Mountain Biking - I think I just ruined my new carbon handlebars...

I just replaced my 10+ year old alloy Zoom bars with some Answer Hyperlites (carbon). My old handelbars were fairly light weight aluminum and had been in one pretty severe crash, so I didn't really trust them. My stem doesn't have a removeable faceplate, just the old style single bolt clamp. When I first began to slide the bar in, I noticed the clamp opening was a little too small. No big deal, I thought, this is almost always the case when I have replaced handlebars. So I used a flathead screwdriver to open the clamp a little (it's aluminum) but the bar still wouldn't budge. I opened the clamp as much as I could and the bar finally went in, but it was a very tight fit. Then I noticed a nice scratch in the stickers on the front. That wouldn't really bother me but the scratch appears to begin ON a bare carbon section. :( I really can't tell if it's just a scratch or an actual gouge. Now, I'm not hard on my handlebars at all, in fact I rarely even stand and pedal. No jumping or drops, just occasional wheelies. However, I've always heard that even very minor damage on carbon fiber bars can render them unsafe, so naturally I'm concerned. So now I trust my brand new handebars less than I trusted my ancient alloy ones. :(

Look closely and make sure it's not a hairline fracture through the bars, if it is then you might have to replace the bars.

I just replaced my 10+ year old alloy Zoom bars with some Answer Hyperlites (carbon). My old handelbars were fairly light weight aluminum and had been in one pretty severe crash, so I didn't really trust them. My stem doesn't have a removeable faceplate, just the old style single bolt clamp. When I first began to slide the bar in, I noticed the clamp opening was a little too small. No big deal, I thought, this is almost always the case when I have replaced handlebars. So I used a flathead screwdriver to open the clamp a little (it's aluminum) but the bar still wouldn't budge. I opened the clamp as much as I could and the bar finally went in, but it was a very tight fit. Then I noticed a nice scratch in the stickers on the front. That wouldn't really bother me but the scratch appears to begin ON a bare carbon section. :( I really can't tell if it's just a scratch or an actual gouge. Now, I'm not hard on my handlebars at all, in fact I rarely even stand and pedal. No jumping or drops, just occasional wheelies. However, I've always heard that even very minor damage on carbon fiber bars can render them unsafe, so naturally I'm concerned. So now I trust my brand new handebars less than I trusted my ancient alloy ones. :(
i would use them...you sound gentle with the bike. if it implodes, i think you'll make it

was it an over sized bar??

i would use them...you sound gentle with the bike. if it implodes, i think you'll make it

was it an over sized bar??

Non-oversized. I'm going to go look at it again very closely to see if I can tell if it's very deep or just a scratch...

Ok, now I'm seeing what may be a hairline fracture. The thing is, I barely even tightened the stem clamp. It was basically just tight enough to keep the bar from rotating. But I can't tell for sure that it's a fracture, because there's a scratch next to it that looks similar, except to one end of that one you can tell it's only a scratch. This one looks the same along it's length. Surely these handlebars aren't that fragile!

Ok, now I'm seeing what may be a hairline fracture. The thing is, I barely even tightened the stem clamp. It was basically just tight enough to keep the bar from rotating. But I can't tell for sure that it's a fracture, because there's a scratch next to it that looks similar, except to one end of that one you can tell it's only a scratch. This one looks the same along it's length. Surely these handlebars aren't that fragile!
mount them...then push down on them and in different directions to see if you can cause it to break or any problems. kind of like my orthodontist pushing excessively in all directions on my brackets to see if they are likely to break off before i leave the office :D

mount them...then push down on them and in different directions to see if you can cause it to break or any problems. kind of like my orthodontist pushing excessively in all directions on my brackets to see if they are likely to break off before i leave the office :D

:lol: On one hand, I don't want to break them, but on the other hand, it would be better to break them in my workshop than while sprinting or something. :lol:

:lol: On one hand, I don't want to break them, but on the other hand, it would be better to break them in my workshop than while sprinting or something. :lol:

yeah, so very true. if you can't break them now, then i think they'll hold up to a wheelie or two. after, well...good luck with that. be sure to update us

Ok, now I'm seeing what may be a hairline fracture. The thing is, I barely even tightened the stem clamp. It was basically just tight enough to keep the bar from rotating. But I can't tell for sure that it's a fracture, because there's a scratch next to it that looks similar, except to one end of that one you can tell it's only a scratch. This one looks the same along it's length. Surely these handlebars aren't that fragile!
You made a big mistake by using a one piece clamp. Controlling the pressure (and roundness of the clamp) is extremely difficult with those models. Also the fact that you had to jimmy the clamp open attests to it being out of round. The bars are FUBAR. Time to join us in the 21'st century and get a removable faceplate stem. Even then you will most likely have to bust out the Dremel and properly chamfer the edges so that they don't dig in to the bar.
Bar manufactuers give you instructions for a damn reason and it ain't to fill garbage heaps. Try following them next time

The bars are FUBAR.
Agreed.

Thanks for the advice. Granted, the instructions didn't mention a single word about using only removable faceplate stems, but I guess I'm supposed to know everything. :rolleyes: As a matter of fact I followed the directions precisely, even removing any burrs on my stem and shifter clamps.

Edit: At least I thought I removed all the burrs. I worked on it for quite a while until I couldn't detect any. *shrug*

It was likely the out of round causing an uneven pressure load that killed you.

The bars are probably fine. Ask a shop if you're scared.. no one can make a valid assessment over the internet. Carbon fibre is tolerant of small surface scratches. I have a older carbon bar that's scuffed up from different stems, including my old Syncros clamp-style stem, I still use it. I snapped a zoom aluminum bar back in the day too.