RGS Front fork oil
- Thread starter andre g
- Start date
RGS1000RGS
Senior member
- Location
- Dorset, GB
Were the seals leaking?Really 300 ml SAE 10, just 150 came out
piranha-bro2
Hero member
- Location
- Melbourne
ATFQ I think you mean? 
Schurminater
Hero member
- Location
- Surrey Hills
any help?
Through the drain plug or out of the top with the fork off the bike?
Paul
The Sock
Hero member
- Location
- London, England
Yes, though some add more.
In my experience, the amount that comes out is always less than went in, particularly if it's some time since the oil was changed.
Yes
Paul
Alzero
Hero member
- Location
- DaNang Vietnam
Doesn’t filling the forks to a higher level give an air spring effect under heavy breaking?
piranha-bro2
Hero member
- Location
- Melbourne
Yes - has no effect on damping (which is controlled by viscosity - and internals).
That air spring effect isn't that profound from my experiences with small changes. I think you need to get close to hydro-locking before it gets really noticeable. What is important is making sure you have enough oil to completely cover the damping internals. Air bubbles don't dampen.
78jotadave
Hero member
I'm probably opening up a 'can of worms here but more oil in the forks makes them feel stiffer and harsher over bumps but makes them less prone to bottoming. Less oil makes them feel softer and more likely to bottom out over large bumps. The viscosity of the oil controls the speed of the action of the fork's internals. Using a greater volume of oil of a lighter viscosity firm up the feel of the forks while allowing them to respond more rapidly to bumps... then there are
the springs
the springs
Kinda echos my experience too, Dave.
FWIW, I'm currently running 400ml of 10 weight in my RGS Corsa and am happy with this. BUT I'm using Race Tech springs which are shorter* and fatter than the original Marzocchis.
* So need longer preload spacers to get the sag in range.
CLEMTOG
Hero member
"Doesn’t filling the forks to a higher level give an air spring effect under heavy breaking"
doubtfull, the tiny ball and spring in the centre of the Marzochi's top nut is there to relieve air pressure on compression, a lot of air can pass very quickly through a 3mm hole, the extension then causes a partial vacuum, which natural leakage of the seals takes care of.
CLEM
I have seen two bikes here that had the ball and spring missing from ONE LEG ONLY
doubtfull, the tiny ball and spring in the centre of the Marzochi's top nut is there to relieve air pressure on compression, a lot of air can pass very quickly through a 3mm hole, the extension then causes a partial vacuum, which natural leakage of the seals takes care of.
CLEM
I have seen two bikes here that had the ball and spring missing from ONE LEG ONLY