# SS carbon steerer tube



## SicBith (Jan 21, 2008)

does anyone know the recommended (safe) steerer tube length. I'm riding a stock (uncut) one on a 58" SS and am being told it is unsafe.


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## Dan Gerous (Mar 28, 2005)

For the Evo (but it should be the same or close for the SuperSix), you should have a maximum of 55mm of spacers, including the headset top cap, between the frame and the stem with no spacer above the stem.


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## yamaha46 (Aug 2, 2009)

I saw it recommended to have a small spacer (5mm) above the stem.
I think this is so the whole of the stem clamps onto the steerer/expander, with the spacer giving the gap to tighten the headset.
What do you recon DG? You say no spacer above?

Also do you know how long/deep is the expander plug?


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## Dan Gerous (Mar 28, 2005)

yamaha46 said:


> I saw it recommended to have a small spacer (5mm) above the stem.
> I think this is so the whole of the stem clamps onto the steerer/expander, with the spacer giving the gap to tighten the headset.
> What do you recon DG? You say no spacer above?
> 
> Also do you know how long/deep is the expander plug?


There seems to be contradictive recommendations for spacers above the stem. The Cannondale manuals say no spacers should be above, the mechanics at my store said the opposite and I know some other manufacturers recommend leaving one spacer above...

If you respect the torque (read, don't overtighten) on every bolts and set the expander plug correctly, I don't think it's too big of an issue.

As for the expander plug, it is somewhat adjustable in length on the Cannondale headsets. Cannondale says it shouldn't be set to more than 48mm deep (from memory, check the manual). The idea is to have the expender positioned so it's in line with the stem clamp, so the stem can't crush the steerer.


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## yamaha46 (Aug 2, 2009)

I understand the expander plug sits where the stem clamps on to stop the steerer getting compressed.
I'm getting a caad 10 soon and I will probably want to play with the stem height to find the best place for me.
So can I move the expander plug up and down in the tube to match the stem height?
I've only used headsets on alu forks with star nuts, on those the headset tightness is set be screwing into the starnut.
How do you adjust the height of an expander plug? Does the headset still tighten down onto it?
Thanks.


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## Dan Gerous (Mar 28, 2005)

yamaha46 said:


> I understand the expander plug sits where the stem clamps on to stop the steerer getting compressed.
> I'm getting a caad 10 soon and I will probably want to play with the stem height to find the best place for me.
> So can I move the expander plug up and down in the tube to match the stem height?
> I've only used headsets on alu forks with star nuts, on those the headset tightness is set be screwing into the starnut.
> ...


The expender can move a bit, I don't remember how big a range is possible but yes, it allows a bit of freedom to move the stem to find the correct fit. It's very simple actually.










The expander is made of two parts, the top (black part in the picture above) is the actual top cap but it screws into the bottom one (grey section in the picture above). So you screw both parts together to make it the correct length or correct depth into the steerer. Then you insert the assembly into the steerer and tighten the bottom part to the correct torque specs (with the stem on but not tight). The lower, expanding part can be tighten even with the top part on, it uses a smaller hex size so you can get to it through the top part. Once the expander is tight, you can tighten the top part to adjust the bearing preload just like any other headset with a starnut. Once that's set, align the stem and tighten it. Voilà!

If you want to move the stem until you find the sweet spot, you can actually leave the expender in and just undo the top cap, move the spacers and stem then re-tighten the top cap and the stem, as long as the expender is still properly located relative to the stem.


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## yamaha46 (Aug 2, 2009)

Thanks for that DG. I think I understand how it works now.:thumbsup:
I've been looking for pictures of how it works but could't find anything.


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