Slowman wrote:
you'll note that this frame, in front of the head tube top, where the steerer exits, slopes up. this is okay if you use the factory stem, or a stem that follows this profile. but as you can see even the factory stem is built to really hug that profile. in my opinion it would be a mistake to try to use this bike as a long/low bike beyond the longness, lowness it currently exhibits.To be clear, I would never have bought this bike if it didn't work for me from a pad x and pad y perspective with stock parts. Which I did.
I don't know what the cause of this was, but it wasn't a one shot deal. Like I said, we tried three stems and two different forks, and it just didn't work. Like Jeroen, I also shaved off threads from the pinch bolt.
My sense is that it's an issue with the single pinch bolt combined with the heft of the stock stem (and the tolerances between stem and steerer). I almost guarantee that a normal stem with two bolts and a standard carcass/body to it would have held pat.
Let me clarify my comments about how I ride differently than most people. I don't know anyone else who rides like that on the types of roads I ride in the configuration I ride. And yes, I ride in the lowest and longest stock configuration that this bike allows and provides for, and I ride very steep. But beyond that, like I have said, I put my elbows directly in the center of the pad. When I hit road turbulence, it hurts like a bastard on my elbows -- routinely, my pads break the skin at my elbow. So when I'm going 40 mph and I'm about to hit a storm hole cover I lift my elbows off the pad, and all the weight of upper body, which remember is very far forward, essentially falls on the tip of the extension. So there isn't distribution to the pads in these cases. That's a long lever, and I have a long cockpit. Yes, theoretically there shouldn't be horizontal force, but in practice there is uneven force applied. Occasionally -- for instance, if I'm texting or taking a selfie or something -- I may put a bunch of weight on one extension only, or one side of the cockpit only.
Additionally, the roads in and around the city of Philadelphia, where I do a big chunk of my riding, are utter garbage. I also get biweekly flats, even with tubeless setups with excessive sealant. Just because you flat twice a year on the same tires doesn't mean I'm doing something wrong with my tires.
All this is admittedly an extreme and unusual way of riding, and to be clear I don't think others will have this same issue, nor should they avoid buying this bike solely of my specific product issue. This post was primarily about the aftermath of all that, even as Diamondback worked with me to diagnose the product issue and in the attempts to fix it.
The way I ride notwithstanding, this shouldn't happen, which is why I sent it back and asked for a refund. The bike simply didn't work for me. It works for Jordan. It works for Dan. It works for Jeroen. It'll likely work for others, especially if DB ever gets their act together with the stem and front end.