diff --git a/boostmovehub.ts b/boostmovehub.ts
index cc03636..3aac515 100644
--- a/boostmovehub.ts
+++ b/boostmovehub.ts
@@ -61,6 +61,7 @@ export class BoostMoveHub extends LPF2Hub {
         if (portObj.id !== "AB" && speed instanceof Array) {
             throw new Error(`Port ${portObj.id} can only accept a single speed`);
         }
+        portObj.cancelEventTimer();
         return new Promise((resolve, reject) => {
             if (time) {
 
@@ -82,11 +83,12 @@ export class BoostMoveHub extends LPF2Hub {
                     // @ts-ignore: The type of speed is properly checked at the start
                     const data = Buffer.from([0x81, portObj.value, 0x11, 0x51, 0x00, this._mapSpeed(speed)]);
                     this._writeMessage(Consts.BLECharacteristics.LPF2_ALL, data);
-                    setTimeout(() => {
+                    const timeout = setTimeout(() => {
                         const data = Buffer.from([0x81, portObj.value, 0x11, 0x51, 0x00, 0x00]);
                         this._writeMessage(Consts.BLECharacteristics.LPF2_ALL, data);
                         return resolve();
                     }, time);
+                    portObj.setEventTimer(timeout);
                 }
 
             } else {
@@ -125,8 +127,10 @@ export class BoostMoveHub extends LPF2Hub {
      * @returns {Promise} Resolved upon successful completion of command.
      */
     public rampMotorSpeed (port: string, fromSpeed: number, toSpeed: number, time: number) {
+        const portObj = this._portLookup(port);
+        portObj.cancelEventTimer();
         return new Promise((resolve, reject) => {
-            this._calculateRamp(fromSpeed, toSpeed, time)
+            this._calculateRamp(fromSpeed, toSpeed, time, portObj)
             .on("changeSpeed", (speed) => {
                 this.setMotorSpeed(port, speed);
             })
@@ -151,6 +155,7 @@ export class BoostMoveHub extends LPF2Hub {
         if (portObj.id !== "AB" && speed instanceof Array) {
             throw new Error(`Port ${portObj.id} can only accept a single speed`);
         }
+        portObj.cancelEventTimer();
         return new Promise((resolve, reject) => {
             portObj.busy = true;
             let data = null;
@@ -183,11 +188,12 @@ export class BoostMoveHub extends LPF2Hub {
             const data = Buffer.from([0x81, portObj.value, 0x11, 0x51, 0x00, brightness]);
             this._writeMessage(Consts.BLECharacteristics.LPF2_ALL, data);
             if (time) {
-                setTimeout(() => {
+                const timeout = setTimeout(() => {
                     const data = Buffer.from([0x81, portObj.value, 0x11, 0x51, 0x00, 0x00]);
                     this._writeMessage(Consts.BLECharacteristics.LPF2_ALL, data);
                     return resolve();
                 }, time);
+                portObj.setEventTimer(timeout);
             } else {
                 return resolve();
             }
diff --git a/hub.ts b/hub.ts
index 23cd983..c4160bb 100644
--- a/hub.ts
+++ b/hub.ts
@@ -304,7 +304,7 @@ export class Hub extends EventEmitter {
     }
 
 
-    protected _calculateRamp (fromSpeed: number, toSpeed: number, time: number) {
+    protected _calculateRamp (fromSpeed: number, toSpeed: number, time: number, port: Port) {
         const emitter = new EventEmitter();
         const steps = Math.abs(toSpeed - fromSpeed);
         let delay = time / steps;
@@ -330,6 +330,7 @@ export class Hub extends EventEmitter {
                 emitter.emit("finished");
             }
         }, delay);
+        port.setEventTimer(interval);
         return emitter;
 }
 
diff --git a/port.ts b/port.ts
index 2f3ae31..508f703 100644
--- a/port.ts
+++ b/port.ts
@@ -6,19 +6,28 @@ export class Port {
 
     public id: string;
     public value: number;
-    public connected: boolean;
     public type: Consts.Devices;
-    public busy: boolean;
-    public finished: (() => void) | null;
+    public connected: boolean = false;
+    public busy: boolean = false;
+    public finished: (() => void) | null = null;
 
+    private _eventTimer: NodeJS.Timer | null = null;
 
     constructor (id: string, value: number) {
         this.id = id;
         this.value = value;
-        this.connected = false;
-        this.busy = false;
-        this.finished = null;
         this.type = Consts.Devices.UNKNOWN;
     }
 
+    public cancelEventTimer () {
+        if (this._eventTimer) {
+            clearTimeout(this._eventTimer);
+            this._eventTimer = null;
+        }
+    }
+
+    public setEventTimer (timer: NodeJS.Timer) {
+        this._eventTimer = timer;
+    }
+
 }
diff --git a/puphub.ts b/puphub.ts
index 2f29a66..699f8d0 100644
--- a/puphub.ts
+++ b/puphub.ts
@@ -74,6 +74,7 @@ export class PUPHub extends LPF2Hub {
                 throw new Error(`Port ${portObj.id} requires both motors be of the same type`);
             }
         }
+        portObj.cancelEventTimer();
         return new Promise((resolve, reject) => {
             if (time) {
                 let data = null;
@@ -84,7 +85,7 @@ export class PUPHub extends LPF2Hub {
                     data = Buffer.from([0x81, portObj.value, 0x11, 0x60, 0x00, this._mapSpeed(speed), 0x00, 0x00]);
                 }
                 this._writeMessage(Consts.BLECharacteristics.LPF2_ALL, data);
-                setTimeout(() => {
+                const timeout = setTimeout(() => {
                     let data = null;
                     if (portObj.id === "AB") {
                         data = Buffer.from([0x81, portObj.value, 0x11, 0x02, 0x00, 0x00]);
@@ -94,6 +95,7 @@ export class PUPHub extends LPF2Hub {
                     this._writeMessage(Consts.BLECharacteristics.LPF2_ALL, data);
                     return resolve();
                 }, time);
+                portObj.setEventTimer(timeout);
             } else {
                 let data = null;
                 if (portObj.id === "AB") {
@@ -119,8 +121,10 @@ export class PUPHub extends LPF2Hub {
      * @returns {Promise} Resolved upon successful completion of command.
      */
     public rampMotorSpeed (port: string, fromSpeed: number, toSpeed: number, time: number) {
+        const portObj = this._portLookup(port);
+        portObj.cancelEventTimer();
         return new Promise((resolve, reject) => {
-            this._calculateRamp(fromSpeed, toSpeed, time)
+            this._calculateRamp(fromSpeed, toSpeed, time, portObj)
             .on("changeSpeed", (speed) => {
                 this.setMotorSpeed(port, speed);
             })
@@ -139,15 +143,17 @@ export class PUPHub extends LPF2Hub {
      */
     public setLightBrightness (port: string, brightness: number, time?: number) {
         const portObj = this._portLookup(port);
+        portObj.cancelEventTimer();
         return new Promise((resolve, reject) => {
             const data = Buffer.from([0x81, portObj.value, 0x11, 0x51, 0x00, brightness]);
             this._writeMessage(Consts.BLECharacteristics.LPF2_ALL, data);
             if (time) {
-                setTimeout(() => {
+                const timeout = setTimeout(() => {
                     const data = Buffer.from([0x81, portObj.value, 0x11, 0x51, 0x00, 0x00]);
                     this._writeMessage(Consts.BLECharacteristics.LPF2_ALL, data);
                     return resolve();
                 }, time);
+                portObj.setEventTimer(timeout);
             } else {
                 return resolve();
             }
diff --git a/wedo2smarthub.ts b/wedo2smarthub.ts
index b50a38d..6494871 100644
--- a/wedo2smarthub.ts
+++ b/wedo2smarthub.ts
@@ -125,13 +125,16 @@ export class WeDo2SmartHub extends Hub {
      * @returns {Promise} Resolved upon successful completion of command. If time is specified, this is once the motor is finished.
      */
     public setMotorSpeed (port: string, speed: number, time?: number) {
+        const portObj = this._portLookup(port);
+        portObj.cancelEventTimer();
         return new Promise((resolve, reject) => {
-            this._writeMessage(Consts.BLECharacteristics.WEDO2_MOTOR_VALUE_WRITE, Buffer.from([this._portLookup(port).value, 0x01, 0x02, this._mapSpeed(speed)]));
+            this._writeMessage(Consts.BLECharacteristics.WEDO2_MOTOR_VALUE_WRITE, Buffer.from([portObj.value, 0x01, 0x02, this._mapSpeed(speed)]));
             if (time) {
-                setTimeout(() => {
-                    this._writeMessage(Consts.BLECharacteristics.WEDO2_MOTOR_VALUE_WRITE, Buffer.from([this._portLookup(port).value, 0x01, 0x02, 0x00]));
+                const timeout = setTimeout(() => {
+                    this._writeMessage(Consts.BLECharacteristics.WEDO2_MOTOR_VALUE_WRITE, Buffer.from([portObj.value, 0x01, 0x02, 0x00]));
                     return resolve();
                 }, time);
+                portObj.setEventTimer(timeout);
             } else {
                 return resolve();
             }
@@ -149,8 +152,10 @@ export class WeDo2SmartHub extends Hub {
      * @returns {Promise} Resolved upon successful completion of command.
      */
     public rampMotorSpeed (port: string, fromSpeed: number, toSpeed: number, time: number) {
+        const portObj = this._portLookup(port);
+        portObj.cancelEventTimer();
         return new Promise((resolve, reject) => {
-            this._calculateRamp(fromSpeed, toSpeed, time)
+            this._calculateRamp(fromSpeed, toSpeed, time, portObj)
             .on("changeSpeed", (speed) => {
                 this.setMotorSpeed(port, speed);
             })
@@ -191,11 +196,12 @@ export class WeDo2SmartHub extends Hub {
             const data = Buffer.from([portObj.value, 0x01, 0x02, brightness]);
             this._writeMessage(Consts.BLECharacteristics.WEDO2_MOTOR_VALUE_WRITE, data);
             if (time) {
-                setTimeout(() => {
+                const timeout = setTimeout(() => {
                     const data = Buffer.from([portObj.value, 0x01, 0x02, 0x00]);
                     this._writeMessage(Consts.BLECharacteristics.WEDO2_MOTOR_VALUE_WRITE, data);
                     return resolve();
                 }, time);
+                portObj.setEventTimer(timeout);
             } else {
                 return resolve();
             }