RE: Redcat Racing Volcano Thread
I filled it so that it was concave, forming a depression just below the rim. The local hobby shop recommended 40 wt, so that is what I used.
On the opposite end of the shock body where the shaft comes in, there is another screw on cap with a hole in it for the shaft. What is the purpose of this cap? I thought about filling the shock as before and tightening the cap (shock body end), then turning it upside down and loosening the other cap (shaft end) to relieve any air while working the shock up and down.
My understanding is that the oil has some dampening effect, but is mainly used to control rebound after the shock has been compressed. Therefore, the shaft should be able to move freely without sticking in the shock body. If I use less oil, that would defeat the purpose since there would be excess air in the form of bubbles in the shock. I might just try some different techniques until I get it right.