I have a 2004 yfz 450 quad that while riding my thumb starts to cramp becouse of the tension of the thumb throttle. I have herd that you can change the carb spring to one off a honda trx450 that will take care of this. Is this carrect? or does anyone have a part # or a source to where i can order one?

ebay carb spring
this is what I put in mine and I haven't had any more problems with my thumb cramping up since I put it almost two years ago.

The ebay carb spring is what you want as far as the spring is concerned.
It's the Honda thumb throttle itself (not the Honda spring) that people like more than the YFZ's because it is has better ergonomics.

Thanks for the info. that is just what i needed.

u can buy it or u can just cut your spring down like 3 rows i cut mine and works great