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3388
Joined
7/28/2021
Location
Eastern, NC
US
Edited Date/Time
6/4/2022 12:43pm
What happened to that hippie mobile?
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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:
Go with What you know.
The Germans don't fuck around.
Just sayin'
Pit Row
So not uncommon, and yesterday's big jump video shows what abuse these bikes get on the track and then constant swapping suspension and all that, parts are gonna wear and fatigue quickly.
1) Failure due to crash - This is going to happen no matter who makes the parts. If you crash hard enough, something is going to break. Simple as that. Sure, we can engineer parts like a tank. They'd never break, but you'd be riding around on a tank! That's no good. In the quest for the lightest parts available that still preform well, you're going to get some failures from crashes. Often times if the part breaks because of a crash, the rider is pretty broken too. At worst, it causes a DNF. But it's not a safety issue at all.
2) Failure due to improper installation - This is something that's a little out of our control. There is only so much a manufacturer can do about this. Mitigation with good instructions, etc., which we do. We also have torque specs engraved directly on the clamps to help. But if a bolt is over-torqued, it will be over-stressed. If it's under-torqued, it will allow the assembly to split apart.
3) Failure due to a poor design - This is obviously a concern and a huge safety issue. So far, I am 100% confident that no failure of our parts can be attributed to this. I myself ride with these parts, as do 100s of others without issue.
We have hard video evidence that the initial failures you mention (from Daytona) were due to crashes, not the cause of crashes. There are other factors at play that make it even less of an issue for our customers (feel free to read the other thread for all that). So, I'm not blowing those off, but I'm not terribly concerned either.
This latest failure on the KTM likely falls into #2 above (I'm not 100% certain as I haven't received the parts yet). It's certainly more serious than a failure of type #1, but there's only so much you can do about this sort of thing. And when the design that failed is identical in principle to the design used in practice by many aftermarket parts and all of the stock parts, it's pretty clear that it isn't a design issue on our end.
So I'm not blowing anything off here. I'm just trying to rationalize what happened to the Vital community before the internet engineers and lawyers overload the servers... I don't think you'll find a company that's any more transparent than we are about our products, engineering, and the occasional failures. And I feel that doing so will actually gain customers rather than scare them away. If you prefer to buy from a company that makes performance claims with any evidence or hides away from their failures, then feel free to do so.
Thanks for the info Billy….Get the torque wrenches out fellas!
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