Is this too cheeky to ask?

This - 3-4 times visiting an old pony in a year is a lot and I would probably have started to feel put out now if I was the new owner.

Oh, I didn't think that was too bad, 3 or 4 months in between visits? Probably best to walk away then.
 
Why not write them a letter and explain what you would like to do and that it would only be infrequently etc.? Also say you will not be upset if they say no and hope that if that was the case you could still go and see the horse. By writing you are not putting pressure on them to make a decision on a matter they may not have considered or making them feel obliged to say yes. You can also carefully consider and craft what you want to say and avoid the potential of a flustered conversation.

From a personal perspective I would happily say yes to the previous owner riding one of mine but not the other; it very much depends on the horse and the person you bought it from imo.
 
It wouldn't even be infrequently, I just wanted one last ride. However, having thought about it, I think Hash Rouge is right and I should just walk away. If they ever do offer then I will accept but if not I'll just leave it be an concentrate on my share :)
 
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