Headsets, compression plugs, threadless, what does it all mean?

I just bought a Lightspeed carbon fiber fork, 43mm Rake, 300mm uncut 1-1/8" carbon steerer to go on my Giant Cadex 980c. It currently uses a 1 piece "goose neck" style to attach to the forks. That's all I've ever used so now I'm doing a little upgrading and I need to know if, with this new fork, do I need to go with a new set up? I have done a little research and it looks like I need a new headset, stem and compression plug?
What about brands. cane creek seems like a popular headset and to save even more weight should I go with a carbon stem?

I like to do century riding, long solo rides and it seems like a good idea to save some weight.


Thanks for all your help

Check your headtube size. All the pics I've seen of that bike look like an older 1" threaded setup.

I just called the LBS and confirmed that the original equipment was indeed a 1" threaded fork but the steerer tube is 1-1/8" so I'm good to go on that. I also learned that the "gooseneck" as I called it is a quill stem. Learn something new everyday.
I hate to answer my own questions but I guess I just found most my answers with a phone call. Doh! I should join a local bike club.

That sizing information does not make sense. By definition, the steerer tube outer diameter size is the fork size. A 1" fork has a 1" steerer tube. A frame designed to fit a 1" headset/fork will generally not accomodate the 1 1/8" size.

If you don't believe me, take off the old fork and try to put the new one in. It won't fit. You can use a threadless set up with that frame, but it will have to be 1".

I think you are probably right given the Cadex model. IIRC, some current giant road models use what is called a 1" threaded integrated quill setup which actually involves a 11/8" headtube. He either needs to do some measuring or have someone other than a nose picker look at it.

Is that measurement taken by ID of the steerer tube? The outside of the steerer tube measures over 1-1/4".

Hmmmmmmmm.

There is a riser that my quill neck goes into that goes into the steerer tube, it is slightly smaller. this is the measurement on it. The bottom scale is in inches.
http://miscpics2.homestead.com/caliper.jpg

Not trying to be a pain in the azz, but if you don't know how to measure a headtube, you better let someone more experienced do this or at least supervise. We haven't even gotten into adjusting the headset, cutting the steerer tube, installing a new headset (after removing the mysterious conversion type resulting in a 1/8" reduction). Check out parktool.com for more headset info.

1. The steerer tube is part of the fork. The part of the frame that the fork fits into is the headtube. It appears that you are mistakenly referring to this as the steerer tube. Yes, your headtube outer diameter would likely be over 1 1/4" for that Cadex frame. The fork steerer outer diameter is 1" and that is the key dimension here. The part (riser) that you refer to in relation to the measurement that you provide is probably part of the headset.

2. The headset is fitted into the headtube of the frame and holds the steerer tube portion of the fork in place. The quill portion of the stem is the part that actually inserts into the inside of the fork steerer tube. The inner diameter of a standard 1" fork steerer is 7/8 inches or 22.2mm (which is likely stamped into the quill of the stem). I cannot figure out what your measurement actually indicates.

3. I don't mean to squash your efforts to do this project yourself, but you do not appear to know the correct terms for the different frame and fork parts, and consequently you are confusing yourself and others. Do yourself a favor and take the new fork and your bike to a good shop and let them help you sort things out. They will help you understand the difference between a head tube and steerer tube.

4. It is possible that your frame was built to accomodate a 1 1/8 steerer tube fork and then was fitted with a conversion piece of some sort to allow a 22.2mm quill stem, in which case you may be able to use your new fork. Refer to number 3 above.

I think you may be right. Guess I'll take it in and let the pro's deal with it until I can learn a little more.

Thanks