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Just rebuilt my stock Showa forks. The stock springs were too soft for my weight (260lbs) in full gear. I upgraded to a set of Traxxion Dynamics 1.05kg/mm spring kit, and used Maxima 10wt fork oil @ 125mm air gap. Now just need to get it tuned right.
Looking to see if there are any others running a similar setup, and wondering if I should have stayed with the 7wt oil?
 

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Ducati configures the dampers such that the recommended click settings for a 75 kg rider falls in the middle between maximum and minimum damping. The only reason to change from the recommended viscosity is if you run out of high (or low) damper settings and you need even more (or less) damping than the maximum (minimum) that the nominal 7.5 weight provides.

You can compensate for using a higher or lower viscosity oil by reducing or increasing your adjustable low speed damper settings, but the fork's high speed damping is provided by the internal shim stack – so high speed damping will be reduced by using a lower viscosity fork oil, for example.

So, pay attention to damping softness or harshness when encountering potholes and poor road surfaces that cause the shim stack to control damping. Too much high speed damping – reduce fluid viscosity.

Shell Advance Fork 7.5 (22) and Showa Suspension Fluid SS-08 (36.5) have quite different viscosities. Shell Advance Fork 7.5 low viscosity makes no sense to me. I can only surmise that Ducati's racing sponsorship by Shell has something to do with it. Previous to the Shell sponsorship, Showa Suspension Fluid SS-08 was recommended by Ducati for use in all Showa forks.

Note that Ducati Manuals also list Shell Donax TA as an alternative to Shell Advance Fork 7.5, yet they have quite different viscosities. I would use Shell Donax TA because its properties are closer to Showa SS-08. Maxima 10 wt is a better choice than 7 wt, particularly when used to control quicker rebound needed for use with stiffer springs

Showa has extensively tested their fork seals with the hydraulic fluid they have chosen to be specified in the Ducati Manuals. This is not to say that fork oil from another manufacturer will result in damage to the fork seals, they simply haven’t been tested by the fork manufacturers for long term compatibility with their particular seal material. So I use SS-08.

Note that the air spring that changes with fork oil fill level is unaffected by fluid viscosity.
 

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Shazaam I always love reading your informative replies!

I ignore the 'weight' numbers and focus on vicosity. For the last few years I have used Ohlins 01313-01, which is/was rated 23cST @ 40C. However, I cannot find that any longer and will be switching to another brand during the upcoming off-season. I was quite happy with the stock fluid properties (and the Ohlins as well), so I have tried to match the cST and index numbers as closely as possible. I'm planning to try Golden Spectro 7.5W which matches Shell Advance fairly close.

Shazam, which spec number (or combination) is the most important in your opinion? And, should Golden Spectro not be considered over SS-08?

Here are the other fluids I considered, but after reading your reply, I might 'pump up' the viscosity a little more...

Bigtex, I would love to hear any feedback you have on the differences between the stock springs and the new TD kit...
 

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This links has nearly all the viscosity result:
Fork oil weights

It seems Shell Advance Shell Fork 10 has the closest property as Showa SS8.
BTW, do we actually need to care about viscosity at 100 deg C??

Showa Suspension Fluid SS8 (10wt)
Nominal Weight: 10
Reported cSt @40C (centiStokes): 36.47
Reported cSt @100C (centiStokes): 7.24
Reported Viscosity Index (VI): 200
Recaclulated Viscosity Index (VI): 167
Viscosity/ Temperature Coefficient (VTC): 0.8
VT ([email protected]/[email protected]): 5.04

Shell Advance Fork (10wt)
Nominal Weight: 10
Reported cSt @40C (centiStokes): 38.97
Reported cSt @100C (centiStokes): 7.44
Reported Viscosity Index (VI): 161
Recaclulated Viscosity Index (VI): 161
Viscosity/ Temperature Coefficient (VTC): 0.81
VT ([email protected]/[email protected]): 5.24
 
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