B737NG first officer reported airspeed and vertical speed issues related to a flaps 25 takeoff.

Attributes
ACN	1584026
Time
Date	201810
Place
Locale Reference	ZZZ.Airport
State Reference	US
Aircraft 1
Make Model Name	B737 Next Generation Undifferentiated
Operating Under FAR Part	Part 121
Flight Phase	Climb
Flight Plan	IFR
Person 1
Function	First Officer Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument Flight Crew Multiengine
Experience	Flight Crew Last 90 Days 274
Events
Anomaly	Deviation - Procedural Published Material / Policy Deviation - Speed All Types

Narrative:

Flaps 25 takeoff caused things to happen quicker than we are used to seeing. Flap retraction altitude and clean-up speeds came fast and caught us off guard. During the flap retraction; the airspeed increased above the 200 knots for under the class B airspace. The airspeed got to about 230 knots and we got a 'don't sink' warning. [We] corrected immediately. We were only above that airspeed for a few seconds.

Original NASA ASRS Text

Title: B737NG First Officer reported airspeed and vertical speed issues related to a flaps 25 takeoff.

Narrative: Flaps 25 takeoff caused things to happen quicker than we are used to seeing. Flap retraction altitude and clean-up speeds came fast and caught us off guard. During the flap retraction; the airspeed increased above the 200 knots for under the Class B airspace. The airspeed got to about 230 knots and we got a 'Don't sink' warning. [We] corrected immediately. We were only above that airspeed for a few seconds.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.