New suspension settings

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Fred W

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Preload doesn't seem to have any effect on when the transition from the soft to hard rate occurs because of the compression of the top out springs and because preload does not change the springs total compression once static weight is applied.
No, preload doesn't affect where the spring rate transition occurs because, with a given amount of weight load, the spring will always be compressed the same amount at rest, so the transition will always be the same distance from rest. The at rest point will vary by the amount of preload (aka change ride height).

 

SCB

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Preload doesn't seem to have any effect on when the transition from the soft to hard rate occurs because of the compression of the top out springs and because preload does not change the springs total compression once static weight is applied.
No, preload doesn't affect where the spring rate transition occurs because, with a given amount of weight load, the spring will always be compressed the same amount at rest, so the transition will always be the same distance from rest. The at rest point will vary by the amount of preload (aka change ride height).
Well, again considering the fact that there is also an air spring effect, adding preload will extend the fork leg, reducing the air pressure in the fork. You will, in effect, be transferring weight from the air spring to the mechanical spring. The net result will be a somewhat MORE compressed mechanical spring.

A corollary of this is adding 10mm of preload will not raise the ride height by a full 10mm. It will come up some lesser amount due to the reduced contribution from the air spring and the associated increased compression of the mechanical spring.

 

eflyguy

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Oil level, and hence air volume, is absolutely used to tune suspension on race bikes - both dirt and asphalt.

 

BluJ

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Just discovered that my compression is a max 12 clicks out on the right fork, and 28 on the other. Hmmmm!

 

BluJ

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You must be thinking of the rebound knobs up top. Don't see no screws near the compression adjusters at the bottom of the forks.

 

Antwon412

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Just picked up am 04. It’s in perfect condition. I’ve adjusted the suspension but I cam across an issue that I haven’t seen addressed here.

When adjusting my rear shock, it’s supposed to have 20 clicks of adjustment.

I counted 40.

What gives?

It APPEARS to be the stock shock. Am I just am idiot?

 

Versatek6

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I have found this thread most helpful. Thank you!

With two years since the last post, I would like to contribute to the knowledge base: I went searching to learn more, to help diagnose what I was experiencing, and found an excellent thread on the Superbike-Coach.com website.

https://www.superbike-coach.com/coachs-blog/coachs-motorcycle-support/motorcycle-suspension-guide

About halfway down the page is a diagnostic section titled, "SUSPENSION DAMPING SYMPTOMS," which explains what you feel when there are setup issues. I found that the the oversteer I was having was caused by too much damping, so a few more clicks out and it's much improved. I'm now starting to dial things in better using the information presented there.

I hope someone else finds this useful.

 

hANNAbONE

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Just dialed in my 2014 "A" front and rear and it runs like it's on rails.!

Many thanks for those that took the time to get this info to the masses.

Very helpful and really makes this heavy girl light on her feet.

Thank you Thank you Thank you -- Especially MadRussian

 

SFZX

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Its amazing how much conjecture there is about suspension settings. Listen to videos by Dave Moss and learn from the guy that tunes thousands of race bikes for track riders everywhere. There is no guess work to this stuff at all. First set preload by measuring rider sag for touring bike usually about 40 mm. Track should be less. If your spring rate is correct you should achieve, with this setting, at least 15mm of static sag( be able to lift the bike to top out suspension). now go to rebound and stand next to the bike firmly compress and let the bike come up quickly as possible. watch for bouncing, you want it to come up quickly as possible but not a hint of a second bounce. So close rebound till you get this scenario. Now use a zip tie on the fork to set compression setting just to the point that your not bottoming out on hard bumps but at least a few mm away from that and never go softer than this, only tighter or more compression damping from here. The perfect case scenario here is keeping the average deflection in the middle third of your full travel the bike has.
Now all this will change depending on how old your oil is and what weight your using. Learn more about different oils from Moss to he has charts that will give you true oil sae weight by brand and listed sae weight on the bottle. Some oils will be more stabilized as temp changes than others his chart will give this info as well.
 

SFZX

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everyone on this forum should look at that video for sure, it will wet their appetite for more suspension knowledge. Biggest eye opening event in my riding was discovering what proper suspension can do for your riding, even way more important than custom exhausts and other mods in my mind.
 
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