Carbon bars stem type

New to Cycling? Want some advice? Start here...
User avatar
BrindleScoops
Posts: 414
Joined: Mon Jan 09, 2012 21:56 pm

Carbon bars stem type

Postby BrindleScoops » Sun Nov 18, 2012 20:19 pm

So.... I bought a bike recently with carbon bars and when i stripped it down to check everything, the stem had been overtightened and crushed the carbon bars, destroying them. I have a nice sparkly new set to fit, but wondered if you should use a specific type of stem to stop this happening again. The actual clamping force from the stem is across two thin bands in effect and I can help thinking that its a lot of force on carbon bars. I plan to use carbon paste and torque to 5Nm per bolt, will this be OK or am I risking wrecking another bar?
My biggest fear is that should I crash, burn and die, my Wife would sell my stuff based upon what I told her I paid for it.

pinarellokid
Posts: 1128
Joined: Tue Jul 03, 2012 16:06 pm

Re: Carbon bars stem type

Postby pinarellokid » Sun Nov 18, 2012 20:23 pm

just tighten it gradually, go for a ride if it moves tighten it..
i would use this method as then you wont be over tightening it.
Specialized S Works SL2 . Campagnolo Record 11spd. rolling on Campag Zonda wheels

http://app.strava.com/athletes/881211

racingcondor
Posts: 1431
Joined: Thu Jul 30, 2009 17:20 pm

Re: Carbon bars stem type

Postby racingcondor » Mon Nov 19, 2012 12:45 pm

You'll probably be fine at 3-4Nm, do it in stages (1/4 turn per bolt) so that you don't create pressure spots and see how it grips at below the max. You should be fine at 5 but some stem/bar combinations are a poor fit so less is good if it does the job.

User avatar
thegreatdivide
Posts: 4246
Joined: Wed Oct 20, 2010 11:12 am

Re: Carbon bars stem type

Postby thegreatdivide » Mon Nov 19, 2012 13:02 pm

5nm is quite a common torque for carbon bars, stems and posts. All my Ritchey WCS stuff is 5nm, so I bought one of those handy Ritchey torque keys.
"Crevaison sur les paves..."

User avatar
Grill
Posts: 5378
Joined: Wed May 23, 2012 08:27 am

Re: Carbon bars stem type

Postby Grill » Mon Nov 19, 2012 13:14 pm

Keep in mind that when there is only one number published, as opposed to a range, it is the max torque spec. If you can get away with less then you should.
English Cycles V3 | Scott Plasma 3 TT | BMC TrackMachine TM01 | Ritchey Road Logic | Scott CX Team

User avatar
BrindleScoops
Posts: 414
Joined: Mon Jan 09, 2012 21:56 pm

Re: Carbon bars stem type

Postby BrindleScoops » Mon Nov 19, 2012 20:14 pm

All good advice thanks, i just wondered whether a stem with faces that cover the entire surface area under the clamp area would be a good idea, as it just seems you effectively have 2 bands of around 4 mm taking the entire clamping force, but if thats normal, then away I will go and fit them!
My biggest fear is that should I crash, burn and die, my Wife would sell my stuff based upon what I told her I paid for it.

User avatar
Grill
Posts: 5378
Joined: Wed May 23, 2012 08:27 am

Re: Carbon bars stem type

Postby Grill » Mon Nov 19, 2012 22:14 pm

I use a Ritchey C260 stem. Not so much to protect my bars, but because it's light and stiff as hell. Go for it if you're that worried.
English Cycles V3 | Scott Plasma 3 TT | BMC TrackMachine TM01 | Ritchey Road Logic | Scott CX Team


Return to “Road Beginners”

Who is online

Users browsing this forum: No registered users and 3 guests