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Discussion Starter #1
From what Ive been reading on here, you want about 5 to 10mm more sag up front as opposed to the rear. Is this verified from other racers (on a track)? Ive been running about 25 rear/ 25 front. What will i notice if I go 25 rear/ 30 front?
 

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Different dynamics and loading. To understand this, you need a good understanding of harmonics/vibrations/oscillations and the height/loading factors for each dynamic system. There's a baseline laid out in numerous placed on the forum and on YouTube. It's good reading and knowledge to acquire without spending $3,000 on a vibrations class for a surface level understading.
 

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I have my masters in engineering so I have some knowledge in the area. Is there a specific book you refer to? As with any forum, I'm trying to understand if the +5/10 front is information or misinformation. Are professional race teams also running higher in the front or is this generally accepted info on a forum (second hand knowledge)?

Any specific material suggestions is much appreciated!

Thanks,
Chris
 

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Discussion Starter #4
As I have read, more front sag slows steering response; would an even front/rear sag be better on a short track?
 

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I have my masters in engineering so I have some knowledge in the area. Is there a specific book you refer to? As with any forum, I'm trying to understand if the +5/10 front is information or misinformation. Are professional race teams also running higher in the front or is this generally accepted info on a forum (second hand knowledge)?

Any specific material suggestions is much appreciated!
I wouldnt worry about what "race" teams are running vs. what you feel at your particular pace & equipment. Also there can be a dramatic difference in the fork setup for 2 guys of the same pace.

Some tracks require a softer spring rate other tracks may require a higher spring rate regardless of pace. Other factors may be elevation changes or camber of turns.
Also your sag is directly related to how much travel your shock has.
For instance... a stock fork may only have 90mm of usable travel vs a modified cart equipped fork may offer upwards of 140mm.

The most important part of setup is NOTES. Most of the racers I know have binders with track maps and pages of settings/pressures, spring rates, etc. Also a good suspension tuner is worth their salt...
 

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Discussion Starter #7 (Edited)
Thank you both. On my track day tomorrow, there is a suspension guy that is familiar with the track and my riding. I agree with you, turboblew, I think it is track dependent. I'll update as to what I learn. Thanks again.
 

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The main thing regarding sag as stated by turboblew is it boils down to usable amount of travel for the suspension for the person using the machine.
 

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Sag is a mathematical equation of overall stroke. You have 120m of fork travel so the middle 1/3 if that total stroke would set you around 38-40mm.

The rear shock travel is significantly less so the norm is 30mm on most R-type sportbikes.

Some bikes require a little more, some a little less and at the point where you are riding within a few seconds of any given lap record then sag numbers generally go right out the window as we laser focus the bikes suspension to ride specifically within a very small window of operation at that pace.
 
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