Torque For Carbon Steerer?

Location
Loch side.
First set of full carbon forks I've had, I'm guessing about 4Nm for the stem bolts?
Yes
Also make sure the steerer is LONGER than the stem and headset assembly and you have a spacer on top of the stem to make the steerer appear shorter, if you get what I'm saying.
 
My forks said 10 Nm max so I'm using about 6 or 7 Nm.

What @Yellow Saddle is saying is important so that the top cap is actually not pressing on the steerer but on the stem. Mine is about 2mm below the top of the stem and with a 5mm spacer above that.
 
Location
Loch side.
My forks said 10 Nm max so I'm using about 6 or 7 Nm.

What @Yellow Saddle is saying is important so that the top cap is actually not pressing on the steerer but on the stem. Mine is about 2mm below the top of the stem and with a 5mm spacer above that.
No, I'm saying the opposite. I'm saying, for carbon forks, the steerer should be LONGER and the space you need for adjustment should be added by putting a spacer on top. In other words, the top cap presses on the spacer that presses on the stem.
This is to prevent the steerer from crushing at the end, along the stem's vertical split line.
 
No, I'm saying the opposite. I'm saying, for carbon forks, the steerer should be LONGER and the space you need for adjustment should be added by putting a spacer on top. In other words, the top cap presses on the spacer that presses on the stem.
This is to prevent the steerer from crushing at the end, along the stem's vertical split line.
Well, I followed the instructions for the forks and I have them on my laptop.... will post them when I get home.

Reading your post again and the cap, on my setup, presses on the spacer which presses on the stem.... as you said. The difference is on the steerer being longer but the instructions I had said to cut the steerer 2 or 3 mm shorter.
 
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Location
Loch side.
Stem stack.jpg
Well, I followed the instructions for the forks and I have them on my laptop.... will post them when I get home.

Reading your post again and the cap, on my setup, presses on the spacer which presses on the stem.... as you said. The difference is on the steerer being longer but the instructions I had said to cut the steerer 2 or 3 mm shorter.
That is valid for aluminium steerers but carbon doesn't compress the same as aluminium. If you compress the end of a carbon tube, it collapses, whereas an aluminium tube doesn't. The collapse isn't always immediate, but it deteriorates with time as the continuous stem movement breaks up the resin matrix.

This photo explains what I mean.
 
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I am Spartacus

Über Member
Location
N Staffs
Depends on the headset and forks.. for a Cannondale Caad and methinks SuperSix, you can get away with slamming the top cap onto a carbon fork without a disaster occuring.
285648d1377249990-flipping-stem-over-cannondale-7170011986_8bdc06f285_o.jpg


As per the diagram example shows max number of spacers underneath (for the infirm) but none required above.
Requires a steady hand in cutting the steerer correctly.
If I am about to die, please advise
 
OP
Smokin Joe

Smokin Joe

Legendary Member
Yes
Also make sure the steerer is LONGER than the stem and headset assembly and you have a spacer on top of the stem to make the steerer appear shorter, if you get what I'm saying.
I've already cut it slightly shorter than the stem, but not as much as I intended as it is only a mm below and I had to use a 5mm spacer on top to prevent the bung bottoming on the steerer, Is it ok like that?
 
Location
Loch side.
Depends on the headset and forks.. for a Cannondale Caad and methinks SuperSix, you can get away with slamming the top cap onto a carbon fork without a disaster occuring.


As per the diagram example shows max number of spacers underneath (for the infirm) but none required above.
Requires a steady hand in cutting the steerer correctly.
If I am about to die, please advise
I think you are fine. In your case the compression assembly saves your bacon. If you look at it, you have a long close-fitting aluminium insert that goes down into the steerer and supports it against the stem's compression. However, if you look at some of the compression assemblies, they don't have that part. Then your best bet is to ensure that the bottom expanding part of the assembly as shown in your diagram, is as close to the top as possible. By that I mean, a long bolt can easily allow the expander to hang 10mm below the top of the steerer. Make it ride high instead.

@Smokin Joe, this should answer your question as well.
 
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Location
Loch side.
Depends on the headset and forks.. for a Cannondale Caad and methinks SuperSix, you can get away with slamming the top cap onto a carbon fork without a disaster occuring.


As per the diagram example shows max number of spacers underneath (for the infirm) but none required above.
Requires a steady hand in cutting the steerer correctly.
If I am about to die, please advise
And....don't call me infirm.
 
Location
Loch side.
As promised, here are the instructions for the forks with carbon fibre steerer.

You need to look at the second column, heading CUTTING THE FORK STEERER TUBE
The subtlety there is the use of a Spez proprietary expander. Just look at how long it is. That will keep you safe. If you don't have one, don't do it like that.
 
OP
Smokin Joe

Smokin Joe

Legendary Member
Right, so shifting the 5mm spacer from above the stem to below and moving one of the 10mm above the stem the steerer is now above the stem. I've got a total stack height of 41mm and the top of the bung is about 9mm below the top of the steerer. How does that sound?
 
Right, so shifting the 5mm spacer from above the stem to below and moving one of the 10mm above the stem the steerer is now above the stem. I've got a total stack height of 41mm and the top of the bung is about 9mm below the top of the steerer. How does that sound?
Trying to visualise "and the top of the bung is about 9mm below the top of the steerer" and and moving one of the 10mm above the stem. The way I see it I wouldn't ride that but that it's just my opinion.
 
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