A B737-300 ON TKOF RECEIVED 2 UNCOMMANDED RUDDER INPUTS. ONE AT 80 KTS AND THE SECOND AT ROTATION. FLT DATA RECORDER NOTED 80 KTS INPUT.

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ON TKOF RWY 8 AT ZZZ (WINDS 130 DEGS/10 KTS) WE RECEIVED A GUST LIKE MVR (R TO L) AT 80 KTS; THEN AGAIN AT ROTATION ANOTHER MORE AGGRESSIVE UNCOMMANDED RUDDER PEDAL INPUT REQUIRING PLT ACTION TO MAINTAIN CTL. THE SECOND EVENT; IN THE OPINION OF BOTH PLTS WAS MECHANICAL RATHER THAN ENVIRONMENTAL. AFTER PASSING FL180 THE CAPT (PNF) INITIATED A VOICE PATCH TO MAINT CTLR THROUGH DISPATCH. AFTER A LENGTHY DISCUSSION; DESCRIBING THE EVENT TO MAINT CTLR; IN MAINT CTLR'S OPINION THE EVENT WAS ENVIRONMENTALLY TRIGGERED AND NOT A MECHANICAL ISSUE. MAINT CTLR STATED THERE WAS NO FURTHER ACTION REQUIRED. THE CAPT QUERIED MAINT CTLR AS TO WHETHER OR NOT AN ENGINEERING WRITE-UP SHOULD BE MADE SO AS TO ALERT THE FOLLOW-ON CREW THAT SOMETHING UNUSUAL HAD TAKEN PLACE DURING TKOF. MAINT CTLR SAID 'NO; WRITE-UP FOR GUSTY WINDS ON TKOF WAS NOT REQUIRED.' FURTHER DISCUSSION BY MYSELF AND THE CAPT CONCERNING ALL POSSIBLE CONTRIBUTORS; IE; WIND GUST; FOREIGN OBJECT DAMAGE; TIRE CONDITIONS; AS WELL AS MAIN AND NOSE GEAR ASSEMBLIES; LED US TO THE DECISION THAT EVEN THOUGH WE WERE NOT CONCERNED ABOUT THE SAFETY OF THE FLT; WE WANTED TO DOCUMENT THE EVENT FOR THE NEXT FLT CREW THAT WAS TO ACCEPT THE ACFT. THE CAPT THEN INITIATED ANOTHER PHONE PATCH TO ACR X DISPATCH TO INFORM THAT WE WOULD WRITE UP THE EVENT UPON LNDG AND THAT THE ACFT WOULD REQUIRE A MAINT INSPECTION PRIOR TO THE NEXT FLT. AS A PRECAUTION THE CAPT ADVISED THE FLT ATTENDANTS OF THE INCIDENT AND ASKED THE PURSER TO INFORM THE OTHER FLT ATTENDANTS COMPLETING A 'CABIN ADVISORY.' WE FURTHER INFORMED ATC THAT WE WOULD LIKE THE EMER VEHICLES STANDING BY UPON LNDG AT ZZZ1 IN THE EVENT OF ANY UNUSUAL OCCURRENCE. NO EMER WAS DECLARED. LNDG WAS UNEVENTFUL ON RWY 12R IN ZZZ1. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED NO FINAL CONCLUSION HAS BEEN MADE AS TO THE CAUSE OF THE RUDDER INPUTS. THE RPTR SAID THE FLT DATA RECORDER DID RECORD THE 80 KT INCIDENT.