Stock oil viscosity in Koni Sport/Yellow shocks

[zaibatsu]

Just wondering if anyone knows the viscosity of the Koni Sport stock oil, preferably in cSt@40*C, or otherwise just the brand and weight would do.

I've heard the stock oil is from Shell and an internal part number has a 15 in it which would suggest a 15wt but this is very vague and would appreciate confirmation from anyone that knows.

 

[slacktide_bitog]

It's possible that they use a few different viscosities. Some of them also have pressurized gas, some don't.

15w seems kind of thick for shocks that have to work when freezing cold.

You could always drain a shock and get a VOA

 

[dailydriver]

I would just send them to a known, reputable, factory authorised, Koni re-builder (like True Choice Sports or such), and tell them what you want to do with them (use, conditions, spring rates, car weight, weight distribution, etc.).

Let them re-valve them, reseal them, and replace with the correct weight and type oil, and new end bushings/heims.

Or are you just curious as to what is in your Sports?

 

[userfriendly]

An ISO 10 on the light side and ISO 15-22 is about
right down the middle.
ATFs are typically ISO 26 for Dex 6 and up to
38-42 for multi vehicle ATFs.

Check with your motorcycle dealership.
Some fork and shock oils list their ISO grades.

I think that shopping for the highest VI is a mistake
with shock and fork oils, Shell's LGF, landing gear
fluid, Iso 13.5 being about the highest I've seen.

AS VI goes up, boiling points go down. (flash points)
An overheated shock will pump up and go as hard as a
rock with a super high VI low flash oil in it.

The best thing about adjustable suspensions,
is that you don't have to nail the viscosity on the
1st try.
When I used to do forks on dirt bikes I kept a pail
of R+O 10, 22 and 46 around.
The cost? About $2.50 a liter.
The Aero Shell LGF would be perfect for a snowmobile,
because the fluid will remain fluid at temperatures
you will not venture outside in.

 

[tdi-rick]

Standard Koni oil is a mineral fluid by Shell, I actually have some in the shed.

I bought some a very long time ago and wasn't privelidged to the specs so did some basic viscometric tests by measuring how fast it drained through an orifice at various temps and the closest syn fluid I matched it with @40*C was Silkolene Pro RSF 5.

This was confirmed as being very, very close at 40*C by the Koni importer I bought the oil and parts through.