What will probably break first?

[Capricorn]

bars and stems are not made equally. the safety factor is higher on a stem. Most bars with the proper defect will fail suddenly because of the loading on them, aka you, and the fact they are nearly wafer thin. Check that 2nd photo of Frail's. Not hard to imagine where the failure started and why.

[Lucky Luke.]

eh, you guys have me worried now... I have had a KCNC Fly Ride Stem on my MTB for a while that has been creaking, the bolts also loosen themselves, not to mention the gap where between the stem tightnening section where it tightens around the steerer seems to be smaller than ever (implying that the aluminium has maybe deformed slightly). I have long suspected it might fail but assumed that there must be huge safety factors on these things.

 

Nope, my flyride stem on the road bike lasted 6 weeks before it cracked.

[Goodbadugly]

Why buy stuff with a bad reputation like kcnc in the first place?

[Lucky Luke.]

Why buy stuff with a bad reputation like kcnc in the first place?

 

It's light and cheaper than other light stuff. And it has some bling value too.

 

If you're heavier than most like me, I think it's best to use the stuff that is less likely to fail, or just less likely to lead to injury when it does: chainring bolts, skewers, derailleur pulleys etc.