i don't understand 160-165 main jets?

[paparattler]

i'm running 130 main jets,yellow carbsprings and my secondary spring twisted to 100 degrees.everything else is stock.my son destroyed the old hillclimb at allen,i was to chicken.my question why are some of you running 160-165 jets isn't that way to rich or does this machine need that much fuel.next week we are going to revy for 5 days.we usually ride at 4000-8000 feet.thanks

 

[Toolman]

The extra large mainjet is for K&N filters, not the stock airbox.

 

[paparattler]

thanks toolman for your clarification.