[DanQ]

What measurements are you coming up with, and what did you adjust?

The bike comes with .92 kg/mm front springs and a 10.0kg/mm rear. A 65 kg rider would need around a .932 kg/mm (tiny difference) and 11.63kg/mm rear (still realistically not a huge difference).

You should be able to hit or come reasonably close to desired sag settings.

 

[DanQ]

Op, not sure how you are measuring to get those figures. Static or rider sag?
Racetech calculator recommends stock spring rates for your weight.
http://racetech.com/ProductSearch/2/Yamaha/YZF-R6/2008-12
Static sag ~20mm front ~10mm rear (bike weight without rider from topped out measurement)
Rider sag ~35mm front ~30mm rear (bike and rider weight combined from topped out measurement)

Dan, where are you getting those figures from as I am 220 pounds and currently on a 10.7kg rear. I'm looking to go to a 11.2kg to achieve 8-10mm static sag at 25mm rider sag. 11.63kg for 65kg seems really stiff?

I used the calculator on Race Tech's website.

 

[DanQ]

Op, not sure how you are measuring to get those figures. Static or rider sag?
Racetech calculator recommends stock spring rates for your weight.
http://racetech.com/ProductSearch/2/Yamaha/YZF-R6/2008-12
Static sag ~20mm front ~10mm rear (bike weight without rider from topped out measurement)
Rider sag ~35mm front ~30mm rear (bike and rider weight combined from topped out measurement)

Dan, where are you getting those figures from as I am 220 pounds and currently on a 10.7kg rear. I'm looking to go to a 11.2kg to achieve 8-10mm static sag at 25mm rider sag. 11.63kg for 65kg seems really stiff?

I used the calculator on Race Tech's website.

And input the wrong machine :comp

Came up with stock of .90 kg/mm and 9.8 kg/mm, with a 65kg rider needing .858 kg/mm front and 9.886 kg/mm rear. So his springs should be dead on unless I input it incorrectly again. I do apologize for the confusion.

 

[DanQ]

For race bikes, rear sag is typically 25 to 30mm. Street riders usually use 30 to 35mm. Bikes set up for the track are compromise when ridden on the street. The firmer settings commonly used on the track are generally not recommended (or desirable) for the street.
Racers often use less sag to keep the bike clearance, and since race bikes work greater than we see on the street, they require a stiffer setup.
It's important to stress that there is no magic number. If you like the feel of the bike with less or more sag than these guidelines, great. Your personal sag and front-to-rear sag bias will depend on chassis geometry, track or road conditions, tire selection and rider weight and riding preference.

Well stated :bow