At 17 mos, most kids 10-13 hours of sleep. She is getting 11 hours at night, she may not feel the need for lots of long naps. This can range, obviously. My oldest slept for 12 hours a night and took 2 naps a day at that age, roughly 1 hour naps. Even at 6, he sleeps about 10 hours a night. My middle one is quite different. He sleeps maybe 8 hours a night if we are lucky and takes a 1 hour, sometimes a 2 hour nap every day at noon or 1pm. He is just wired differently. And my baby (15 mos) sleeps 10 hours at night and takes 2, sometimes 3 naps a day. He gets a total of 14 hours of sleep a day.
I follow their cues, if CJ seems tired before his usual bedtime, we put him down early.
Give her more time to adjust to one nap a day. DD was never a good napper and she went to one nap a day at 12 months. Now she sleeps on average 1 1/2 hours during the day and about 10 hours at night (and she NEVER slept through the night). I'd give her more time to adjust.