So it's not that I don't believe that carbon products - particularly products like rims and handlebars that are not bonded to unlike materials - can't be made both stronger and notably lighter than the equivalent aluminum products. Money aside, I have no concerns running carbon bars as long as maximum stiffness isn't a design goal.
I can't remember the last time I've seen a broken aluminum MTB handlebar but I have also seen a few broken carbon bars a year for the last few years. I wonder if it doesn't come down to two things:
1) Carbon bars seem to exist in two states: perfect and broken. They don't bend, they don't dent and they actually hide scratches pretty well. An aluminum bar that's put through identical abuse will scream "REPLACE ME!!!" where as a carbon bar will likely still look saleable (NEVER buy a used carbon bar! Actually, used stems and handlebars are probably best avoided).
2) The initial investment and replacement costs of most carbon bars is so high that riders are reluctant to replace them if they "look fine" even if (as Andy notes) retiring critical components before they actually reach their end of life is probably best practice. It maybe sounds harsh but if someone doesn't have the money to replace their carbon bar after a huge digger (regardless of how it looks) it's probably better to buy three aluminum ones.
A good (bad) example is a customer I had that cracked the arch on a set of Fox 40 lowers (incredibly rare), bent the crowns and cracked his direct mount stem in a massive crash. He replaced all of those parts but not his Easton carbon bar because it "is totally fine and I've never heard of one breaking".
They are also much for susceptible to cracking from over-torquing of the stem clamp or controls. A torque wrench is the cure in either case (or leave controls loose enough to spin in a crash and solve two problems in one) and 35mm takes it a step farther by making the bars less susceptible to user inflicted damage.
Dec. 22, 2017, 11:30 p.m. - Andrew Major
So it's not that I don't believe that carbon products - particularly products like rims and handlebars that are not bonded to unlike materials - can't be made both stronger and notably lighter than the equivalent aluminum products. Money aside, I have no concerns running carbon bars as long as maximum stiffness isn't a design goal. I can't remember the last time I've seen a broken aluminum MTB handlebar but I have also seen a few broken carbon bars a year for the last few years. I wonder if it doesn't come down to two things: 1) Carbon bars seem to exist in two states: perfect and broken. They don't bend, they don't dent and they actually hide scratches pretty well. An aluminum bar that's put through identical abuse will scream "REPLACE ME!!!" where as a carbon bar will likely still look saleable (NEVER buy a used carbon bar! Actually, used stems and handlebars are probably best avoided). 2) The initial investment and replacement costs of most carbon bars is so high that riders are reluctant to replace them if they "look fine" even if (as Andy notes) retiring critical components before they actually reach their end of life is probably best practice. It maybe sounds harsh but if someone doesn't have the money to replace their carbon bar after a huge digger (regardless of how it looks) it's probably better to buy three aluminum ones. A good (bad) example is a customer I had that cracked the arch on a set of Fox 40 lowers (incredibly rare), bent the crowns and cracked his direct mount stem in a massive crash. He replaced all of those parts but not his Easton carbon bar because it "is totally fine and I've never heard of one breaking". They are also much for susceptible to cracking from over-torquing of the stem clamp or controls. A torque wrench is the cure in either case (or leave controls loose enough to spin in a crash and solve two problems in one) and 35mm takes it a step farther by making the bars less susceptible to user inflicted damage.