Jamming slide at full throttle...
 

So, as the title says, my carb is getting stuck at full throttle. The slide has most of its plating intact, but is chewed up in spots - looks like someone has messed up the cable installation process some time in the past.
Some attempt to smooth the slide out using fine steel wool, and while it does move smoothly through most of the range, it tightens up suddenly near the full-throttle position.
Does anyone have a slide for the old rounded-bowl PW20H0V?, or is there anyone with a whole carb for sale?
If I had to, I'd even settle for a C95 carburetor.

Your throttle slide may or may not be a cause for sticking, unless you know for sure. I had a throttle stick on one of my CA95's and another CA95 owner had the same issue.

Please check your throttle slide at the handlebar. Is the cable slide (that the throttle cable attaches to) mushroomed on the underside? Is there and rust --OR GREASE- inside the throttle tube?

The mushrooming can be filed down and polished with 000 steelwool. Clean the throttle tube and re lube with 3 in 1 oil or a gun oil...NO GREASE.

Check out these things before changing slides or carb.

Thanks for the advice.

The throttle control and cable were just fine, the slide was actually getting stuck, irrespective of the cable...
Good news though... I think I may have worked it out. I happened upon http://www.thevincent.com/vincarb.htm
and found an interesting method for un-sticking a slide after normal methods have failed. Basically, give the bore a slight squeeze in various locations, and if the slide moves freely, then a very little bit of work with the channel-lock pliers on the same area frees up the slide movement.
I've reinstalled it on the bike, and it seems okay so far. I'm going to let it sit overnight and I'll see how it is tomorrow.

Great Read! I would not have thought of lightly squeezing the slide chamber. Although caution doing so is the key. Hope it is the answer!

It's alive!
Slide is working great now, no jamming. The fresh rebuild seems to agree with the carb, as the bike's responding more easily to throttle and starts up much easier. Happy time! :):):)

Ooooo interesting! I'll have to give this a thorough read this weekend.