I get great guiding with my AT130, anything more the .5 RMS is a bad day. What voltage do you run you mount at? It sounds like you might be having a cable snag.? I do run a .8 reducer on my telescope, so it runs at 728mm. Still runs great at the 900mm with no reducer.
Counterweight is now at 1 21Lb all the way up. Here is an old pic of set up from last year. The cable gets looped around azimuth knob when imaging, so never touching ground.
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David Malanick