How to install my J&L extra-light headset expander?

[J00P]

Help!
I just got a light expander of ebay, (J&L extra light star-nut-fit expander) but installing seems not a straight forward as expected.


I thought I could install it, just using my carbon topcap and a screw. However, in that case tightening the srew on top only moves the expander up, it does not expand!


Anyone here knows how these expanders should be installed? Here's a last "exploded view" picture:


Thanks for any advice!

[kode54]

i make the tension so that i have to press it in tightly into the steerer tube...with enough friction that allows me to move it down slightly into position, then use the correct allen wrench to tighten it up. cinches pretty tight...and works well.

[glepore]

It installs like any other expander-thread the two sections together, then use the appropriate allen in the expander itself to secure it to the steerer before putting the cap/bolt in place. The J&L piece won't take too much torque before it fails, fyi.

[clm2206]

My two cents on these expanders is that they are a risky piece of equipment. If you're planning to install this expander in a ww bike that will be barely ridden, go ahead, but if you race, forget it. The expander should have at least the stem height, to ensure even and proper tightening surface to the stem, otherwise you can get different gaps in the lower and upper stem steerer side bolts, and that's a sign of hazard.

[trex021]

The J&L expander is a copy of the Extralite Ultrastar. The issue you're having has been documented by others here in the past viewtopic.php?f=3&t=131134

[HTML]

J00P, Its not meant to expand when you tighten your carbon top and bolt. It has its own hex which is seperate. First you tight that inside the steerer. Place it in and set it around 20mm or so below the top of the steerer. Tighten the top piece (carefully otherwise you may push it further down the steerer) Once snug. You then fit your stem,carbon top cap and bolt.

You will need an 8mm hex key to tighten it. The piece with the hex shape cut out is the top piece. Tighten that into the lower piece. And the rings and rubber band in between will expand. Pretty simple really.

I have the Extralite Ultrastar. Been using it for 4 years no problems.

[J00P]

Thanks for the clear discription, it makes sense! I'll try installing it that way.
Plan is to fit it to my crosser/gravel bike. Hope it's not gonna break!

[mdeth1313]

Make sure your wrench is seated squarely before you tighten that bolt and you apply even (perpendicular) pressure - they can strip very easily.

[arizonahalfnhalf]

Yes these things are a massive pain in the ass. Worse to get out than put in, I usually had to rotate my bike stand so my bike was upside down and let it fall out.

If you get lucky and get the tension JUST right, you can get it to slide out without falling down the steer tube.

My advice is to tension the headset with a normal compression plug, tighten your stem, and then remove the compression plug and install this one with your top cap.

[eric01]

Use a heavier duty / easier to use expander to do initial setup and preload headset. Once you have your stem tightened up, remove the heavier one and replace with a lightweight bung like this. If torqued up properly (and w/ carbon paste), the stem will do the job of keeping everything nice and snug and the light weight top cap & bung is there more or less for cosmetics.