[Closed] Installing carbon bars - how tight ?

Get a Ritchey torque key for a tenner, they are ace!

[url= http://www.tweekscycles.com/Product.do?method=view&n=3339&p=98102&c=215&utm_source=Google&utm_medium=Base&utm_campaign=Cycle%20Tools ]Linky[/url]

Before I got my torque wrench, I tightened mine using the short end of the allen key in my hand (to give me the minimum amount of leverage). I'd then check if I could rotate the bars at all & tighten a little more if so.

Then I bought some Renthal fat bars & no longer need to worry.

Then I bought some Renthal fat bars & no longer need to worry.

If you overtorque alloy bars damage would be caused also??

Rusty Spanner

Tips?

Get yourself a flak vest. It's a well known fact that carbon can explode with the force of a giant kicking donkey sending several million razor sharp carbon death stars flying into your spleen. You will be killed.

I bought one of those Ritchey ones a few months ago - ace little piece of kit !

It won't explode, don't worry. Just don't use your bodyweight on a foot long allen key. I'd be more concerned that it seems tight but rotates as you ride - this gives a chance of scoring and delaminating the top layer.

They vary from brand to brand usually in the range of 4 - 6 nm. I do all mine to 4nm and no issues with any slippage

tighten until you hear a cracking sound, then back it off a bit 😉

scuzz - Member

It won't explode, don't worry

The mere fact that you had to say that is proof that it will. It's just good science.

"If you overtorque alloy bars damage would be caused also?? "
IIRC I remember reading seomthing to do with easton and bars dying/snapping early due to overtightened stems

What does your stem say on it? What does their website say? No luck with either, as above I think mine come in mostly 4.5-6Nm (mostly 31.8mm clamp) though I have a couple of 25.4mm clamps which say 9-10Nm on them?

Use carbon paste. (take it you've got it already?).
I've got a big huge torque wrench that a mate borrowed for me from a ship..
Huge big thing but goesdown to 5nm so works fine..

If its really wide ranging then it won't be quite so accurate at the extremes of the torque range?

Most important thing is probably to check for burrs on all edges of the stem/brake levers/shifters that come into contact with the bars and smooth them off if you find any.

As Althepal says Carbon paste will require less torque to keep tight maybe about 3nm

5NM on my carbon Havens.

Carbon paste +2. Tighten them a little less than you think you need to!! Gentle squeeze tight, not hard turn tight!! Save the real grunting tight for bottom bracket cups :-))

tighten until you hear a cracking sound, then back it off a bit

He stole my joke sir.... 🙁

DrP

Huge big thing but goesdown to 5nm so works fine..

+1, I suspect a huge great ship torque wrench is about as accurate at 5Nm as your hand and a whistle in the wind is.

I was amazed how much I was under torquing things when I got my torque wrench. (Sealey 2-24Nm one)

Try torquing up the allen key by inserting the short end into the bolt, placing your thumb under the curve and using your next to last to apply the torque. If you need a bit more also use your middle finger. Fingers act as good torque limiters.

tighten until you hear a cracking sound, then back it off a bit
He stole my joke sir....
DrP

Not to my knowledge - guess we have the same amazing wit 😉

Try torquing up the allen key by inserting the short end into the bolt, placing your thumb under the curve and using your next to last to apply the torque. If you need a bit more also use your middle finger. Fingers act as good torque limiters.

How much torque in NM will your 2nd to last finger give you exactly? 😆

I tighten with the long end of the allen key into the bolt, fingers on the short end. I think it is impossible to overtighten like this unless you hurt your hand in the process. Just tighten it up normally, don't grunt on the key. Not had a bar slip or crack yet.

and also important to make sure the clamp is evenly spaced, i.e. the gaps bwteen the clamp and stem are even...

you can get the torque settings even and still get the gaps uneven...