Wonder who made the clamps

Unfortunately the internet is a place where a photo/video can be posted without any context and the speculation can run wild…

I just got off the phone with Riley a few minutes ago, talked about what happened, and have received a few photos of the parts. Here are four important facts about the situation:

     1) Riley specifically said that the clamps broke because of the crash and were not the cause of the crash. This is the most important part, and if it were the other way around, this would be a very different story!

          * When a professional level rider on a supercross track has a big crash, something is going to break. In this case it was our clamps. In countless other cases this year and in years past, it has been other parts. It’s just a fact of riding, things break in a crash.

     2) The clamps broke at the titanium bolt on the steering stem (more on this below).

     3) The clamps that broke were over a year old and they were the first version of these clamps that we made. Since then, we’ve made a few revisions to beef up this spot:

          * We changed that titanium bolt to a higher strength steel bolt (that’s also a bit more resilient to torque variation)

          * We changed the geometry of the top clamp slightly to make it a little stronger in that spot

          * This isn’t to say that the previous design was no good, we have hundreds of these out there with only two failures (including this one). But these changes make it a little more robust, so we improved things a bit as we do with all of our products over time.

     4) Riley is replacing the clamps that broke with another set of Luxon clamps he has.

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Now, regardless of those facts, I realize that this looks bad since this has happened once before with our clamps. Here’s what happened with that situation:

     1) Despite the team stating that they would send the clamps back to us, and despite them saying they’d send an email later with their thoughts and with more information, neither of those things happened. I reminded them multiple times, and nothing ever happened.

     2) There’s no photos or video of that crash available to review

     3) I have seen a video on Instagram of that team torquing the top and bottom triple clamp bolts to the same level. This is incorrect and I even messaged them as such. This doesn’t build confidence that they torqued everything else correctly.

Given all that, there’s nothing to do but come to a conclusion based on the evidence I have. Clearly, the stem bolt broke in that situation, but why? There’s evidence of them torquing the other bolts incorrectly. Plus we have a lot of these clamps out there; with very fast professional riders and with many amateur riders. Three years of these clamps, without a problem. So my best conclusion based on the evidence we have is one of two scenarios:

     a) They over-torqued the bolt, which caused it to break in a high stress scenario, which caused a crash.

     or

     b) There was a big crash and things broke

In response to that, we made the design changes I mentioned above. Regardless, either version of our clamp has been shown to have no issues when properly installed and maintained.

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Finally, I’ll address the general design of the KTM style clamps - this applies to all KTM/Husky/GasGas clamps and most all aftermarket clamps for those bikes. The fact that the top clamp is slit in order to clamp around the stem isn’t ideal, but it is necessary in their particular design. It all comes down to the clamp bolt. If that bolt breaks, comes loose, or otherwise isn’t tensioned correctly, it will break and the whole front end of the bike comes off with it. It makes for great photos and videos on Instagram, but it’s not a great design in general. I’ve shown multiple photos of this broken on both stock and other aftermarket KTM triple clamps.

Why not just change it? Well, it’s not that simple, unfortunately. There’s only so much room to work with there. If you were to convert the design over to a “traditional” style like the Japanese bikes use, you have to make room for the additional nuts and washers. The top triple clamp on the previous generation KTM was only about 26 mm thick. On the latest generation, it’s even thinner at about 23 mm. The adjustment nut takes up about 10mm of thickness, which leaves you with only 13 mm (1/2 inch) of triple clamp at that point. That’s not very strong either… With these changes, you also lose all compatibility with aftermarket bar mounts, steering stabilizers, etc., so it really reduces the value of the clamps to a lot of riders.

We are looking into alternatives to get around this, but like I said, it’s not straight forward. The current design, though a week point, does work fine so long as it’s properly installed and maintained.

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I think that pretty well covers the situation. If anyone has a relevant question that I missed, either ask it here, shoot me an email, or give us a call.   billy@luxonmx.com   858-586-1100 x101

822 Riley Ripper out of Houston ,,  and yes my understanding is that he is fine.

One more point since there’s a lot of question about it in this thread: the Xtrig clamps use a pinch bolt on all their clamps with adjustable offset and no pinch bolt on their clamps with a fixed offset for the Japanese bikes. The reason for that is the offset adjustment is done with an eccentric feature on the stem (flipping the stem changes the offset). There’s just not enough room to make the traditional style threaded stem work with this eccentric feature, so they use the pinch bolt style on those clamps.

Our upcoming Gen3 Pro clamps also have adjustable offset, but that is done with an eccentric insert in the top clamp rather than the stem itself. We’re able to keep the traditional threaded stem on the Japanese bikes that way. We are looking into how we can incorporate this with the KTM bikes as well, but as mentioned before, it’s not as easy with the limitations we have to work around.

For KX450....The X Trig Roc Pros (Red Ones that you can run 21 mm or 23 mm) come with a pinch bolt, just like the honda pictured. The green ones which can only be run at 23 mm, come without a pinch bolt, just like the kx pictured. I have 1 set of each. Performance is the same when ran at 23 mm. Green ones cost a little less. 

I also ran luxon 21.5 mm offset for a while. They did not break on me, felt comfortable on them. I just preferred the 23 mm offset when riding moto tracks such as GH. Personal preference as i know a lot of people do like the 21.5 mm offset for moto. 

No matter how this thing goes, and they often go sideways here, I have a lot of respect for Billy coming in and explaining things.  I’ve owned Ktm’s with this style clamp for hundreds and hundreds of hours of seat time without any issues so I do not think it is a bad design.  On the contrary, it’s easier to service and way easier to adjust bearing preload giving you a little bit of a dampener effect.  And if I was going to buy aftermarket clamps I’d have no reservations about going with Luxon. 

Checking the front end is one of the first things I taught my 16 year old when he started being responsible for his bike (3 years ago). He knows that clean surfaces, the proper grease for the proper bolt, loc-tite, a bench grinder wire wheel, and a good toruque wrench properly used are all critical. Along with spoke checks, I feel this is a critical safety step a LOT of riders overlook. When was the last time you pulled your bar mounts off and checked the bars and mounts, then retorqued properly? Hell, I see guys at the track all the time that haven't washed their bike since the last weekend, much less done a bolt check. This shit is under a LOT of stress, especially if you are fast. We also do full frame bolt checks every 4-6 weeks, and use torque-seal on the critical stuff. Ya gotta pay attention and do it right, every time. My kid might never be a Pro-level rider, but one day he might wrench for one, and he'll be good at it. He's got about 1/2 the torque settings for a KTM memorized already.

I think the Luxon clamps are absolutely amazing, and revolutionary in design, technology, and function.  They are stunningly beautiful as well.  The fact that Billy is one of the only owners of a relatively large moto company, who comes on this forum to discuss, and explain his products, speaks highly of his integrity and his belief in his products.  I have no problem or worry whatsoever in running Luxon clamps on my 2021 KX250. 
Thanks for coming on here and giving us the scoop Billy, I appreciate it. 👍

I respect but don't envy the guy from Luxon for talking to us.  I have the Luxon handlebar holders for my Kawi and KTM and i think they are the best available.   Phenomenal quality.  I don't know the company or have any affiliation with anyone....i like the good stuff on my bike.    

I always run the stock triple clamps because why?   So can't attest to the quality of that.

Any time a design relies on competent input from the consumer to avoid catastrophic failure, there is going to be catastrophic failure. Not necessarily because of the design, but because of the distracted home mechanic that applies too much or too little torque if he remembered to tighten that bolt at all. The traditional design seems more fool proof, with less consequence in the event of user error. Billy seems a bit frustrated having to work around this design.

Wouldn't most customers of those product also not have factory teams taking care of their bikes?

How many people have ever crack tested a single part of their bike ? 

Or even looked for cracks. 

No, thought not. 

Stuff breaks. 

Stuff that isnt  checked , breaks more. 

FWIW, the Husky head idea is fucking shit IMO, our SM setup uses Cobra clamps and a proper retaining ring so when you take the top clamp off, the whole thing doesnt fall out. 

Maybe don't use titanium for steering stem bolts...

About maintenance... Some years back I bought a used Japanese 250F, and tore it down to inspect/rebuild/service everything that needed it. I look for cracks in things like triple clamps...this machine had the stockers on it. They had no visible defects. I was torquing the upper clamp pinch bolts to factory spec (with a beam type torque wrench), and l they just snapped. I mean the bolt bosses on both sides plus about a half inch of the thinner bit was just gone. At some point in it's service history, that clamp was overstressed. Either in a crash, or by substantially over torquing. So who knows what might have happened in this case...

That is covered in Billy’s response.

I agree it was a lot easier!  I just hand tightened it till the drag on the handlebars felt right beacause unless I took the handlebars off I could only get a wrench on it. OH I did have the manual open to find the torque and they tell you to put loctite on everything.

Absolutely love that Billy isn’t afraid to come on here and explain what’s up. These companies are the ones we should be supporting not bashing. Last time he did this I bought their bar mount setup. Maybe this time I’ll spring for some more Luxon goodies. 

Billy is one of like 4-5 people's opinions on this site worth paying attention to.

Most room temp IQ riders would rather drop 1k on the same dog shit pipes FMF has been churning out for 20 years instead of Luxon products w/ actual R&D behind it lol

I didn’t see any mention of not using titanium for that bolt. He just said titanium is used. 
 

maybe I missed it. 

There’s no maybe about it. 

Oh I see it now. Few lines down. New versions are using steel bolts. 
 
That’s good. Should of been from the start  

I don't understand what the fuss is about, with a big impact, something got to give.

Wouldn't it be better that clamps break, rather than bend the frame, or break expensive forks?

A sacrificial shear point, the clamps!

I use a few Ti fasteners. The best ones come from aerospace and unfortunately are imperial thread sizes and generally for double shear designs.

The familiar metric Ti fasteners used on our bikes, have the reduced hex size and the flange, are Grade 5 Titanium- 6al4v- which is a strong grade but in bolt form not really high tensile- somewhere between 8.8 and 10.9 on the steel bolt scale. Some of the aerospace bolts are far harder and stronger than the commercial bike bolts despite being made of the same grade material, the best ones are made of exotic alloys 'to order'.

Problem is these aftermarket titanium bolts are not made to a recognised ISO/SAE/JIS standard and the source and provenance of the bar they are machined/thread rolled from is unknown. There is a lot of cheap Russian and Chinese Ti bar out there and I am sure it is being used.

Bottom line is most professional mechanics are well aware of this and know what OE stuff to leave alone.

Theirs a big fuss because a bike just broke in half. It's kind of a big deal.

It didn't just break in half, it had a catstrophic crash.

Something got to give.

It is terrifying looking at certain sellers, some who have factory teams rely on them for their 'expertise', with Ti axles that are £150 or so. The last set of axles we made were for our YZ465 and the material cost that per axle with a proper mill cert, not a hooky Chinese one with different dates and batch numbers obviously copied and pasted on to it. Then having them heat treated cost not far off the same again per axle. So, with labour, I know I'd be at more than double their prices slapping a markup on it. There is a reason proper Ti gear costs money.

And that's what matters, having a chain of accountability. If it were for a customer, and something fails, I have two pieces of paperwork I can wave at a courtroom showing that I did my homework. If I used some random ebay Ti bolt and send that out the door I'd deserve what I got when it went wrong.

I’m scared for you. 

"Bolted joint analysis" is a neat science to learn about. With a conventional joint, where two parts are clamped directly together, it can (and should) be designed so that the abutment itself takes the majority of the stress.

A "pinch clamp" like the ktm design is kind of a worst case scenario, and the bolt will take the majority of the stress. Fastener material choice is critical. Good to see luxon has now gone to a steel bolt at that location.

Anyone know what the crash looked like? Or better yet have video?

Man, that is not a lot of material in the bolt head area of the pinch clamp (aluminum cross section).  I know it's been said that the crash is what caused the failure, but that Austrian design is scary looking.

I agree.