In the first crash on the Thames Coast Rd, between Russek Rd and Manaia Rd, a truck and a motorcycle collided about 8.50am on October 7.
Then yesterday afternoon a man was seriously injured after his motorbike and a truck collided on SH27 about 1pm. A motorcyclist in Hamilton died after his bike and a car collided on SH1 at the intersection with Johnsview Terrace.
The cases were all now in the hands of the Coroner, but Penno said "some" of the crashes were the result of motorcyclists making mistakes.
"Whilst we can't talk about the causation because it's too early at this stage, motorcycle riders are vulnerable and they need to take that responsibility themselves.
"A lot of police, including myself, ride motorbikes daily so we understand the risks, we understand the danger.
"Prima facie there have been mistakes made in some of the crashes by the motorcyclists. So your obligation as a motorbike rider is to be licensed to ride your machine, wear good protective clothing and be compliant with the road rules.
"This is not the police trotting out road safety lines this is what will keep you alive on the roads."
He said some riders needed to remember that as they got older their motorcycle skills could get rusty.
"You've got to understand the inverse relationship between getting older and your skill level riding a motorcycle. We were all awesome riders 40 years ago. I used to ride a motorbike daily but I accept that I'm not as sharp as I used to be."
He urged all riders to ensure their bikes were compliant and they were alert at all times.
"Before you get on the bike, make sure you're licensed, make sure your bike is good and your gear's good."
The country was soon going into the motorcycle season and a rider's obligation was not only to themselves and other road users, but also for the sake of their family and loved ones.
