How would stiff focus affect the value of a lens?

[Victor Nguyen]

I bought a Kiron 105 for $200 just to find out that it has stiff focus in some parts. How much do you think I can sell it for? Or should I try to re lube it myself?

[iangreenhalgh1]

Kirons are notorious for lubricant problems, often it liquifies over time and drips onto the aperture blades, causing them to stick.

[Lightshow]

If you've worked on a lens before, it shouldn't be that hard...
Now, if you plan to do a complete disassembly, just make sure that you scribe some marks to make it easy to put back together, I usually make a set of marks @ infinity to confirm I put it back together correctly, then I make a set of marks where the helicoid comes apart to make it easy to find the correct alignment.
A tooth brush, cloth, solvent and soap is needed(for how I clean mine) the cloth removes the bulk of old lube, solvent and brush to clean all the threads, then repete with soap and water, then dry, relube and assemble it.

If you don't feel comfortable taking it completely apart, you may be able to get access to the helicoid threads to wipe the old grease away, then relube it, the main issues will be that what is causing it to be tight may not be cleaned away, also, the old and new lube may not play well with the new lube, an option is to soak the helicoid in a solvent to remove the rest of the old lube, just don't work the helicoid too much with no lube, with this method you have to be sure the helicoid is dry before you relube or the solvent will degrade it.

If you've never worked on a lens before, then I urge caution, as not everyone is capable of doing this

[Victor Nguyen]

I don't think I want to risk it. I'm just gonna sell it then. How much do you think I can sell it for? I didn't know that Kiron is notorious for lubrications problem.

[Attila]

Don't touch sell it, 250 USD I think will be fine for sale price.

[Victor Nguyen]