Something like this would probably fit, it's for a Kawasaki obviously and you might have to do a little work with the Dremel to make it fit , if I remember correctly the Yamaha cable is slightly bigger, no hill for a climber though.
Most of the Kawi cable holders are of a similar design to the one in the link and know I used a Kawi cable holder similar to that one with a Superjet cable on my Superjet build..
2004 JET SKI 900 STX (JT900-E1) - Cables. 2005 JET SKI 900 STX (JT900-E2) - Cables. 2006 JET SKI 900 STX (JT900E6F) - Cables. 2004 JET SKI STX-12F (JT1200-B2) - Cables. 2004 JET SKI STX-15F (JT1500-A1) - Cables.
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