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Discussion Starter #1 (Edited)
97 Monster 900 Showa 41mm non-adjustable forks. Both of my manuals show original amount of oil (457cc) and a depth of 79.5mm. Then the note says the amount was changed from 457cc to 487cc but does not give revised oil depth.
Anybody care to share the revised depth??. Quick math tells me that if the internal volume of the fork is a constant as the oil height decreases, then the new depth would be ~75mm. But I think I'm wrong. I'm sittin here with my laptop on my bearing press and I smell like kerosene. Please Help
 

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I've never heard of a fork oil level of less than 100mm from top, springs out, fully compressed. Usually it's 110 - 120mm.
 

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Discussion Starter #3
Thanks Chuckracer. 110 is the level I had in my head when I started this. Don't know where it came from though. My mistake is reading the manual. It shows all 97 m900 (non adjustable) as showa ~80mm (before confusing revision) and ~90mm for non adjustable marzocchi. All the ADJUSTABLE monsters show ~110mm. Anyone else wanna chime in before I fill these babies up?? I'm still not sure.
 

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Discussion Starter #4
Thank you for the help. Since the forks had been completely disassembled and were dry I decided to go with the volume measurement. Haynes and Ducati gave the revised # of 487cc. After priming the damper rod then collapsing the damper and the fork the 487cc filled the fork up to about 18mm from the top of the tube. I was hoping the number would be closer to the expected 70mm to 110mm. I do wonder if with a little time the air gap between the od of the inner and and the id of the outer leg will fill with oil, thus lowering the height of the oil to be more in line with what I was expecting. Any more thoughts on this situation will certainly be appreciated.
 

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Discussion Starter #6
Sorry, I misspoke. 18mm from top was after spring and spacer. Before them the oil to top of tube was approx 37mm. Still not what I was expecting. I did notice in a video that you (Chuckracer) linked for me that a step was specifically added to fill the air gap I mentioned in my previous post. With that in mind, hopefully I have the correct amount of oil, it just needs to settle in a bit. Forks are back together now. Each individual fork would compress to about 2.5" to 3" from end of travel with my 170 pounds pressing down. Then once they were installed if I straddled the bike and bounced the front by pressing all my weight down on the handlebars there was about 3" of travel left at max compression. I'll ride in the morning and see what happens.
 
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