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Edited Date/Time
4/16/2022 7:23pm
Did anyone see or find out what happened to his bars?
Was it the bars or clamps or what? Any pictures?
Was it the bars or clamps or what? Any pictures?
The Shop
Garrett runs solid aluminum cones instead of rubber, plus a 4mm bar riser, which puts a lot more load through the bolts than a standard setup (rubber cones and no riser). That, combined with the bike hitting just right, did them in. It’s one of those situations, where, if you crash hard enough, something is going to break.
The bolts themselves are high quality, grade 5 titanium, with rolled threads, and installed such that the shear plane is across the bolt shank (not the threads). It's basically the best it can get from a bolt strength standpoint. We have thousands of these bolts in use right now and last weekend was the first time we've had any breaking. They're not a new batch, a new material, or anything out of the ordinary; they're the same as all the others out there, it was just a freak incident. And to be clear, it was the crash that caused the bolts to break, NOT the bolts that caused the crash (it’s clear from the video taken by Club MX).
We all understand shit breaks now and again, especially in such extreme use.
Here's a screengrab of the crash as the bars hit the ground. Note how deep they get buried into the face of the single (past the grip). That put a huge load on the bolts, which is why they failed.
It's easy for this to turn into a thread where people leave thinking the product is bad, but the reality is that it was just a freak crash in combination with a setup that very few people are using (aluminum cones and bar risers).
And he didn’t sound defensive at all.
It's easy to design something that will never break, but your design will end up really heavy. When you're making high end parts, that's not acceptable. So we compromise to make the lightest parts we can that hold up to regular use and reasonable crashes. That's how we end up with the lightest high performance triple clamps available.
If this were all really a design problem, you'd see it happening a lot more often. We just happened to have some huge crashes at Daytona.
Pit Row
Grade 5 titanium is stronger than a grade 8.8 steel bolt, so there's no point in switching it out for that. Going up the ratings, a 10.9 bolt is only about 8% stronger than the titanium bolt, but slightly more brittle, so no big benefit there.
But if you go up to a 12.9 bolt, then you're about 30% stronger (though more brittle than the titanium), which may help in some crashes. The steel bolts won't bend much instead of breaking, especially in Garrett's crash (tensile failure) and even if they did, I wouldn't want anyone riding on them further as that would be a dangerous situation itself.
The grade 12.9 steel bolt will be a little stronger and could save a DNF in some crashes vs. the titanium bolt. I don't think it would have mattered much in Garrett's crash as everything aligned just right to put all the load in the bolts in tension. And in Julien's case, his crash was so huge that even if the bolts didn't fail, he wasn't going to keep riding as his leg was broken.
One thing about the steel bolts is that they're more resilient to torque variation. It's easy to over-torque a titanium bolt if you're in a hurry, aren't using a good torque wrench, have the wrong anti-seize, or similar; and that can put either too much or too little clamping load on the assembly. Most of the mechanics are pretty good about getting the torque right, but sometimes they can forget, or are in a rush to get the bike done. And that can lead to problems on it's own. So in that case a steel bolt can be "better". But it also weighs about twice as much as the titanium option, so again, it's a compromise.
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