Yamiha97, yeah a race ready dirtbike is quite different from the more lazy drz. What its all about is how used you are to the bike. A few years ago a had a yamaha wr 125, i could even pull that turtle up in 5-6 gear at 100 km/h (with my life at stake haha) but then i got a yz 125. The yz had over two times as many hp but i could not wheelie that bike as good as my WR 125 with just 13-15 hp. Its all about what you are used to and how good you are.
If you struggle with wheelies on the drz (and not on a 450 dirtbike) you should just start to practice more often on the drz and you will get better fast since you allready know the basic's