Stock rear spring rate Q's / 2003 XR400

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.

Me too, it was the eibach site that threw me for a loop. Couldnt find it in the manual either. I'll just put it on and see what happens I guess. Both Racetech and the tech info on 4strokes.com both say 9.8, 2 out of 3 aint bad I guess!:ride:

Thanks man! :cheers:

.40kg/mm's on the front come stock and I'm not sure about the rear but at 200lb.s the stock spring is just right for me. The fronts on my bike got changed to .46kg/mm's and that's ideal as well. It's what Race Tech used to recommend but now they have changed. Call someplace like XR's Only or Precision Concepts to get a good bit of info. Both of them have lots of experience with XR's.

difference from 9.5 to 9.9 is insignificant. From 10.0-11.0 is only 20lbs difference (rider weight)

I run an Eibach 9.0 kg/mm, 185lbs w/o gear and it's perfect for me. I rarely bottom out with the comp clicker wide opened, however i'm not very hard on my bike, no big jumps but fast trail riding.

Spring calculator said 9.1kg for my weight, "use closest available". Closest was a 9.5, next one down was 8.5 but I couldn't find a 9.0 anywhere.

Anywho,,, it's on now. Took 2 hrs, 1 break for a samich and a quick shot of crown to keep my spirits up. I even adjusted the spray nozzle on my mikuni pumper so it hits the needle while I had her skirt up. Everything is torqued back down and together but I have not set sag yet. Just made sure all was buttoned up good and called it good for the night. 1st impression is it "feels" a little softer but the #'s wont lie, I'll find out for sure tomorrow. I put 6mm pre load on it as a start, free sag is about 1.75" now :cheers: so I'll add more to it tomorrow and get my brother to come over and help me measure race sag.

http://www.precisionconceptsracing.com was the only place to have one when I was searching that shock spring.

Cool, thanks! If the 9.5 doesnt work out I'll get a 9 or go straight to 8.5 depending on what I see tomorrow. I think I'll be close based on the #'s I had with the stocker. I'm not sure how much difference it actually makes but I run a 110 link chain so I can adjust the wheel back further. Did this for a little longer wheelbase and was hoping I would put a little more leverage on the stock spring.

Sag is set. Worked out well. :cheers:

Cut up an old tape measurer for a home brew sag scale, that worked great as well. Ended up with 35mm free sag and 105mm race sag. Thats right where I was aiming based on what Dwight Rudder recommended.

Made sure I had all my gear and back pack on, plus the tool pack on the bike loaded with what I always carry. Basically, everything I have with me when I leave the truck from the trail head.

Next up is an oil change and shim mod on the forks. I'll let Enduro Engineering take care of the shock service next time I head towards Lansing. $50 -60 for a shock oil change is worth it to me. Maybe I'll try it myself next time.

Ended up with 35mm free sag and 105mm race sag.

I think your free sag # is a bit high, and maybe the spring is still too stiff for you, but if it feels good... I'm happy for you!

I think your free sag # is a bit high, and maybe the spring is still too stiff for you, but if it feels good... I'm happy for you!

Thanks! Just went with the #'s Dwight recommended. He does mention he prefers a little stiffer spring with more free sag than usual. I figure copying his set up would be a good start. Every post I read where people did, gave great feedback on how well it worked. Sheet with the spring said 25 max and 100 max. I'll try it out this weekend at Cedar Creek and see if it handles the sandy stuff better. I just love tinkering with the stuff, this set up may work better but if it doesnt, oh well. I'll just try again with something else. It's all good fun to me. :cheers:

Damn I am big guy. I weigh 230 with out gear and easy 250 with gear, tools, water and pack. I am running a 12.5 in the rear.

Are you supposed to have the bike set up for all your gear on or have it set Up with no gear on? To me it seems like gear on is how it should be done. Is this correct?

Yes, all gear on. I even put my back pack on with the stuff I carry with me, tools extra jacket etc. and some water in the hydro bladder. I'm about 165 in the buff and closer to 180-185 all geared up. Now if I can find some platform boots I might be able to touch the ground with both feet on the 'ole girl! :cheers:

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