I just looked on the eibach site and it said the stock rear rate for 2003 XR400 was 9.5. I always thought stock honda spring was 9.9 kg/mm. I'm not sure if the eibach site is listing rates in kg/mm or nm. I just got a 9.5 assuming it would be a little lighter than stock and I could get my sag #'s correct. If I just got the same as stock I'll have to send back, I'm not even going to try and put it on. I'm hoping that the site is wrong as it also lists front stock rates at .38 instead of .40. Anybody have any insight on this? Anyone running eibach rear spring? BTW I'm 165lbs w/o gear.