?
Everthing I've researched they are great upgrades but what if I'm just running stock tires?
Still worth it or is the factory tuning right on?

 

Even with a stock set-up clutching can make a big difference. It all depends on what you want out of the machine. More low end? more top end? A more positive engagement, etc. Some may argue, but IMO. for a stock set-up there's still room for improvement.

 

as mentioned it all depends on what your looking to gain or get out of it. you may be able to just put a spring in to gainm what you want, but there again it depends on what you want.