Also Z , I have 2 last year's springs from KAZ with spring rate of 27.2 N/mm .Given that I require only around ~32mm of travel on spring , I can cut those in about half or as much as required to get me to ~51 N/mm . Infact I think better would be to cut it to give me around ~45 since I can always increase stiffness with spacers but cannot decrease it. So perhaps I would not have to search for motorbike springs.