Ive tried searching but have issues finding info on the actual spring.
I have a FT and just want a yellow spring without spending Ohlins money.
Does anyone know the size of the spring and where to get a replacement?
Yep, that'd be the easiest route for sure. The factory spring tapers toward the top, so you'll need a spacer sized just so in order to fit a new spring to the shock body. Take a good look at your bike and you'll see what I mean. More here if you like: