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Discussion Starter · #1 ·
My last post about using Dave Moss Tuning as a guide for adjusting suspension disapeared, not sure why. Anyways.... I wanted to getvthe most out of this stock suspension without springing for a 500-1000 dollar upgrade kit. I learned alot about suspension settings from Dave Moss Tuning and set to work doing what I could. His recommended settings for regular use are 15-25mm Static Sag in the front and 30-33% fork travel as the setting for total sag with rider. For us thats 34-38mm total sag because our ACTUAL fork travel on the Z650 is only 115 mm. For the rear he recommends 10-15mm static sag and and for us 39-43 mm of total sag with rider. I was able to get these dialed in using a combination of rear preload and fork height adjustment but there is a bottom out problem because the suspension is "soft". What I came to realize is that a common misconception for our bikes is that the spring is at fault. No. The truth is (in my case and utilizing the tools I got from weeks of research) that our springs are fine. Our FLUID is to thin. 10 weight fork oil is not satisfactory for anyone over 140 pounds. At 180 no wonder I was bottoming under hard breaking. Doing the math using our actual fork travel and geometry relative to the triple tree clamp, I also found that the preload spacer is applying too much preload. In order to get a perfect setup geometrically one would have to move the forks in the triple tree clamps way too high or run out of room moving it down low. So..... Heres what I did.

I used a 1 inch diameter PVC as a replacement preload spacer. I cut it 10mm shorter than the stock spacer (to remove some preload) and replaced it while also changing to 15 wt fork oil.


No more bouncing around up front. Not only that, I was able to dial in those "perfect" settings provided by Dave Moss. The only other thing I did was move the forks down in the clamps by 2mm (stock is 6, so mine are at 4) to fine tune the geometry and get me RIGHT in the middle of his specs.

What did it cost?

1.30 PVC
15.95 Fork oil
Time and effort.

Let me know if you have any questions, just thought I'd let everyone know we can make our suspensions better on the cheap. I plan on buying a real upgrade kit later but I took this as a personal challenge to get the most out of what kawasaki gave us!
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