Hi , I have a GSO 10 to 1 on my ED80 and its been there now for about 4 years .
right from day 1 it was usable but not very smooth in use .
After about a year I had, had enough of this feel as no amount of adjustement would make it feel nicer , or smoother , oh yes it was smooth without a diagonal or eyepiece fitted but as soon as a little weight was added it felt horrible
( not as bad as my 127 triplets focuser , but close , I now have a FT3035 R&P on that scope , but thats another story ) ,
so I spent a little time playing around with the adjustements and changed the goop the chinese use for grease and that helped a bit , but it was to fiddly to get right and the smallest knock caused it to revert back to the grumbler !! .
In the end I replaced the 3 ball bearings that it was made with , and what a joke these are , mild steel and non hardened !!!
no wonder it was not smooth.
A quick measuire up and I found a NGN ball race with the same sized , accuratly sized , hardened balls , those with white lithium grease made the feel very good with my lighter eyepieces , but with my Naglers and humongous
celestron Axiom LX31mm the grumbles returned , bugger !!
Then I found this little gem of info on the net . I cant remember where but here it is for all to see..
Rub candle wax into the shaft where the top rollers run and then down the bottom where the focus knob runs ,wind it in and out rub some more , use pressure , dont be shy , in and out a little more , wipe off the axcess and WOAW !! the grumbles are gone I could not bieleve the feel , almost as good as the FT .. well almost but what a differance a little candle wax made .
Give it a go if you have one of these GSO's it is well worth it .
Brian.
, alt / az mount movements ? , thanks but it works very well on crawford focuses as well , I hope a few owners give it a go its a good fix. 
Still good Silv , yep the movements are still smooth , if it does return to grumbles again its cheep and easy to put some more in .
