If i understand the links a 60Hz korean made AC motor will run 20% slower using 50Hz Malaysian electricity.. This might cause a problem with your juicing speed controls.

A 220V Korean motor should be able to handle additional 20V (9%). Our Malaysian 240V electricity should not cause a safety issue but it would make it run hotter then 220V.

Running hotter to damage the motor would mean hot enough to melt the stator winding insulation. This would mean temperatures well above 200 plus degrees Celsius as the insulation is basically just plastic polymer or pvc.
You will be able to smell that burning plastic aroma of electrical fires.

Here's a little test to see if your juicer is safe, switch on your juicer and turn it to its maximum setting. Let it run for about 15 minutes or the longest time you would reasonably use it. Now put your hand on the base where the motor is. If it is feels unreasonably hot then stop using it. If it is just warm then it should be ok to use.