With the LX200, there is need to do a fair amount of PEC, in order to get clean images.
There are some pieces of software, like PHD2 (I believe), that suggest that after reading the PE over a cycle of the gears (24 minutes in this case), they can correct for it, to some extent. Possibly I have this wrong, and was in fact hoping one thing, while reading another. Something to do with evening out the FWHM, I think. It's all new to me, having decided to push forward to guided imaging.
Anyway, I stumbled across Buck's Tune Up, by Peterson Engineering. I have a couple of their fixes on my scope already, and they do make things smooooth. So, I placed the order, and in 2 days to goods have traversed the US, originating at Rhode Island, and have just boarded a plane in LA. USPS doing well, so far...
I believe the idea is that they are an insert into the Declination gearing, to take up some slack/diminish the significant backlash between the teeth. I'm not 100% sure right now, but when they arrive, I will advise more clearly.
Vision warning - Bold yellow text on black page alert!
http://www.petersonengineering.com/buckstuneup.htm
From the site:
"Installation of this kit will:
1) improve the drive precision in both RA and DEC drives, reducing or eliminating transfer gear backlash.
2) correct other misaligned drive components, improving drive precision and eliminating the chance of incurring drive damage due to this misalignment.
3) If installed before the scope sees much use - allows you to detect conditions where extended use will seriously damage the scope, rendering the drive/drives inaccurate. We're always hearing back from folks who've discovered loose screws or stripped screws, extra pieces of metal floating around in the gear grease, gears that are only cogging (touching tip of tooth to tip of tooth) instead of meshing, drives that are mis-adjusted, etc."