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         Better too slack - but not hopping off the sprocket slack!
          
          Too tight puts strain on the output bearing (front sprocket) - I've picked up a number of bikes in the past with busted cases around the sprocket because the owner had the chain too tight.
          
          Co-incidentally both bikes were MZs (one an ETZ, the other a Supa 5) but different owners. The MZs didn't have a reputation for sprocket bearing problems (the early 4-speeds did for mains). The only thing I can think of was the chains were fully enclosed (a great system) and the owners couldn't see the chain and simply mis-adjusted them over their ownership. 
         
        
        
       
         __________________
          Simon
          
          Brighton, UK 
         
        
        
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