"Having raced Yamaha in Australia and in Finland and Mexico, I already had a great rapport with the Yamaha guys. So, when the opportunity came up, I simply could not turn it down.
"It feels like I'm rejuvenated, switching to a different brand.
"I feel a new sense of excitement and now, more than ever, I have gotten that eagerness to get out there and ride.
"I will do some modifications to the Yamaha WR450F to suit my riding style, but, from my initial riding, it is a very good base to work from. Plus, I rode the new WR at the 24-Hour Australian Enduro, so it's not like it is totally new to me."
Yamaha New Zealand's Peter Payne said he, too, looked forward to the strengthened association.
"He's won on a Yamaha at the International Six Days Enduro and twice won on a Yamaha at the 24-hour race in Australia, so he's already tasted great success with our bikes."
Power and Reeves look strong favourites to win tomorrow.