Cracked.

Motodave15
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Motodave15
Edited Date/Time 8/21/2013 9:59pm
Anybody seen anything like this before?

I'm seriously wondering how the hell something like this happens

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slipdog
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slipdog 8/21/2013 4:03pm
8/21/2013 4:03pm
Bad casting and/or too much nitrogen.
Tim507
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Tim507 8/21/2013 4:26pm
8/21/2013 4:26pm
slipdog wrote:
Bad casting and/or too much nitrogen.
Coupled with a big hit! Clearly the shock couldn't move the fluids fast enough in the dampening transfer...........
Crush
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Crush 8/21/2013 5:10pm
8/21/2013 5:10pm
Holy shit!!!

That's incredible... Obviously Deegan would have had a lot of massive hits, but still, that's amazing... Shows how much harder the pros are on their bikes

The Shop

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motokiwi
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motokiwi 8/21/2013 5:11pm
8/21/2013 5:11pm
Is it possible the preload ring slipped on the thread and made the shock go thru part of the stroke faster than it was designed for? Hence blowing it out sideways?
BAMX
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BAMX 8/21/2013 5:32pm
8/21/2013 5:32pm
Why are the threads machined off right next to the crack? That caused looks to have caused a stress riser.
slipdog
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slipdog 8/21/2013 5:41pm
8/21/2013 5:41pm
It's a CRF shock with a 5.4kg spring
ridge
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ridge 8/21/2013 6:11pm
8/21/2013 6:11pm
My guess is the snap ring didn't do it's job and the shock came apart on extension. When he landed, the shaft went in crooked and split the housing. What do you think slip?
ty159
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ty159 8/21/2013 6:13pm
8/21/2013 6:13pm
Some people have that knack... You know the ones that could tear up a fucking anvil...
Brent
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Brent 8/21/2013 6:28pm
8/21/2013 6:28pm
What's the big deal? Just throw some JB Weld on it and its fine....


BOB HANNAH would have won both motos with that shock easy.....





Tongue
ocscottie
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ocscottie 8/21/2013 6:44pm
8/21/2013 6:44pm
slipdog wrote:
It's a CRF shock with a 5.4kg spring
Slippy, do you remember the adjustable struts Chris Wards dad made for KX80's? It has heim joints on each end and you could raise/lower it. Well i fully OJ'd a table at HH by a long way, my rear wheel landed in the dip at the bottom of the table and snapped a heim and my bike STOPPED. Dude i racked my nuts on the gas cap so hard my balls were black a blue for a week. Blink
TX24
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TX24 8/21/2013 7:05pm
8/21/2013 7:05pm
BAMX wrote:
Why are the threads machined off right next to the crack? That caused looks to have caused a stress riser.
The machining does look suspect.
Underground 8/21/2013 7:23pm
8/21/2013 7:23pm
BAMX wrote:
Why are the threads machined off right next to the crack? That caused looks to have caused a stress riser.
Definitely a stress riser point for a part that is pushed beyond it's designed limit.

As any body could imagine, the shim stack for a pro FMX rider is way way harder than standard, so when the designed strength of the shock body derived from calculations and determined by the designing engineer that he thinks it will be exposed to, plus a design safety factor that will allow for unknown loadings and forces is exceeded due to the higher number of shims required to dampen the motion of the shock shaft which is connected to a swing arm on a bike that has just come back to earth from the stratosphere, again, your getting further into that design factor every time you increase the tension of the shim stack. At some point in increasing the shim stack, the force required to open the shim stack x the motion of the shaft is going to over come the strength of the shock body and if there is sharp area or change of section, the crack or failure will usually initiate there. Hence shot peening and linishing of highly stressed parts like conrods and cranks.
Tensile stress=ultimate tensile force/original area. When the force to open the shim stack becomes higher than the tensile strength of the material x thickness x area, something has to give.

It could also just be a case of bad casting with an inclusion or air bubble when poured and unfortunately this one broke due to the high stress as this doesn't happen as much as you would think given the nature of the design use and what these guys do with them. Repeatedly. Would of been way worse it the 80'sWhistling

Paul Thede could better explain this as he's a way better engineer than I'm not. And seeing as it's got his name on it, maybe he should.
ocscottie
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ocscottie 8/21/2013 7:25pm
8/21/2013 7:25pm
GoonSquad250x wrote:
Laughing Laughing Laughing OC your crazy!!!
Get this one...my older bro was racing the '82 LA coliseum amateur SX and he bailed in a weird way, and came falling down onto his bike, as it was laying on its side....dude...he took a footpeg right square in the taint!! Ripped his pants and everything. he sat in the living room recliner for about 5 days, he could barely walk! Looked like he had a badaball bat up his bung LOL

...and the best part, we have it on video!! Laughing

Pit Row

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Underground 8/21/2013 7:31pm
8/21/2013 7:31pm
GoonSquad250x wrote:
Laughing Laughing Laughing OC your crazy!!!
ocscottie wrote:
Get this one...my older bro was racing the '82 LA coliseum amateur SX and he bailed in a weird way, and came falling down onto his...
Get this one...my older bro was racing the '82 LA coliseum amateur SX and he bailed in a weird way, and came falling down onto his bike, as it was laying on its side....dude...he took a footpeg right square in the taint!! Ripped his pants and everything. he sat in the living room recliner for about 5 days, he could barely walk! Looked like he had a badaball bat up his bung LOL

...and the best part, we have it on video!! Laughing
I got tears in my eye's!! And I'm now standing up now cause even the thought of sitting down has the sphinkter in a knot. Did you call him Taint after that?
GoonSquad250x
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GoonSquad250x 8/21/2013 7:33pm
8/21/2013 7:33pm
GoonSquad250x wrote:
Laughing Laughing Laughing OC your crazy!!!
ocscottie wrote:
Get this one...my older bro was racing the '82 LA coliseum amateur SX and he bailed in a weird way, and came falling down onto his...
Get this one...my older bro was racing the '82 LA coliseum amateur SX and he bailed in a weird way, and came falling down onto his bike, as it was laying on its side....dude...he took a footpeg right square in the taint!! Ripped his pants and everything. he sat in the living room recliner for about 5 days, he could barely walk! Looked like he had a badaball bat up his bung LOL

...and the best part, we have it on video!! Laughing
Ahahaha!!!!! No mercy on your poor bro. I hope everything is still "running". You've got to dig this vid up. That'll be a good thread Grinning
BAMX
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BAMX 8/21/2013 8:13pm
8/21/2013 8:13pm
Underground wrote:
Definitely a stress riser point for a part that is pushed beyond it's designed limit. As any body could imagine, the shim stack for a pro...
Definitely a stress riser point for a part that is pushed beyond it's designed limit.

As any body could imagine, the shim stack for a pro FMX rider is way way harder than standard, so when the designed strength of the shock body derived from calculations and determined by the designing engineer that he thinks it will be exposed to, plus a design safety factor that will allow for unknown loadings and forces is exceeded due to the higher number of shims required to dampen the motion of the shock shaft which is connected to a swing arm on a bike that has just come back to earth from the stratosphere, again, your getting further into that design factor every time you increase the tension of the shim stack. At some point in increasing the shim stack, the force required to open the shim stack x the motion of the shaft is going to over come the strength of the shock body and if there is sharp area or change of section, the crack or failure will usually initiate there. Hence shot peening and linishing of highly stressed parts like conrods and cranks.
Tensile stress=ultimate tensile force/original area. When the force to open the shim stack becomes higher than the tensile strength of the material x thickness x area, something has to give.

It could also just be a case of bad casting with an inclusion or air bubble when poured and unfortunately this one broke due to the high stress as this doesn't happen as much as you would think given the nature of the design use and what these guys do with them. Repeatedly. Would of been way worse it the 80'sWhistling

Paul Thede could better explain this as he's a way better engineer than I'm not. And seeing as it's got his name on it, maybe he should.
I was wondering why the threads are machined away. I don't have a new model Honda but I have never seen anything like that. It would be interesting to hear Thede's take on this. I know that one of his managers trolls Vital. Maybe he could make that happen
TeamPropainTurbo38t 8/21/2013 8:22pm
8/21/2013 8:22pm
That machining didn't cause the break....it broke from the botom.....see how it's split open wider at the bottom? No machining but it definitely started at the bottom. My thoughts.....either a bad casting(casting mark in the bottom of the shock body ) caused a crack, the Race Tech Spring seat had a cast mark on it and wore the shock body(highly unlikely) or some other component failed(my guess)......could have been his pivot bearings locked up causing the rod to bend which could have caused ths.....but I'd say definitely no on those machining marks. Dave
slipdog
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slipdog 8/21/2013 8:29pm
8/21/2013 8:29pm
ridge wrote:
My guess is the snap ring didn't do it's job and the shock came apart on extension. When he landed, the shaft went in crooked and...
My guess is the snap ring didn't do it's job and the shock came apart on extension. When he landed, the shaft went in crooked and split the housing. What do you think slip?
Honestly there could be many different reasons the led to the failure, but it really can't be determined form just a picture.
ocscottie
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ocscottie 8/21/2013 8:33pm
8/21/2013 8:33pm
GoonSquad250x wrote:
Ahahaha!!!!! No mercy on your poor bro. I hope everything is still "running". You've got to dig this vid up. That'll be a good thread Grinning
He fathered two wonderfully awesome kids so, all is well in that department lol ...but about 1/2 an inch either way and he would of been in big trouble!! Blink
slipdog
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slipdog 8/21/2013 8:34pm
8/21/2013 8:34pm
slipdog wrote:
It's a CRF shock with a 5.4kg spring
ocscottie wrote:
Slippy, do you remember the adjustable struts Chris Wards dad made for KX80's? It has heim joints on each end and you could raise/lower it. Well...
Slippy, do you remember the adjustable struts Chris Wards dad made for KX80's? It has heim joints on each end and you could raise/lower it. Well i fully OJ'd a table at HH by a long way, my rear wheel landed in the dip at the bottom of the table and snapped a heim and my bike STOPPED. Dude i racked my nuts on the gas cap so hard my balls were black a blue for a week. Blink
I do remember those and wanted one for my KX60 because they looked soooooo factory. I had the linkage pull rod rip of the frame of my KX125 at the last round of the Trans Cal and came to a complete stop also. I got pitched over the bars and got lucky and landed on my ass and not my head. DNF and lost the title by 1point...
ocscottie
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ocscottie 8/21/2013 8:38pm
8/21/2013 8:38pm Edited Date/Time 8/21/2013 8:39pm
"DNF and lost the title by 1point... "

OWCH!!!! talk about adding insult to injury...damn bro! Pinch

He also made me these cool alumi bar riders. I had a growth spurt and was getting too tall.
GoonSquad250x
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GoonSquad250x 8/21/2013 8:44pm
8/21/2013 8:44pm
GoonSquad250x wrote:
Ahahaha!!!!! No mercy on your poor bro. I hope everything is still "running". You've got to dig this vid up. That'll be a good thread Grinning
ocscottie wrote:
He fathered two wonderfully awesome kids so, all is well in that department lol ...but about 1/2 an inch either way and he would of been...
He fathered two wonderfully awesome kids so, all is well in that department lol ...but about 1/2 an inch either way and he would of been in big trouble!! Blink
Aww man!!! Good thing. I've always been worried about something stabbing me in the woods. limbs stuff always reaching out to grab and poke you. Ever played joust with a tree limb and your limb? Not coolDizzy
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SLAPAHO 8/21/2013 9:58pm
8/21/2013 9:58pm
DocMarten wrote:
is this off a bike or some kind of truck/UTV ??
just out of curiosity, wtf do you think its off of?
bvm111
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bvm111 8/21/2013 9:59pm
8/21/2013 9:59pm
GoonSquad250x wrote:
Laughing Laughing Laughing OC your crazy!!!
ocscottie wrote:
Get this one...my older bro was racing the '82 LA coliseum amateur SX and he bailed in a weird way, and came falling down onto his...
Get this one...my older bro was racing the '82 LA coliseum amateur SX and he bailed in a weird way, and came falling down onto his bike, as it was laying on its side....dude...he took a footpeg right square in the taint!! Ripped his pants and everything. he sat in the living room recliner for about 5 days, he could barely walk! Looked like he had a badaball bat up his bung LOL

...and the best part, we have it on video!! Laughing
Dude Scottie you HAVE to post up the video!!!

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