Super clean!

TPR

 

Depends on rider

 

An 87 cr 500.

 

The YZ is a great powerhouse bike, but it was never really competitive with the CR or KX500 (air cooled, older chassis tech, etc). It was known for excellent low end torque and a stout midrange, but way less top end than the competition and it was behind in basically every category, not to say that it wasn't capable. Which is just fine for what I want, because the CR and KX would be too scary to ride and the YZ would be a little friendlier for recreational riders. I like the fact that it's air cooled actually, as it has more than plenty HP/TQ already and it's very simple. Unfortunatley, I have heard about lots of reliability problems too, but man I bet it's a blast if you have it well tuned and maintained!

The CR500R is the monster of monsters!

 

In 92 the yz490 motor was brought back from the dead, and put in an all new, better handling chassis. The wr500 was born. Yz490 wasn't as good out the box as a cr500 or kx500, but savvy 490 tuners tossed the 40mm mikuni, in favor of a 38mm, reshaped the head {squish area}, and dialed in less timing advance. These were the same things yamaha did when they made the wr500. Anyway the cr500 and kx500 were alittle better than the yz490 and wr500.