than likely a stock WC unless someone hooked him up. That was a hard ass hit it looks like

 

[davep]

JeremyR exactly my point

downhiller search RM for post of pics at an earlier world cup. I cant remember which race sorry.

 

[binary visions]

You don't think a 500lb spring is a structural component in a fork? You don’t think that a spring will absorb anymore of the lateral forces than an air cartridge?
Have you seen one coil sprung fork snapped like this?

You aren't putting a 500lb. spring in a fork. In a 7" fork, you'd be up to 2500 lbs. of force to compress the last inch. The rules that apply to a rear shock, which has a leverage ratio on it, are not the same for forks. Have you ever seen the spring inside a fork? They're not all that stiff.

The springs in forks are not absorbing lateral forces in a fork, at least not any significantly measurable ones. A spring would not have saved that fork.

 

[frznnomad]

originally posted by offtheedge i don't think that a coil sprung fork breaks in many of these situations. at least not in the manner I have seen the boxxers splitting lowers.

ive seen a slider dc break in two on the lowers a few years back. just because it has a spring instead of an air chamber doesnt mean its necessarily a stronger fork. i think the boxxers are extremely durable (especailly for a first gen air fork) and if you would case a gap like that running 30+ mph im sure your fork, spring or air, would do the same thing.

 

[davep]

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.

Did you just get a new job @ R.S. in the marketing dept.??

 

[jonKranked]

nope. some basic numbers derived on common sense. the percentage is waaaay high though - i based it on 300 BCW's propduced, which is definitely a low ball park estimate.

 

[offtheedge]

You aren't putting a 500lb. spring in a fork. In a 7" fork, you'd be up to 2500 lbs. of force to compress the last inch. The rules that apply to a rear shock, which has a leverage ratio on it, are not the same for forks.

The springs in forks are not absorbing lateral forces in a fork, at least not any significantly measurable ones. A spring would not have saved that fork.

alright the spring rate was way off, but my point is the spring does absorb lateral force and the significance of that is relative, so again have we seen any boxxer teams or races broken like this? I'm assuming they use the same loweres on all models.

You may be right that nothing would have saved that fork, but i'm sure cases like this one have been ridden away from many times.

 

[jonKranked]

my point is the spring does absorb lateral force

no no no no no. NO! Have you ever even seen the insides of a fork?

 

[binary visions]

davep, your argument about televisions is not applicable.

The fork is made to go down hills and absorb bumps. It is not made to 50/50 case a landing or to take a 35mph impact into a tree.

A more valid comparison would be, you bought a Honda Civic. You decided you'd enter it into an autocross event and broke it. Should the manufacturer warranty it? Nope. You can get your warranty if you drive it like a regular person. Your warranty doesn't apply if you drive it into a tree or take it racing.

In response to the original question, no, I don't think the lower limit has been reached. Not even close. There will always be people who want lightweight at all costs. If it'll survive a single race run, 95% of the time, then they want it. That includes pros and consumers alike.

 

[offtheedge]

many times..rebuild them regularly

 

[binary visions]

the spring does absorb lateral force

No, it doesn't. Period. The lateral force goes into the bushings and the stanctions where they overlap (mostly), and the cartridge rod. The springs are not relieving this stress to any measurable extent.

have we seen any boxxer teams or races broken like this?

Correlation does not equal causation. Just because you haven't seen a Team or a Race fork break like this, doesn't mean they won't. It just means they haven't or you haven't seen it. How many of these World Cups have you seen break like this? Two or three? That's not a significant number.

 

[jonKranked]

many times..rebuild them regularly

then what kind of logic are you using to base this argument? springs in a fork absorb force in a vector parallel to the stanchions, not perpendicular to it. any lateral force absorbed by the springs is insignificant and would have had no impact on the failure of that kind of impact.

 

[davep]

Therea re a couple things wrong with the 30mph claim that everyone keeps making up. First of all if he was traveling at 30mph, he would have most likely overshot the landing, not come up short. Find a profile shot of the jump and you can figure the trajectory. Second, if he hit the landing @ 30mph, his momentum would have most likely carried him 'through' the landing lip. Looks like he went way to slow and kind of stalled in the air. The way that he came down, it looks like the fork took all of his weight, perpendicular to the fork compresssion direction.

Again not arguing that this or any fork should have lasted, but why is it this particular fork that this happens to?

 

[jonKranked]

Again not arguing that this or any fork should have lasted, but why is it this particular fork that this happens to?

i've said it before in this thread, just look.

RS boxxers are well known to have paper thin walls on the lower slider.

 

[sanjuro]

Ok since everyone is making this about this particular fork, which was not the idea (as stated).

In all of the world cup and norba pics that I have seen this season posted all over the web, I have seen exactly three broken forks. All three were the same make and model! All broke in exactly the same way. Anyone seen a catastophic failure of a fork from a different vendor this year?
I am not going to argue that that fork should have made that crash, I was not there and neither were any of you!! Arguements about the riders velocity and the results on 'all forks' are without merit.

This is a world cup race product and used as such. Why should one expect it to break and not expect a warranty?? It is NOT sold as a 'race only' item with no warrantty.

If your near new TV stopped working while watching TV (its designated use), should you just buck up and buy a new TV, or car, or piece of furnature, or anything else sold with a warranty and used as intended?

OK back to the original question..are high end bike parts lacking realistic durability in favor of light weight??

Forks is not TVs. The comparison would be more like car tires. Any failure for almost any driving condition which did not puncture the tires would be cause for a recall.

Now, I doubt the Boxxer broke while JRA, but it looks bad to the average customer (that would be me) when I see that. I understand the concept of "Black Box", but I have to weigh reliability and safety over any performance gain because I don't compete.

 

[offtheedge]

then what kind of logic are you using to base this argument? springs in a fork absorb force in a vector parallel to the stanchions, not perpendicular to it. any lateral force absorbed by the springs is insignificant and would have had no impact on the failure of that kind of impact.

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?
I'm not saying that a coil would have saved any fork from breaking. I'm not saying that a coil in compression produces a linear force strong enough to counter the lateral forces at any significant level.

I haven't seen ANY fork break like this , and sure correlation doesn't justify causation, but the facts are no body has any other reasoning for this model of fork to be breaking. Riders have been casing jumps at 30 mph for a long time.

 

[offtheedge]

i've said it before in this thread, just look.

RS boxxers are well known to have paper thin walls on the lower slider.

and are those not the same lowers on the other models?

 

[coma13]

Therea re a couple things wrong with the 30mph claim that everyone keeps making up. First of all if he was traveling at 30mph, he would have most likely overshot the landing, not come up short. Find a profile shot of the jump and you can figure the trajectory. Second, if he hit the landing @ 30mph, his momentum would have most likely carried him 'through' the landing lip. Looks like he went way to slow and kind of stalled in the air. The way that he came down, it looks like the fork took all of his weight, perpendicular to the fork compresssion direction.

Again not arguing that this or any fork should have lasted, but why is it this particular fork that this happens to?

Take a look at the first picture... Do you see how far his wheel is stuffed laterally into the landing? That doesn't happen from going slow and stalling out in the air... Without seeing a whole sequence or video there really is no way of knowing but he could have sucked up the lip too much and just not gotten the altitude he needed to get on top of the landing and when he saw he was going to case it he stood it up, smacking the back tire into the face and then slapping down the front end super hard due to the speed he was moving at.

 

[jonKranked]

Have you seen a coil sprung boxxer break like this?

do you see anyone on the world cup circuit racing a boxxer other than the world cup?

 

[A.P]

To whoever said that the team's lowers are more durable then the WC lowers is wrong. They both have identical lowers, and there is NO way a spring can contribute any lateral stiffness to the fork. Have you ever felt an 8'' boxxer spring? you can bend them 180 degrees and they just flop everywhere. If anything the air piston would add "stiffness" over the spring, but the flex of a fork has to do with the bushings and crowns anyway, not the spring.

Boxxer lowers arent that strong, and they have never been that strong. But they generally dont break or bend unless you really crash hard. This year in the group of people I ride with there have been 4 different sets of lowers either bending significantly, cracking, or both, 2 under the same dude and 2 from 2 different people. All of them were in serious crashes, mostly in open slope rock stuff. Keep in mind that in some of these crashes wheels were taco'd, frames were dented and other stuff exploded too. They werent from just riding along.

They arent that expensive to replace lowers either, so deal.

 

[Tame Ape]

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?
I'm not saying that a coil would have saved any fork from breaking. I'm not saying that a coil in compression produces a linear force strong enough to counter the lateral forces at any significant level.

I haven't seen ANY fork break like this , and sure correlation doesn't justify causation, but the facts are no body has any other reasoning for this model of fork to be breaking. Riders have been casing jumps at 30 mph for a long time.

Please stop your rampant cluelessness before someone gets hurt! Think of the children!!

 

[offtheedge]

Please stop your rampant cluelessness before someone gets hurt! Think of the children!!

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?

 

[Cant Climb]

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....

 

[jonKranked]

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....

aaaaaaand that's why i didn't get a BWC

 

[seismic]

Just happy I dont ride a boxxer...