Showa TC bleeding

So I followed the best directions I could find when re-assembling the cartridge, which is to fill the cartridge with oil most of the way, cycle the rod for a few minutes to work out all the bubbles, get the oil level high up near the overflow holes at the top, force the top cap/compression valve down into the oil bath allowing it to push out the excess, then cycling the damper until I'm blue in the face to somehow purge out the rest of the air (how exactly does that part work?). I guess it must just squeeze past the ICS piston o-ring and BV o-ring.

I can still hear a tiny TINY bit of "swishing" inside the cartridge, but get no damping dead spots at all. It does top out a little hard when I'm cycling the cartridge by hand, and comes extended all the way (doesn't stick down any distance at all as if it had some negative pressure). By the book that sounds right. Is it?

I guess since I can't really tell if the compression valve at the top is fully bled or not I'm questioning whether it's purged. I don't really see how it purges other than burping past the o-rings, which seems like a kind of cheesy way to do it.

When you compress the cartridge rod into the cylinder, it displaces oil and any air bubbles trapped in the base piston past the floating IC piston and out the side ports. May sound cheesy, but that's the way to do it.

Remember to leave the cartridges slightly inverted for a short while (10 minutes or so) after purging them to help drain any extra oil out of the spring chamber before assembling the cartridge back into the fork. It gives you a more accurate oil volume.

Looks like I bled it right. Compared it to the other cartridge and the action feels identical.

Now, trying to replace the IC spring on the second damper with a lighter one. When I undid the jam nut on the first damper under the IC spring, the top cap came off the threads easily. On this one, it isn't budging from the inner rod so the jam nut just spins. So does that mean I have to remove all the valving from the other end to get the spring off? Doesn't seem like there is anything else to grab on to if I have the top cap in a vice.

I remember reading somewhere that you had to re-dress the threads if you removed the valving from the base valve? Or was that from the mid-valve? Not that I couldn't do that, but if there's an easier way than going through all that, I'd like to know.

Well, I don't remove the jam nut. Every one that I've seen done that way is hacked up and you have to re-calibrate the length of the stem so that you have the correct number of adjustment clicks.

But, since you've already started down that path........try a little heat from a propane torch on the nut. That'll loosen the locking agent and it should come apart.

The jam nut wasn't a big deal. Do you have a preferred way to do this without the jam nut? Just removing all the valving?

I tried heating it with a lighter with no success. Might try to find an actual torch tomorrow or something.

Thanks for the assistance by the way.

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