Today I will show you guys how to drain, flush and refill the radiator on a Yamaha YZ450F (2008).
All you need is an 8mm socket, new radiator coolant, and a bucket.
The 2008 model year is generation 4 so it is the exact same for 2006 - 2009 models. Probably very similar for newer / older models too and honestly also probably similar for most MX racing type dirt bikes.
Hope you enjoy and learned!