Stuck/hard focusing ring on Soviet lens after cla

Hi,

This is my first post on the forum, so I'm hoping I'm posting in the right forum!

So I've recently bought a Kiev 16 c-3, a Soviet 16mm camera with 2 lens turret and both lenses' focusing rings were essentially stuck from gunked up grease. I CLAed the industar 50mm f3.5 but after reassembly the focussing ring gets stuck in two spots and takes a bit of force to focus pasts those spots (which I'm pretty sure were problem spots before the cla too, but I forget to take notes on that), which is a big issue since it's a screw mount and a video camera.
When the helicoid isn't attached to anything it does turn extremely smoothly but as soon as I attach the other parts, it gets harder.
I am pretty new to cla on retro focus lenses (not sure if that's the correct term, English isn't my first language and I don't have any formal training when it comes to this stuff, so feel free to correct me!) and I've only ever worked on a few zuikos, so I only bought one lubricant: em-30L. Is it possible that this lubricant is too thin? I'm asking because the grease inside the lens was quite thick and created pretty long strands when stretched. Or could it be that some part of the lens is slightly warped maybe?
I'd like to add that I did as thorough a job as I could when cleaning the lens (lighter fluid to remove the grease, toothpicks to get in between the thread etc.) and lubricated as liberally as the previous person.

Sorry if I've not been clear enough or if I made mistakes, once again, English isn't my first language
Eager to hear what you people think!

Your lens barrel assembly is probably out of round or slightly egg-shaped and rubbing somewhere.

Imagine two slightly egg-shaped ovals. One is smaller and nested inside the other. Now rotate the outer oval. It will bind each time it hits +/-45 degrees orientation from the starting point.

Look at the gap between the lens focus ring and the barrel of the lens itself. Note any bright marks. Now rotate the focus ring and watch; the lens usually binds on the bright point. It is easier to re-shape the focus ring to a shape that does not bind, than to reshape the barrel. And, it is the most safe, as you might crack lens elements trying to reshape the barrel or make it impossible to disassemble.

I had that problem on a lens once and had to apply gentle, but firm pressure to re-shape it to something that would not bind.

It's not easy and takes time; if that is the issue.

Thank you so much for your reply!

Luckily, the lens elements are attached to the aperture ring, and the move back and forth as a unit (kinda like on a below camera, which makes me realize it's probably not retro focus), so there's no risk there! I'll try to reshape as soon as I'm home.
Btw, little side question: can I try to see if the lens works smoothly without reapplying lubricant every time? I wouldn't want to damage the lens but I also don't have a ton of lubricant left..
Anyways, thank you for the tip and I'll keep you posted,
Cheers!

The slight out-of-round that Kino describes happened to me once, when a strap wrench was used to disassemble a tightly bound lens from its shutter.

After trying what kino said, it works almost perfectly! There's a very slight amount of resistance around the 0.75m but it's almost imperceptible, thank you so much!
As for what Brian said: the camera was far from mint condition when I got it, a metal plate on the side of it was totally warped! Thankfully it serves the same purpose as leatherette would, so approximately warping it back did the trick. So anyway, lenses might have gotten abused too, but everything is good now!

I've started working on the 20mm f2.8 but that one is a bit harder to take apart, especially since the book I have covers the disassembly of the 50mm and just says "roughly the same steps can be applied to the f=2cm".
Anyways, thanks once again for the help and have a nice day guys!