cutting carbon riser bar

why do you want to cut it?

be /very/ careful - these bars usually have metal reinforcing inserts where the brake lever or bar
end clamps go. if you shorten the bar, these reinforcements effectively become misplaced and you can
crush the unreinforced tube.

if you just want shorter bars, shop around for a different model.

jb

MPT said:

I am thinking to cut a carbon riser bar I recently acquired. I was told that it has to be done
with a special tool . Is it true? What kind of tool is that? Thanks!

Thanks for the reply. I wanna have it cut because it's a bit too wide. "jim beam" <[email hidden]>
wrote in message "]news:[email hidden]...

Quoted message said:

why do you want to cut it?

be /very/ careful - these bars usually have metal reinforcing inserts where the brake lever or bar
end clamps go. if you shorten the bar, these reinforcements effectively become misplaced and you
can crush the unreinforced tube.

if you just want shorter bars, shop around for a different model.

jb

MPT said:

I am thinking to cut a carbon riser bar I recently acquired. I was told

that

Quoted message said:

Quoted message said:

it has to be done with a special tool . Is it true? What kind of tool is that? Thanks!

"jim beam" <[email hidden]> wrote in message "]news:[email hidden]...

Quoted message said:

why do you want to cut it?

be /very/ careful - these bars usually have metal reinforcing inserts where the brake lever or bar
end clamps go. if you shorten the bar, these reinforcements effectively become misplaced and you
can crush the unreinforced tube.

if you just want shorter bars, shop around for a different model.

jb

In all seriousness, has anyone ever crushed or damaged a carbon handlebar?? I've only seen a few
come my way but compared to some of the incredibly sketchy titanium bars of not so long ago (<100g)
where there are no inserts for brakes etc., most of the carbon bars I've seen seem positively
robust! We actually took sample bar from someone (carbon..don't remember which brand..) and beat the
[censored] out of it against a brick wall, putting all kinds of weight and actually jumping up and down on
the bar and it seemed to pass with flying colours. I don't think a Ti bar would have withstood that
much abuse. Now I'm talking about fatigue life as I'm sure a nick or cut in the carbon fibre could
easily propagate into a big failure, but I'm more curious about the short term toughness of carbon
bars. Any strength or fatigue tests online?

Cheers,

Scott..

Quoted message said:

I wanna have it cut because it's a bit too wide.

i got one earlier this year and had the same concerns, but when i looked into the insert situation,
i elected to leave it. now i'm used to it, i'm very happy and am inclined to think the extra width
gives you just a little more control when you need it.

The other reason why I am thinking to the bar cut is because the extra length gave me wrist pain.
This did not happen when I had a shorter/sraight bar. I might try to adjust the bar position for now
then. "jim beam" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Quoted message said:

I wanna have it cut because it's a bit too wide.

i got one earlier this year and had the same concerns, but when i looked into the insert
situation, i elected to leave it. now i'm used to it, i'm very happy and am inclined to think the
extra width gives you just a little more control when you need it.

Quoted message said:

In all seriousness, has anyone ever crushed or damaged a carbon handlebar??

you have a valid point. clearly, some bars are different to others. if you have a component that is
super-thick and has no inserts, you may be ok cutting. but that's not usually the case from what
i've seen. be careful. some of these bars are real thin - hence the need for inserts!

"jim beam" <[email hidden]> wrote in message "]news:[email hidden]...

Quoted message said:

you have a valid point. clearly, some bars are different to others. if you have a component that
is super-thick and has no inserts, you may be ok cutting. but that's not usually the case from
what i've seen. be careful. some of these bars are real thin - hence the need for inserts!

For sure it depends on the bar in question. I cringed whenever I put an 80g Ti handlebar on a
mountain bike. It just seemed a little flimsy to me..I never considered using one myself. And I
actually did stop and think about just how tight I was going to do up the levers on those bikes. The
carbon bars I've seen were not stupid-light bars so that's a sure difference right there. Having
seen other composite parts fail catastrophically (tennis racquets, hockey sticks, golf club shafts)
I wonder if bars would do the same thing. Perhaps Kraig Willet has some bar failure tests online
that I could check out.

Cheers,

Scott..

Scott and Jim, thanks for the discussion. "S. Anderson" <[email hidden]> wrote in
message "]news:[email hidden]...

Quoted message said:

"jim beam" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

you have a valid point. clearly, some bars are different to others. if you have a component that
is super-thick and has no inserts, you may be ok cutting. but that's not usually the case from
what i've seen. be careful. some of these bars are real thin - hence the need for inserts!

For sure it depends on the bar in question. I cringed whenever I put an

80g

Quoted message said:

Ti handlebar on a mountain bike. It just seemed a little flimsy to me..I never considered using
one myself. And I actually did stop and think

about

Quoted message said:

just how tight I was going to do up the levers on those bikes. The carbon bars I've seen were not
stupid-light bars so that's a sure difference

right

Quoted message said:

there. Having seen other composite parts fail catastrophically (tennis racquets, hockey sticks,
golf club shafts) I wonder if bars would do the same thing. Perhaps Kraig Willet has some bar
failure tests online that I could check out.

Cheers,

Scott..

"S. Anderson" <[email hidden]> wrote in message

Quoted message said:

In all seriousness, has anyone ever crushed or damaged a carbon handlebar?? I've only seen a few
come my way but...

<snipped>

Quoted message said:

most of the carbon bars I've seen seem positively robust!

hear hear. I kept seeing mtb custom builds using the new carbon bars, and i would wince away
quietly. however, in the last couple months, we've had a few bits of carbon tube to play with, cut
off the ends of handlebars or bottoms of seatposts. man, they are tough to break. hitting them with
a hammer does little. the hammer generally bounces off, or sends the tube flying. the only way we've
been consistently able to destroy them is with a vice. pretty confidence inspiring, frankly.

we have one dedicated and vocal retro grouch mechanic, and it was a joy to see him try to destroy a
bit of carbon seatpost one day, after a short (and loud) diatribe about its shortcomings and how
delicate carbon is. obviously, the engineering is everything, but this particular seatpost held up
for two or three hilarious minutes of jumping and hammering before he resorted to the 8" vice.

Score it with a razor blade and then use a good quality high tooth per inch count hacksaw blade. Carbon is much stronger than you would ever believe, as long as you don't crush it with a vise.

Eric