Starbucks' (SBUX) is maintaining momentum after "fundamentally strong" fiscal Q3 results, though questions remain about how long that strength can persist, RBC Capital Markets said Thursday in a report.

Starbucks raised its full-year guidance on Wednesday after Q3 revenue and earnings topped expectations. The company is accelerating store remodels, with revamped locations showing transaction growth across formats and customer segments, the report said.

Operational metrics, including store ranking, service speed and food availability, showed improvement, and the rewards program is tracking ahead of internal expectations, RBC said.

Still, Starbucks faces potential for further North America store closures, and full-year guidance implies limited upside for Q4 EPS, the report said.

RBC raised its price target on Starbucks stock to $115 from $110 and maintained its sector-perform rating.

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