Bird passed away two weeks ago aged 56 after a short illness, sending shockwaves throughout the sport in the UK and further afield.
His PBM BeerMonster Ducati team currently leads the standings going into the final three rounds, with England’s Tommy Bridewell holding a narrow advantage of 14.5 points over Carrickfergus man Irwin, who is bidding to become Northern Ireland’s first BSB champion.
Ahead of opening practice on Friday, Irwin revealed he will wear a special edition Shoei helmet as a tribute to Bird, who oversaw a record eight BSB titles for his Lake District-based team.
Irwin said: “Within the team we knew Paul wasn’t well and we’d been aware since after Brands Hatch, which was the last race he attended before Thruxton or Cadwell.
“You can look at it with great sadness and when I found out it was a huge shock, despite knowing he hadn’t been well. We always hoped or believed there could be a different outcome.
“Once you get over that initial shock, we are in the middle of what has been a very successful season to date, for myself – including at the North West 200 – and in BSB too, and for the team in general.
“We must and we will continue to focus on the same way we have all year and I think there should never be any extra motivation to win British Superbike races or the championship, but it will certainly make what may come in the next few weeks all the more emotional,” added the 33-year-old, who was last year’s championship runner-up behind Bradley Ray.
“I think right now, it’s about maintaining focus and the team is obviously racing on in Paul’s memory. But I think at the end of the year when we really sit down and reflect on the fact that the ‘Birdman’ is gone, we can get a little bit more upset and emotional about it.
“I’ll be forever grateful for the opportunities I had [with PBM]. A lot of my ‘firsts’ came through PBM; my first North West win, my first BSB podium and BSB win, and wouldn’t it be all the sweeter to also win my first BSB title.
“For sure, that will be another thing to be grateful for to Paul and to his team.”
Elaborating on the tribute helmet he will don in Bird’s memory at Oulton, Irwin said it was his way of honouring his former team boss.
“I am paying tribute this weekend with a special edition helmet, which will touch on all the titles and race wins in each discipline that PBM achieved from the beginning, right up to Paul’s passing; the Sunflower Trophy is covered on it, Scarborough – everything,” he revealed.
“That’s a way that I will pay tribute and whilst paying tribute, I will continue to do my job, which is the best thing for me to do and continue this great journey that I am on for Paul.
“I’ll wear it all weekend to honour him. Someone asked if I would only wear it during the races in case I crashed, but I don’t think like that and it wasn’t in my head to keep it just for a race day.”
Irwin won twice last time out at Cadwell Park before Bridewell responded with a hard-fought victory in the final race.
Saturday’s Sprint race is at 4.15pm with Sunday’s BSB races scheduled for 1:15pm and 4:15pm.