Spring rate specification

[Doxgon Racing]

Does anyone know the spring rate for the stock rear shock spring? I have spent the last hour reading through the service manual and google-ing Buell specs, to no avail. I am thinking about trying to put a Sportster shock on my Redneck Engineering-framed Blast, but I'm afraid that the spring rate will be too stiff, effectively making it a rigid (not acceptable). Any help would be greatly appreciated.
Thanks, Doc

[ezblast]

800 to 900
EZ

[Doxgon Racing]

Thanks

[Doxgon Racing]

For what its worth, Trackside Suspension and Engineering (TSE) scaled my spring, and determined the rate at 960 lbs/in at one inch of preload. The catalog I looked at referencing Ultima shocks for Harleys said that each inch of spring compression doubles the rate, so it is possible that the first inch of spring rate could be as low as 480.