Hey mcromo44 great to hear from you
Yes sir still have my 919. I picked up the tuono for a song.
Any way to your point yes, the fors are vastly more compliant, however if I am not super diligent she dives hard and has bottomed out several times. thoughts?
First off, let’s all keep in mind I have zero first hand experience with a Tuono, R model assumed, so all I can do is research a bit and go from there.
I used the Racetech link that K1w1Boy kindly posted.
But I could not find your bike listed, so no luck there.
I found a bunch of info on the Sport Rider website, including a road test article.
I looked at their measured wet weights info.
Based on that alone, tells me your Tuono is in the same weight league as our 919s.
If one assumes a nominal 50 /50 fore and aft axle weight distribution, it becomes even more comparable to our 919s which in the case of my bike as set up, is 49% Front / 51 % Rear. (this is recent info from late last year, I had the bike weighed up by a local race whiz, so my historic comments about 919s being rear biased have been shattered as being proved wrong)
Short story, I figured that based on your riding criteria, way more so than your weight, that 0.95s would likely be the lighter side of the ideal range.
Then I fished about and found a website in Europe that said the stock front springs are 0.92 kg/mm and their purely rider weight based selector said the “ideal” rate would be 0.98.
I assumed their selector is more useage based than rider weight, so my above suggestion of 0.95 still sounds very much in the zone.
I suggest starting with 10 mm of installed preload for 0.95s. (If you ever tried 1.0s at the track you might want to try 5 mm.) (Keep in mind that I have zero knowledge as to what the top out characteristics are for your forks.)
This morning, I thought about Traxxion Dynamics, whose website I have not visited in years. Guess what I found there ? A no selector method other than the bike, and one kit for the bike using 0.95s !
If you were doing lots of track days at pace, and didn’t care about road ride, I’d say start at 0.975 and maybe also try 1.0s, but I’m thinking you can’t go wrong with 0.95s for the riding you have described.
My assumption is that your bottom out dive is front brake induced, and nothing else but. Springing will be part of that, but not near all of it.
Are you holding yourself up with the bars against the braking force? If so, that’s a big dive component, especially if your elbows are rigid (also a negative grip factor).
Are you building brake pressure too quickly? If so, that’s another big dive component. (look for ideal brake pressure curve plots as added insight on this point)
Low Speed Compression is an element.
Preload is an element. (both installed and externally adjusted setting)
Oil is an element.
Oil level is an element.
Unless you know what oil you have, change it to what Ohlins recommends.
I suggest going to a 125 mm oil level and be done with it.
Back to Sport Rider, I found their “all models tested” settings info.
Here’s what they say for your bike:
• 4 lines on the preload adjuster showing.
• 0.75 turns out from full hard of the rebound adjuster
• 1.50 turns out from full hard of the compression adjuster
• Fork tube 4 mm showing above the top of the upper triple clamp.
Before you do anything, try their settings first so you know how those changes compare to what you presently have as settings.
Hopefully this helps you along at least some.
As for your bike, the Tuono that is, my comment is “want want / covet covet” !