Sounds like both bikes have carburetor-fuel delivery troubles.. fuel is already restricted... By also restricting air, you get a better air:fuel ratio and the bike sorta runs better . (its called a "choke")
If the Hobbit runs with Starter fluid it tells you the carb is clogged up but ignition is OK. And yeah, the Hobbit carb cannot be removed unless the engine/swingarm unit is allowed to drop away from the frame.
So, a thorough carb cleaning, examination and adjustment on the PA50 is not to be taken lightly.. do it right or do it over.
Disconnect the decompression valve cable at the engine. Disconnect the fuel line to the carb. Disconnect the throttle cable at the carb. (The rear brake cable may need disconnection at the rear wheel) Disconnect the condenser wire at the wire harness bundle near the petcock. The tail light/brake wire bundle is secured to the swingarm with clips so unclip that. Some of the other stuff is clipped onto the swing arm so unclip that stuff too.
Have someone hold the bike steady. Put blocks of wood under the muffler so the engine can only drop an inch or two. Remove the long engine pivot bolt/nut.
Pull the engine slightly forward as you lower the engine an inch or two to rest on the wood block.
Now check for and disconnect anything else that may get stretched or broken when the engine drops all the way to the floor. My memory of my first time is faded.. just take a good look with a flashlight.
Once the engine is resting on the muffler on the ground, remove the 4 reed-block / intake manifold screws and remove the manifold/carburetor as a unit. These screws can be tight and you might want to use a hand impact "wrench" and a sharp tap with a hammer to get them started. A long fat phillips screwdriver may be enough but try not to strip the heads.
On reassembly, use some Permatex 2 non-hardening gasket sealant on the intake manifold mating surfaces to prevent vacuum leaks.
First lift the engine and reinsert the pivot bolt. Now re-route as many cables and wires as possible in such a way as to not interfere with dropping the engine the next time. Or route them as original.. it's up to you.
It is possible to reroute almost everything so that nothing but the throttle cable, decompression cable and fuel line need be disconnected next time around. Clips that hold wires /cables neatly in place are no big deal to attend to.