I know this might be very obvious but I’m going to share this method anyways.
If you’d like to achieve some polyrhythmic action on the op-1 it actually is possible eventhough the only Tupper ratio in the sequencers are triplets.
First you’ll need to record a drum track with your first pattern, take 1 bar of sixteenth notes for example. Now if you want to have a 4:5 polyrythm all you need to do is to divide your original BPM by the tuplet you want to add.
So if our original BPM is 90 we’ll end up with 18.
Now we add this number to our original tempo and when playing back the sequence again you should have achieved polyrhythm magic.