The latter charge relates to one of Te Rupe's passengers who suffered facial abrasions and needed hospital treatment.
In her victim impact statement, the deceased's mother Sheryl Wilson said: "Our son was no saint but he didn't deserve to die at the hands of someone who shouldn't have even been on the road."
She said having to identify her son's broken body and visiting the crash site haunted her and she cannot believe this happened at all.
Losing her son, who absolutely "loved life" and was an innocent person out enjoying riding his bike, had left a "huge bent in her heart" that can never be healed.
"As my husband says, it felt like his heart was wrenched from his chest when we learned of Grant's death," she said.
Sheila said their lives and the lives of Grant's friends and workmates would never be the same, and her son's mates had taken his death very hard.
Mrs Wilson said the "hardest thing as parents" was having to tell the rest of the family, go through her son's possessions and settle his affairs.
"We have suffered indescribable loss and have to live with that every day, and there is no escape from those feelings of loss," she said.
Haley Wilson, who lives in Australia, said one of the hardest things for her was not being able to attend her brother's funeral due to the Covid-19 pandemic.
"I will always feel deeply saddened that I wasn't there to say goodbye in person."
Haley said even today the sound of ambulances and sirens were vivid reminders of her brother's horrific death and she often cried herself to sleep and dreamt of him.
"Grant was someone who would give anyone the shirt off his back and he was the first to help anyone," she said.
She said Te Rupe's irresponsible actions had "changed their lives forever".
The court heard that earlier on the day of the crash Te Rupe attended his father's unveiling memorial service at Waiotahi Valley Rd near Whakatāne.
Te Rupe drank alcohol and consumed cannabis throughout the day, and after the function, he and his group drove towards Murupara.
Initially, someone else was driving but Te Rupe insisted on taking the wheel - despite being a disqualified driver - after telling the driver he "drove like a slug".
Due to Te Rupe's erratic driving, the left rear tyre burst and a spare tyre was fitted. Despite efforts from his passengers, he refused to allow anyone else to drive his vehicle.
Te Rupe drove at speed, often cutting corners, and at the Pekatahi Bridge intersection, he pushed in front of a line of traffic and failed to stop for a red light.
He was forced to reverse the length of the bridge in order to give way to a row of traffic.
Te Rupe continued to speed along White Pine Bush Rd and as he travelled around a bend his vehicle crossed the centre line into the path of Wilson's motorcycle.
Wilson was killed instantly.
While on remand in Waikeria Prison, Te Rupe made several phones calls urging the receivers to ensure they and their associates kept "their mouths shut" about the crash.
He also attempted to get an associate to lie in relation to his bail application.
Justice Grant Powell sentenced Te Rupe to seven years and four months' prison after taking into account his guilty pleas, and offer to participate in a restorative justice meeting with the victim's family.
Wilson's family declined that offer, the court heard.
Justice Powell said despite Te Rupe insisting this was an accident, the manslaughter charge stemmed from his "prolonged and persistent excessive speed and clearly aggressive driving".
He said Te Rupe being disqualified from driving, consuming alcohol and drugs and attempting to interfere in the course of justice were aggravating features.
The judge said Te Rupe's use of his gang connections to try to intimidate and physically threaten passengers and a Crown witness was a "very serious" matter.
"Make no mistake Mr Te Rupe this was no accident," he said.
Justice Powell also rejected Te Rupe's legal counsel Roger Gowing argument that he should give Te Rupe a discount for his stated intent to rehabilitate himself.
"It would be so wrong and indeed abhorrent to accept that in the absence of any real commitment to putting your gang lifestyle behind you," he said