Top five best bikes 

The CRF450R is the best bike out on the market. It's the lightest the fastest and the smoothest. It weighs 210 with no gas. It has the new RG3 shocks and a lot of new motor work.
The YZF 450 is second for its hard hitting power band and redone forks. It also has titanium bolts pegs and frame for strength and weight.   
KX™450F Kawasaki's KX450F is third in the line-up. Its suspension isn't its strength but it has power from top to bottom and excel wheels make up for its suspension. 
The KTM 450 SX
Suzuki RM-z450 RM-Z 450

Cody H