I purchased my 55 rc3 Ti with an ETA cartridge installed. There was one extremely soft (compress it most of the way with your hands) spring installed on the eta side, and no spring on the RC3 side. The fork required lots of air preload to even ride, and the quality of the travel was crap.
I made a flat end on a vanilla 36 spring and ran it single spring on the eta side, but ramp up was wonky and the spring took up too much volume to allow full travel and have enough oil for eta function.
In a moment of frustration, and with a case of the urge to tinker after another fit bladder failure on my van 36 rc2, I went at it.
Now, with one soft spring from an 2007 era 66/z1, the light blue 250mm long spring) on the rc3 side, and the light ETA assist spring on the ETA side, this is the best 160mm fork I have ever run.
The fork sags 25% with my 175lb on the bike. No air preload in either chamber, very little coil preload.
Slamming the front end down in the parking lot, I can use 90% of the travel. Taking a 3' drop at whatever speed it takes to spin out a 34-12 gear, I had 3/4 an inch of safety travel in reserve.
Photos and video to come after more testing.
I know there are some die hards on here who would appreciate such a thing.
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