I've got a full carbon fork (Giant TCR)... without any star-fangled nut inside for tightening the headset... What are my options for a lightweight component to do this that will work well with my carbon steerer?

Plastique cap....with or without USE Ring-go-star.

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Samu @ www.signature.fi

if you are an ultra weight weenie you could:

1) remove your front brake
2) obtain a piece of threaded rod, 2 nuts and 2 washers,
3) tighten the nuts against the washers bearing on the underside of your fork and top of your stem,
4) tighten the stem clamp,
5) remove the rod, nut and washers
6) reinstall brake.

Get the Extralight Ultra Star from Lightbikes.com

It reinforces the carbon steerer beside helping with the top cap

http://www.henryjames.com/

Order the Alpha Q kit. This it the best insurance for a carbon steerer as it completely reinforces the tube. The only downside is it is more or less permanent since you glue it in place.

Be sure to clean the ID of the steerer with sandpaper before epoxying the insert. Wet both surfaces with epoxy, position the insert and let cure upside-down with a greased bolt installed in the nut.

do you have a working URL for lightbikes.com or another place that I can get an extralight ultra star?

I'm not certain that the AlphaQ kit is compatible with all carbon steerer tubes...apparently the wall thickness of the AlphaQ is thinner than some others (which is why they have the flange kit). The diameter of the alloy tube might not fit all steerer tube inside diameters, I'm not sure.

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"Gimondi è un eroe umano, che viene sconfitto ma che continua la sua corsa fino a tornare a vincere." - Enrico Ruggeri

http://www.sales.light-bikes.com/

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"Gimondi è un eroe umano, che viene sconfitto ma che continua la sua corsa fino a tornare a vincere." - Enrico Ruggeri

Alpha Q forks are silly. First you make light fork that has so thin walled stereer that it flex like hell and second you need alloy reinforcement so you could clamp stem to it. If I remember correctly that alloy tube+star weighed ~42g so it's doulble as Rin-go-star (very handy).

Many road forks haven't got hole on bottom on fork so treaded rod can't be used. But you van use normal alloy anchors and take them out after thightening headset. But best solution in to get Stork Stiletto fork, you know what I mean when assembling it. Amaising engineering!



But if you must stay on lower quality forks then Extralite may me nice, only 6g!

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Samu @ www.signature.fi

@ Mr_Potatohead

Great tip on star nut savings. I'm running a Pace RC-31 carbon fork on my mtb. My fork does have a hole in the bottom, so I'll be trying that one out.

I currently run 10mm of carbon spacers and a ring-go-star. If it works, I could lose the 10mm spacer, the ring-go-star and cut my steerer tube to a shorter length.

I was considering shortening my steerer tube anyway. I use my mtb on the road 90% of the time and the aero advantages of 20mm off my front end would also help.

Anyone have a rough idea what 20mm of steerer tub would weigh?

3cm weighs about 10g (carbon steerer), so it will be about 6g + the ringostar and the spacer.

I suppose you could use a big ol' carpenters clamp. I would just be concerned about applying the clamping load eccentric to the centerline of the fork tube.

What are these alloy anchors that you refer to?

Just install expander and top cap and remove it again after adjusting the headset bearings

Alloy Achors...I meaned some sort of expander system that is remoable after use. Not very handy.

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Samu @ www.signature.fi

yeah that's probably a better idea, my idea is actually from the days of press into head tube headset cups. You can use the same principle to install your own headset without the ol' hammer and block of wood.