"It is so hard. I do not think riders realise just how tough it will be. If it is a typically hot Hawke's Bay day then it will be absolutely brutal. It is harder than Christchurch."
Bevin believes it will prove a war of attrition, with the course not favouring any particular type of rider.
"Being a 60kg climber is not going to help much over that climb. There's just not going to be any easy way to get around. You will have to hang tough for as long as you can and hope to have some legs left for the final lap."
His new Cannondale Pro Cycling team have given him the green light to prepare well for the nationals, as a preview for the Tour Down Under in South Australia the following week.
"They want me fit and ready to go for the Tour Down Under and that means I need to be in reasonable shape for the nationals.
"I love the nationals and always will. And I am rapt with the course they have designed for this event. It is going to be epic for the riders and the fans."
He is equally pleased with the layout for the time trial which starts and finishes at the Church Road Winery.
"It has got a good mix of technical with some hills, which is a pleasant change. They have done a fantastic job with this course and I am looking to do well. The time trial is something I've been working on with my coach."
The nationals begin with the time trials at Church Road Winery on Thursday. The elite women's road race will be run over 117km, including 4.5 loops of the inner-city course on Saturday and the elite and under-23 men's race on Sunday will cover 180km, with 7.5 laps in the Napier CBD.