Re: AMP Research F4 Blt Factory Rebuilt for Sale £200
Thanks for your interest. I see you are in Canada. I'm in Ontario between London and Hamilton. I apologize, I just looked but can't seem to locate the other springs. According to the parts manual there were 3 spring tensions available; 350#, 400# and 450#. My son was a downhill rider. I suspect the dark green are the 450#. AMP Research could probably tell you. I got parts and service manuals from the AMP Research website.
PS - our family of 4 did a lot of riding and racing back in the '90's. I did all the maintenance and kept most of the used parts I replaced. If there is a retro item that you are looking for I may have one (or more!).