On doing the steering head bearings....

[SimpleOne]

RDTCU is spot on. Its the cooling (and subsequent contraction of) the weld bead that will cause a captive outer race to drop out of a head tube or hub etc.
If you weld an inner race that has been pressed on to a tube or shaft, its just gonna clamp the thing on even tighter as the weld contracts. To get a race off a tube or shaft, you need try and heat the race and cool the tube/shaft (and hoping that the thermal expansion of the race material is greater than that of the shaft is also a good idea...)

If you have a press, you can actually push the steering tube a little way out the bottom of the lower triple tree, which will in turn push the inner race ice and evenly off the steering tube journal. You can then reverse the process to push the steering tube back into the triple tree at the same time as you are pushing the race back on to the steering tube.

 

[kevinperry]

I changed my steer tube bearings last year .I removed everything...let the bars and controls lay on the tank .I used a small drift to remove the races and they came out easy .I took my lower triple with the inner race to my local shop and had them press off the old inner race and instal the new one ..no charge.The lower outer race is a bit of a bitch to seat ...but it went in smooth after sitting in a ziplock bag in the freezer for 1/2hr .Not a hard job to do and made a huge difference!

 

[Motosportz]

I have done the weld bead on the lower inner race that is pressed on the stem many times. Always worked real EZ. The Weld makes the race expand and it literally drops off.

 

[SimpleOne]

Interesting to hear, that's the reverse of how I used it. The weld definitely expands the race initially whilst applying the arc, but as it cools that bead contracts and compresses the race. Maybe it's a timing thing though, if you're fast enough or have the steering tube inverted, I suppose the race might drop off whilst it's still hot and the steering tube is relatively cold, i.e. before the bead contracts fully. Can't say I've tried it, but I'll take your word for it and give it a shot one day, cheers.

 

[Xcuvator]

Heating anything doesn't make it shrink...

Except water.
It is the weld that pulls the outer race or bushing to a smaller OD not the heat.

 

[Xcuvator]

Interesting to hear, that's the reverse of how I used it. The weld definitely expands the race initially whilst applying the arc, but as it cools that bead contracts and compresses the race. Maybe it's a timing thing though, if you're fast enough or have the steering tube inverted, I suppose the race might drop off whilst it's still hot and the steering tube is relatively cold, i.e. before the bead contracts fully. Can't say I've tried it, but I'll take your word for it and give it a shot one day, cheers.

That is how I think it works too.
I will try it and I think timing is key on inner races.

 

[RDTCU]

Except water.

Well, technically....

And as far as the weld goes, it's more about breaking the bond between the race and the neck tube. The race expands and then contracts asymmetrically due to the weld, so it's then easier to drive out.

 

[Xcuvator]

Well, technically....

And as far as the weld goes, it's more about breaking the bond between the race and the neck tube. The race expands and then contracts asymmetrically due to the weld, so it's then easier to drive out.

Yes I think we are agreeing.