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Removed rear shock this morning , wound pre load on spring 3 full turns and fitted 2 x 1.5mm washer / spacers on top of shock feels good anybody else done this , what do you think ?
 

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Assuming the spring is roughly correct for your weight, the preload is to be adjusted to obtain correct rear sag. With you sitting normally on the bike, it should "sag" 1/3 of total wheel travel or 1/3 x 4.7" = 1 1/2".
Metric conversion available on special request.
 

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So, what you have done is changed the geometry - nothing more and nothing less.

By raising the rear you have reduced the rake and lessened the trail. That will make the motorcycle turn in easier.....but there is a really bad downside of this - instability. There is a way to check to see:

Start by making sure your front tire pressure is correct. Then you should find a familiar road with a long sweeping corner. Something you can settle into. Highway cloverleafs can be helpful here if they aren't too banked. When you are in the corner try to slowly release your grip on bars and feel what the motorcycle tries to do. Be mindful of it trying to fold the front end, in other words you are applying input that keeps the front from falling into the corner. What you want is geometry that would allow you to completely let go of the bars and it will track the same line.

I hope this helps.
 

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BirdDog
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Can’t speak for your preload but I shimmed 4mm many years ago which greatly improved turn-in and performance handling. No issues in over 100,000 miles with this simple mod!
 

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So, what you have done is changed the geometry - nothing more and nothing less.

By raising the rear you have reduced the rake and lessened the trail. That will make the motorcycle turn in easier.....but there is a really bad downside of this - instability. There is a way to check to see:

Start by making sure your front tire pressure is correct. Then you should find a familiar road with a long sweeping corner. Something you can settle into. Highway cloverleafs can be helpful here if they aren't too banked. When you are in the corner try to slowly release your grip on bars and feel what the motorcycle tries to do. Be mindful of it trying to fold the front end, in other words you are applying input that keeps the front from falling into the corner. What you want is geometry that would allow you to completely let go of the bars and it will track the same line.

I hope this helps.
What you have described is exactly how it should feel and why I removed my 6mm shim. The feel i want is a neutral and balanced feel mid corner. The shim did improve this on my worn out shock, but when i bolted in a new shock with the right spring and preload set, the shim came out. The bike tips in easy and feels nice from vertical, to lean and back. (y)
 
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