I need a stiffer spring for my rear shock . I have a KTM390Duke, the O.E.M rear shock is diabolical so have done a modification suggested by someone in USA of fitting the rear shock from a Yamaha R6 ( 1998-2002). After some simple mods- making a new bush to accommodate the difference bolt sizes , and some shims to take up the difference widths of the swing arm mounting, I have found a huge improvement ( the R6 shock has both rebound and compression adjusters, the O.E.M shock on the KTM has no adjusters!) I have now realized that the spring fitted to my R6 shock is too 'soft' so I need a stiffer spring. I have been advised that at my weight 72Kg ( without leathers etc) I need to go up to the next rating, so need a spring rated in the 10 Kg or 600# See advice I was given here: "For a rear spring the stock (yellow) spring is good to about 140#. You will want to go up one spring rating on the rear, so something in the 10.something kg range, or 600#, depending on which spring company you source from. Depending on the miles on the shock (what's the bottom out bumper look like?) The spring might be tired and ready for replacement anyway even if it were the correct rating... But you are one under for sure!" I'm not familiar with the # system of spring ratings, I have found this place who makes springs and am considering ordering a spring from them, price is around £35 and made in England! ( K-tec price for spring is £85!) http://www.shock-factory.co.uk/sheffield-home. I am also considering getting the shock reconditioned as it's approx' 14 yrs old. Any recommendations for good service and quick turn around? Any advice or opinions welcome.
