KTM broke in half.

Thisusernameisavailable 4/16/2022 10:58pm
4/16/2022 10:58pm
bvm111 wrote:
it was only 15Nm … back at 20Nm, going to throw that on the pre ride check list! Thanks for the info Billy….Get the torque wrenches...
it was only 15Nm … back at 20Nm, going to throw that on the pre ride check list!

Thanks for the info Billy….Get the torque wrenches out fellas!
Just to screw with your head- when was the last time your torque wrench was calibrated?
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PFitzG38
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PFitzG38 4/16/2022 11:24pm
4/16/2022 11:24pm
soresammy wrote:
So four "freak accidents" happen in the last two weeks that involve your parts in the failures. I don't think anyone is ganging up on you...
So four "freak accidents" happen in the last two weeks that involve your parts in the failures. I don't think anyone is ganging up on you ( actually most on here are sticking up for you ), but if you don't feel there is an issue then there is a bigger problem. This isn't a small issue. This could be life ending or life changing. Instead of getting defensive and being a wise ass, it would probably be a good thing if you put your energy into figuring what is going on. If someone gets seriously injured ( or worse ) your responses on here are going to Bury you in court. Can you imagine Mitch Payton responding the way you have been ( the owner of Luxon, I'm assuming)??? I actually had to scroll back in the other thread to makesure It was really the responses of Luxon. Super unprofessional, and actually shocking.
Your reading comprehension is sorely lacking. Pay attention before make stupid comments. Maybe read what your commenting on twice- just a suggestion
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KurtJ99
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KurtJ99 4/16/2022 11:26pm
4/16/2022 11:26pm
Throughout my career, I’ve seen designs with low safety margins both by mistake and design intent. Personally I would rather have a higher weight and safety margin and not have to worry about a narrow window for screw preload for normal use. Screw preload is a tricky thing too. It depends on thread friction and can vary a lot depending on the thread condition. I remember doing strain gauge tests under various thread conditions and thread locks /lubricants and it would vary 30% in some cases. The clamp threads and screws may be very repeatable and low friction so maybe that is under control.
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JM485
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JM485 4/17/2022 12:06am
4/17/2022 12:06am
Brent wrote:
[img]https://p.vitalmx.com/photos/forums/2022/04/16/544274/s1200_IMG_3269.jpg[/img] [img]https://p.vitalmx.com/photos/forums/2022/04/16/544275/s1200_IMG_3270.jpg[/img] Go with What you know. The Germans don't fuck around. Just sayin'



Go with What you know.
The Germans don't fuck around.
Just sayin'
I’m curious to hear what is so different about that design that you think it would have prevented this type of failure. I’ll wait. . .
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GuyB
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GuyB 4/17/2022 12:11am
4/17/2022 12:11am
This is an example of one of the things that used to be super-frustrating to me.

People want insider info. But then an insider comes here, speaks openly, and spends what was probably a fair amount of time crafting a perfectly reasonable explanation. Then he gets told he's wrong. Eventually, the insider(s) stop responding, and the vacuum is filled with nonsense from people who are speculating, rather than speaking from actual experience.
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VRR7
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VRR7 4/17/2022 12:13am
4/17/2022 12:13am
Just eye balling this picture you can see this is a weak spot in design.


This YZ clamp look much stronger by design.

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soresammy
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soresammy 4/17/2022 12:21am
4/17/2022 12:21am Edited Date/Time 4/17/2022 12:23am
soresammy wrote:
So four "freak accidents" happen in the last two weeks that involve your parts in the failures. I don't think anyone is ganging up on you...
So four "freak accidents" happen in the last two weeks that involve your parts in the failures. I don't think anyone is ganging up on you ( actually most on here are sticking up for you ), but if you don't feel there is an issue then there is a bigger problem. This isn't a small issue. This could be life ending or life changing. Instead of getting defensive and being a wise ass, it would probably be a good thing if you put your energy into figuring what is going on. If someone gets seriously injured ( or worse ) your responses on here are going to Bury you in court. Can you imagine Mitch Payton responding the way you have been ( the owner of Luxon, I'm assuming)??? I actually had to scroll back in the other thread to makesure It was really the responses of Luxon. Super unprofessional, and actually shocking.
PFitzG38 wrote:
Your reading comprehension is sorely lacking. Pay attention before make stupid comments. Maybe read what your commenting on twice- just a suggestion
Actually it's spot on. So spot on that the other thread that I said "would bury him" do to his comments has mysteriously disappeared. Don't try to be a dick in a forum. Not a good look.
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KurtJ99
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KurtJ99 4/17/2022 12:29am
4/17/2022 12:29am
GuyB wrote:
This is an example of one of the things that used to be super-frustrating to me. People want insider info. But then an insider comes here...
This is an example of one of the things that used to be super-frustrating to me.

People want insider info. But then an insider comes here, speaks openly, and spends what was probably a fair amount of time crafting a perfectly reasonable explanation. Then he gets told he's wrong. Eventually, the insider(s) stop responding, and the vacuum is filled with nonsense from people who are speculating, rather than speaking from actual experience.
You aren’t going to stop uninformed dumbass criticism. I still think it’s a favorable tradeoff to provide expert product knowledge to enthusiasts likely to buy product.
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GuyB
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GuyB 4/17/2022 12:33am
4/17/2022 12:33am
KurtJ99 wrote:
You aren’t going to stop uninformed dumbass criticism. I still think it’s a favorable tradeoff to provide expert product knowledge to enthusiasts likely to buy product.
Trust me, I know it's not going to stop. There are millions of examples daily on social media.

It's just unfortunate that people who shouldn't necessarily have a megaphone available don't know when to refrain from using one.
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jeffro503
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jeffro503 4/17/2022 12:42am
4/17/2022 12:42am
KurtJ99 wrote:
You aren’t going to stop uninformed dumbass criticism. I still think it’s a favorable tradeoff to provide expert product knowledge to enthusiasts likely to buy product.
GuyB wrote:
Trust me, I know it's not going to stop. There are millions of examples daily on social media. It's just unfortunate that people who shouldn't necessarily...
Trust me, I know it's not going to stop. There are millions of examples daily on social media.

It's just unfortunate that people who shouldn't necessarily have a megaphone available don't know when to refrain from using one.
Steve , you know as well as I do , dumbass people come out of the woodwork on topics like this. BTW.....it's good to see you here dude. Like to see more of it.
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GuyB
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GuyB 4/17/2022 12:45am
4/17/2022 12:45am Edited Date/Time 4/17/2022 12:46am
jeffro503 wrote:
Steve , you know as well as I do , dumbass people come out of the woodwork on topics like this. BTW.....it's good to see you...
Steve , you know as well as I do , dumbass people come out of the woodwork on topics like this. BTW.....it's good to see you here dude. Like to see more of it.
20 years of admin time was enough for me. I peek in (very) occasionally but have plenty of other things to do to stay occupied. Smile
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Sandusky26
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Sandusky26 4/17/2022 1:48am
4/17/2022 1:48am
I started this thread to talk about the KTM, didn’t mean to drag Luxon into it. I run OEM Suzuki clamps, the best.
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alex69
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alex69 4/17/2022 2:11am
4/17/2022 2:11am
Luxon MX wrote:
I'm glad the internet engineers have already found the problem and concluded that our product is junk. Can't wait for the internet lawyers to jump in...
I'm glad the internet engineers have already found the problem and concluded that our product is junk. Can't wait for the internet lawyers to jump in too!

I'm not at Atlanta, but from what I can tell at this point is that the pinch bolt at the stem failed, which caused the top clamp to fail, and then the bike to "break in half".

The KTM design uses the top triple clamp to clamp around the steering stem with a pinch bolt instead of the "standard" Japanese bike design where the top clamp is sandwiched between the adjuster nut and the lock nut. It's a pretty elegant design, but if the bolt fails, then the assembly becomes very weak and the clamp will fail. This is the same design that KTM/Husky/GasGas use on all of their stock clamps and factory clamp and multiple aftermarket companies use on their clamps for these bikes.

Here's the actual broken part from today:



You can see the broken bolt on the right, which allowed the clamp to break (on the left). Note the fresh break of the clamp and that there's no fretting or other evidence of a previous crack. That shows this happened all at once and the clamp itself wasn't the problem, it was the bolt. We use bolts that are stronger than the stock KTM bolts (random samples tested to failure for each batch we receive), so either the bolt was over-torqued to the point that it was on the edge of failure, or it came loose and that allowed things to give way.

This is the first failure of this kind for us, but it's not all that uncommon with this general design. Multiple other aftermarket clamps and stock KTM clamps have all failed in the same way. Not because the clamps are bad, but because the bolt failed; most likely because it was over torqued or came loose.

Regardless, we'll take a closer look at the clamps when we get them back to see if there's anything that I'm missing from the photos, but it seems pretty clear cut. If this were a design problem, we'd see this a whole lot more instead of this one incident. Freddie Noren has been on this same setup all year successfully and finished 11th in the 450 class today.

Here's a few examples of the same failure, stock and aftermarket, I'm sure there's plenty more I don't have photos of:








Ktm also uses a stronger bolt than stock in the triple clamp, you can tell because these are slightly darker grey.
This is also the case with the disc brake bolts.
The bolts are easy to mix up.
And this bolt is constantly under tension, the tightening torque was good.
But of course you can destroy everything with brute force.
But before 1992 this was more rule than coincidence, the materials have improved enormously.
1
cwel11
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cwel11 4/17/2022 3:18am
4/17/2022 3:18am
I’ve personally never bought a Luxon MX product ever. But I absolutely will now. I own my own construction business and deal with shit products from shit companies on a daily basis. I constantly get ghosted by companies with no answer to defects in what use to be quality materials. Do any of you guys bashing this company have any idea how refreshing it is for a company to be this open and responsive on a forum? If they find there is a defect issue, after reading their response I have no doubt they would fix it properly.
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rbm33
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rbm33 4/17/2022 5:36am
4/17/2022 5:36am
Luxon MX wrote:
I'm glad the internet engineers have already found the problem and concluded that our product is junk. Can't wait for the internet lawyers to jump in...
I'm glad the internet engineers have already found the problem and concluded that our product is junk. Can't wait for the internet lawyers to jump in too!

I'm not at Atlanta, but from what I can tell at this point is that the pinch bolt at the stem failed, which caused the top clamp to fail, and then the bike to "break in half".

The KTM design uses the top triple clamp to clamp around the steering stem with a pinch bolt instead of the "standard" Japanese bike design where the top clamp is sandwiched between the adjuster nut and the lock nut. It's a pretty elegant design, but if the bolt fails, then the assembly becomes very weak and the clamp will fail. This is the same design that KTM/Husky/GasGas use on all of their stock clamps and factory clamp and multiple aftermarket companies use on their clamps for these bikes.

Here's the actual broken part from today:



You can see the broken bolt on the right, which allowed the clamp to break (on the left). Note the fresh break of the clamp and that there's no fretting or other evidence of a previous crack. That shows this happened all at once and the clamp itself wasn't the problem, it was the bolt. We use bolts that are stronger than the stock KTM bolts (random samples tested to failure for each batch we receive), so either the bolt was over-torqued to the point that it was on the edge of failure, or it came loose and that allowed things to give way.

This is the first failure of this kind for us, but it's not all that uncommon with this general design. Multiple other aftermarket clamps and stock KTM clamps have all failed in the same way. Not because the clamps are bad, but because the bolt failed; most likely because it was over torqued or came loose.

Regardless, we'll take a closer look at the clamps when we get them back to see if there's anything that I'm missing from the photos, but it seems pretty clear cut. If this were a design problem, we'd see this a whole lot more instead of this one incident. Freddie Noren has been on this same setup all year successfully and finished 11th in the 450 class today.

Here's a few examples of the same failure, stock and aftermarket, I'm sure there's plenty more I don't have photos of:








I'm not criticizing, I'm actually a big fan of your products. I have been involved in mechanical design for over 30 years and I cant help but wonder why you don't design a full clamp for the Austrian bikes that's similar to the Japanese style of triple clamps?
The KTM design is obviously very dependent on the quality and installation of the pinch bolt and has had many failures in the past whereas the Japanese design is very tried and true.
It seems you have the knowledge and capabilities to design and manufacture and clap far superior to the KTM clamp as opposed to just offering a little better version of the same basic design.
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nrtec
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nrtec 4/17/2022 5:41am
4/17/2022 5:41am
I was working as a machinist in a shock absorber compagny and we had many issue with aluminium quality, as I guess mainly come from asia, I've seen part break that should not break
High stress with poor material is not ideal, but in the case of the triple clamp I can see many solutions to make it stronger as we know that pinch bolt design is not the best
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kb228
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kb228 4/17/2022 5:57am
4/17/2022 5:57am
As a product engineer myself i cant help but think, why is KTM trusting an 8mm bolt to hold half the bike together while every other japanese company is using a huge 1” or so diameter shaft thats double nutted?

Beefing up that area and adding a method of keeping that bolt tight such as blue locktite or a flanged bolt with a serrated flange would be a good idea. Maybe bumping up the size of the bolt so tensile strength is higher.

Just my thoughts. I dont design motorcycle parts but these things are worth looking at
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MX558
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MX558 4/17/2022 6:00am
4/17/2022 6:00am
I just went and checked my bolt on my 350 , looks like it was good a 30 nm . That is a shit design though , not to mention it's a 6mm bolt
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resetjet
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resetjet 4/17/2022 6:08am
4/17/2022 6:08am
I guess “we need a bigger boat”. Or bolt. Or
Two bolts.
2
RandomUserName 4/17/2022 6:16am
4/17/2022 6:16am
GuyB wrote:
This is an example of one of the things that used to be super-frustrating to me. People want insider info. But then an insider comes here...
This is an example of one of the things that used to be super-frustrating to me.

People want insider info. But then an insider comes here, speaks openly, and spends what was probably a fair amount of time crafting a perfectly reasonable explanation. Then he gets told he's wrong. Eventually, the insider(s) stop responding, and the vacuum is filled with nonsense from people who are speculating, rather than speaking from actual experience.
actually...I just re-read this and while there were a couple of dumbass comments, we also have 30+year machinists in here simply spitballing ideas and theories on things, and doing so quite respectfully. I knew the Luxon guy would get dragged into this as soon as I saw this thread and he has done a fine job of explaining things though was a bit defensive cause his name was brought up. I suppose I would be defensive a little as well.

your disdain for your users (even post retirement) is mind-boggling.
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Johnny Ringo
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Johnny Ringo 4/17/2022 6:29am
4/17/2022 6:29am
“Lightest bike in the class”
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MyBobbym
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MyBobbym 4/17/2022 6:35am
4/17/2022 6:35am
Luxon MX wrote:
I'm glad the internet engineers have already found the problem and concluded that our product is junk. Can't wait for the internet lawyers to jump in...
I'm glad the internet engineers have already found the problem and concluded that our product is junk. Can't wait for the internet lawyers to jump in too!

I'm not at Atlanta, but from what I can tell at this point is that the pinch bolt at the stem failed, which caused the top clamp to fail, and then the bike to "break in half".

The KTM design uses the top triple clamp to clamp around the steering stem with a pinch bolt instead of the "standard" Japanese bike design where the top clamp is sandwiched between the adjuster nut and the lock nut. It's a pretty elegant design, but if the bolt fails, then the assembly becomes very weak and the clamp will fail. This is the same design that KTM/Husky/GasGas use on all of their stock clamps and factory clamp and multiple aftermarket companies use on their clamps for these bikes.

Here's the actual broken part from today:



You can see the broken bolt on the right, which allowed the clamp to break (on the left). Note the fresh break of the clamp and that there's no fretting or other evidence of a previous crack. That shows this happened all at once and the clamp itself wasn't the problem, it was the bolt. We use bolts that are stronger than the stock KTM bolts (random samples tested to failure for each batch we receive), so either the bolt was over-torqued to the point that it was on the edge of failure, or it came loose and that allowed things to give way.

This is the first failure of this kind for us, but it's not all that uncommon with this general design. Multiple other aftermarket clamps and stock KTM clamps have all failed in the same way. Not because the clamps are bad, but because the bolt failed; most likely because it was over torqued or came loose.

Regardless, we'll take a closer look at the clamps when we get them back to see if there's anything that I'm missing from the photos, but it seems pretty clear cut. If this were a design problem, we'd see this a whole lot more instead of this one incident. Freddie Noren has been on this same setup all year successfully and finished 11th in the 450 class today.

Here's a few examples of the same failure, stock and aftermarket, I'm sure there's plenty more I don't have photos of:








Cluttering up this post with actual facts? Tsk...tsk..
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sandman768
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sandman768 4/17/2022 6:36am
4/17/2022 6:36am
I have learned over time owning several KtM”s, that this bolt needs to be checked often. I had this bolt break on my 17 FE 450, the head of the bolt was completely missing! I have seen the bolt loosen up also. Another thing to consider is the sequence in which the top clamp bolts get tightened. The top 17mm headed bolts gets tightened first, before this 10mm headed bolt, then the upper clamp bolts. I could see if the sequence was not done correctly, it could put unnecessary torque on the suspect bolt. This is an area that KtM should revise for more strength for sure…
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bvm111
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bvm111 4/17/2022 6:36am
4/17/2022 6:36am
bvm111 wrote:
it was only 15Nm … back at 20Nm, going to throw that on the pre ride check list! Thanks for the info Billy….Get the torque wrenches...
it was only 15Nm … back at 20Nm, going to throw that on the pre ride check list!

Thanks for the info Billy….Get the torque wrenches out fellas!
Thisusernameisavailable wrote:
Just to screw with your head- when was the last time your torque wrench was calibrated?
oh man that really screwed with my head… man you got me, good one! Blink
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Brent
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Brent 4/17/2022 6:37am
4/17/2022 6:37am
JM485 wrote:
I’m curious to hear what is so different about that design that you think it would have prevented this type of failure. I’ll wait. . .
There are a couple of specific reasons, but sharing the details here is pointless and would only invite more poo throwing from the monkeys.

That said, I believe Luxon is a good, well constructed clamp- and maybe no upper clamp of this basic weight saving design could survive an apparent front compression impact that this bike in ATL possibly suffered regardless of who made it.

Maybe something different happened, who knows.

Same broken upper clamp on a 2022 KTM two stroke happened at a local race at Glen Helen about three weeks ago, I believe it was a stock clamp that broke the same way in the same place.

If you apply enough force, anything will break.
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FahQ
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FahQ 4/17/2022 6:54am
4/17/2022 6:54am
Seems like there could be a market for a Japanese style “Heavy Duty” top clamp.
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Timo
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Timo 4/17/2022 6:54am
4/17/2022 6:54am
GuyB wrote:
20 years of admin time was enough for me. I peek in (very) occasionally but have plenty of other things to do to stay occupied. Smile
Aka has a burner account to stay anonymous...
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Sandusky26
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Sandusky26 4/17/2022 7:10am
4/17/2022 7:10am
Luxon vs Ride Engineering, who would win in a fight?
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chuckie108
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chuckie108 4/17/2022 7:42am
4/17/2022 7:42am
Being a generic internet engineer myself- I’d like to know if some of the actual engineers on here have an opinion on this. It appears to me that the only way to cause this type of failure would be to load the front wheel with a large force back towards the down tube through the front wheel. Like hitting a wall, or flipping the bike down the track. It’s seams to me, the big forces you’d see during normal riding, casing a triple for example, would load the tripe clamp in the other direction. Point being, all the fear of the Austrian’s “inferior design” may not actually be realistic. Unless you plan on running into a wall anytime soon, or front braking forces rise substantially.
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