Hello Wallstreet and welcome to kz1300.com.
I don’t have a ZX11 cam chain tensioner, and I’m not sure if what you are proposing would be a safe modification. I think that without the spring in place, there would’ve some ‘chattering’ of the mechanism, which is undesirable. Have you searched this forum for cam chain tensioner information? There is enough to keep you reading for at least one hour! So many differing opinions on the best solution to the flawed original design. I share your concern about the ZX11 spring strength being too great. To my mind, it is not as simple as cutting 10mm off the spring length to achieve an acceptable pressure on the tensioner assembly. Yet, many knowledgeable 1300 owners put their trust in that solution. I have not yet commenced the restoration of my A4 model, but when the time comes, my inclination is to retain the original tensioner, though with one small change - to the 6mm bolt / set screw in the side of the tensioner - I shall replace that with a longer one ( with turned down diameter at the end) so that the tensioner shaft can be locked in position when it has taken up the slack in the chain. The bolt needs to be long enough so that a lock but an be tightened against the tensioner body.
I have used the original tensioner with one modification. I have changed the 6 mm. original limiter bolt to one which is ca. 10 mm longer and have a locknut in it. I set the tensioner when engine is hot and then use the longer bolt to lock the shaft, tighten the locknut. Then check once every 3000 miles/5000 km. Has worked fine for me the past 30.000 km.