Suspension fluid - Oil vs. Silicone??

[Surestick]

I was doing research for what 5wt fluid was the best for me to use in an upcoming fork rebuild (It's going to be either Redline Lightweight or Motul Shock Oil depending on which I can get easiest).
While doing internet searches I discovered that RC cars seem to use silicone fluid instead of oil in their dampers. They also use much heavier viscosity fluid than is used in motorcycle forks.

Curiosity led to a bit more research and some mention of silicone-filled dampers for cars but no availability of silicone fluid for rebuilding motorcycle suspension despite the claim in the RC community that silicone fluid is better than oil as it retains its viscosity better with temperature changes, lasts longer and leads to longer seal life.

There doesn't appear to be any mention of silicone fluid being available in lower viscosity for motorcycle forks and I'm curious as to why this is.

 

[Mackelroy]

I cant answer the oil verses silicone.

But what ever oil you use, viscosity can vary a lot amongst brands, and the whole platform will react differently. one companies 10 weight might be closer to another companies 5 weight

motul could work best for you or showa may work best, its all how the oil reacts to the present orifices ( all suspension fluids work as far as function). And if dealing with cartridge forks, they are very sensitive to oil height, compared to non cartridge.

So first question to ask, How do I like the present action, and what is wrong or right with it. Has the oil been changed before what weight and type is in it, and are you very familiar with testing this set up.

just things to consider, cause when you change oil to something different, expect the platform to change

 

[Surestick]

Originally Posted By: Mackelroy
I cant answer the oil verses silicone.

But what ever oil you use, viscosity can vary a lot amongst brands, and the whole platform will react differently. one companies 10 weight might be closer to another companies 5 weight

motul could work best for you or showa may work best, its all how the oil reacts to the present orifices ( all suspension fluids work as far as function). And if dealing with cartridge forks, they are very sensitive to oil height, compared to non cartridge.

So first question to ask, How do I like the present action, and what is wrong or right with it. Has the oil been changed before what weight and type is in it, and are you very familiar with testing this set up.

just things to consider, cause when you change oil to something different, expect the platform to change



Yup, taken into account.

I was more curious as to why, if the RC crowd claim the silicone stuff is so much better, it hasn't been marketed to the motorcycle crowd.

 

[Smoky14]

The cost is probably the biggest factor, a few cc for an RC vs a couple pints for a MC.

That being said, I usually prefer shock oil over fork oil.

YMMV

Smoky

 

[BigCahuna]

I did the fork oil on a '82 Goldwing, and the factory recommended fluid was ATF.When I did my '96 Harley, I used Harley's fluid. Looked and smelled the same as ATF. No weight was listed on the bottle.,,

 

[Surestick]

Originally Posted By: Smoky14
The cost is probably the biggest factor, a few cc for an RC vs a couple pints for a MC.

That being said, I usually prefer shock oil over fork oil.

YMMV

Smoky


Both the Redline and the Motul Shock Oil are synthetic and both have a VI in the 400s VS. fork oils which mostly have a lower VI in the 100s.

I thought cost too but then, you know there'd be a market for something that was "the best" even it it was a hundred or two a fill, especially if it promised to last longer as well.

Silicone oil
At $2.71 for two ounces a 16oz bottle would be $21.68 versus $10.95 for 16oz of Redline suspension fluid (from their website). Not exactly a break the bank difference.