Primary Fermentation Question

[SirPublius]

I just started brewing a few small batches of pear cider the other day, and I don't have a hydrometer. I'm new to any kind of home-brewing. What's the best way to tell when primary fermentation is done and the cider is ready to be racked?? Is it as simple as when it stops bubbling, or are there other things I should be looking at? I've heard maybe 5-7 days for primary fermentation, but I've also heard other people say they leave their for a few weeks. How do I tell? Thanks.

Oh, BTW, all I did for my recipe was a gallon of pure pressed pear cider, a cup of brown sugar, a campden tab, then after a day my yeast...I know different recipes may take longer or shorter to ferment, but that's what I used.

 

[bendog15]

When your airlock has slowed to 1 minute between bubbles it's time to rack.

 

[SirPublius]

Also, I've heard a lot of people talk in this forum about their recipes going too long, and it turning to vinegar. I thought when the yeast finished eating up the sugar that it was done fermenting and that vinegar was something that happened over a matter of years. Is is the norm to have to arrest fermentation? And what might be a good time to do that if I do? A few weeks after racking? A month after racking?