Those who have undergone a Pre Learner, Pre Provisional or Roadskills Course will probably have some memory of the trainer talking about crash avoidance space.
Hopefully he/she would have talked about a safe following distance.
The closest a motorist (motorcycle or other vehicle) should be to a vehicle in front is 3 seconds. i.e as the vehicle in front passes a fixed point, count one thousand, one, one thousand two, one thousand three. You should be passing that point by then.
This gives adequate time for you to see what is happening up front, decide what to do and put it into action, allowing you and your bike to come to a safe stop if necessary in ideal conditions, if the road is wet or weather, traffic is not good add more time in.
The only time you should be closer to the vehicle in front of you is just prior to overtaking.
Yes dipsticks will steal your space, do not worry about it, regain your space and continue your journey.
Remember safe riding doesn’t happen by accident!!