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Discussion Starter #1
Trying the search function but having a very difficult time wrapping my head around this.

I'm working to get my sag within acceptable limits (210lbs in full winter gear) but having some difficulty knowing what is acceptable or if I'm going about this correctly. I've seen some people consider anything from 25 to 40mm of sag the goal, with 35 as a mean of sorts.

I'm coming to 38 on each end maxed on preload. I figured I'd be at the heavier end for stock springs, but will changing them out be necessary at my weight for a casual street rider?
 

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If you're in your desired window of sag then you're fine, just ride.
If you can't achieve it because you run out of adjustment then yes, change your springs for your weight.
I'm riding the F model which has slightly more preload from factory, 225lbs without riding gear on and preload in the front was spot on.
 

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Discussion Starter #4
If you're in your desired window of sag then you're fine, just ride.
If you can't achieve it because you run out of adjustment then yes, change your springs for your weight.
I'm riding the F model which has slightly more preload from factory, 225lbs without riding gear on and preload in the front was spot on.
Most of my confusion comes from no solid consensus on what proper sag is. 35 is thrown around a lot for sport bikes in general but if that is true for our bikes I didn't realize the stock springs would be so weak.
You're on stock springs and preload settings? What is your sag measurement at that weight?
 

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Aren't the standards springs progressive front and rear?
I know where you are coming from but normally I have only dealt with linear springs set for my weight. In those circumstances you only need to set your static sag. 10mm ish. the rest of your ride is sorted out with your rebound and compression settings.
If the spring is soft for your weight it will feel like the front end is too high when coming out of corners and want to run wide on the power. If it's too hard you'll have a really uncomfortable ride and the bike will try to tank slap over the smallest bump under power
Are you using the standard shock or have you bought something which has been upgraded? There are a few sites about if you need to know what is the correct spring weight for your weight
Don't get too hung up on the numbers. They are only ball park figures to get you started. Handling is key
 

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Most of my confusion comes from no solid consensus on what proper sag is. 35 is thrown around a lot for sport bikes in general but if that is true for our bikes I didn't realize the stock springs would be so weak.
You're on stock springs and preload settings? What is your sag measurement at that weight?
Stock springs and 30 to 40mm is correct.
I think I ended up with 35 front and 38 rear, I've now replaced the rear shock and I have infinitely more adjustment.
 

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Discussion Starter #7
Stock springs and 30 to 40mm is correct.
I think I ended up with 35 front and 38 rear, I've now replaced the rear shock and I have infinitely more adjustment.
Alright it sounds like I'm not totally off base then. My suspension is completely stock as of now. I don't know much about sport bike suspension/handling as I'm still fresh to this, but nothing stuck out as "wrong" to me other than some bouncing in the rear which was remedied with a touch extra rebound.

I only starting reading up on this and fiddling after seeing so many people sing the praises of life changing improvement from setting their sag correctly
 

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Alright it sounds like I'm not totally off base then. My suspension is completely stock as of now. I don't know much about sport bike suspension/handling as I'm still fresh to this, but nothing stuck out as "wrong" to me other than some bouncing in the rear which was remedied with a touch extra rebound.

I only starting reading up on this and fiddling after seeing so many people sing the praises of life changing improvement from setting their sag correctly
Definitely on the right track. Sag is the meat and potatoes, when that's set correctly you season to taste with damping which is more trial and error, ride and adjust.
 

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will changing them out be necessary at my weight for a casual street rider?
No.
The recommended sag in the rear is 30-35mm(Andrew Trevitt, Sportbike Suspension Tuning, p.42). IMHO a 3mm difference will not matter on the street to a casual rider. Most bikes, the same is true on the front. I weigh 245 and I thought I had the correct sag with my preload adjusted all the way up (maximum, screwed in). But going from memory a couple months ago.
In those circumstances you only need to set your static sag. 10mm ish.
But that means you only have 10mm before you top out on the suspension. That doesn't make sense to me. It seems you want more than 10mm available before that happens.
 

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No.
The recommended sag in the rear is 30-35mm(Andrew Trevitt, Sportbike Suspension Tuning, p.42). IMHO a 3mm difference will not matter on the street to a casual rider. Most bikes, the same is true on the front. I weigh 245 and I thought I had the correct sag with my preload adjusted all the way up (maximum, screwed in). But going from memory a couple months ago.

But that means you only have 10mm before you top out on the suspension. That doesn't make sense to me. It seems you want more than 10mm available before that happens.
Soz,
Thats me getting muddled up with terminology. I'm referring to the bike without a rider and under its own weight.
Sorry to add confusion:)(y)
 

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Discussion Starter #13
Soz,
Thats me getting muddled up with terminology. I'm referring to the bike without a rider and under its own weight.
Sorry to add confusion:)(y)
I had also read in a few places that the static sag : rider sag ratio is a better indicator of proper spring for weight than rider sag : preload setting (ie. My situation of max preload and slightly over 35mm sag).

Yet another figure I wouldn't be able to call precisely though.
 

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Thats me getting muddled up with terminology. I'm referring to the bike without a rider and under its own weight.
Sorry to add confusion:)(y)
That makes more sense. Thanks for clarifying.
 

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The best way to go is to replace the notoriously deficient shock with a replacement, many are named in this forum. I have chosen K Tech, and accepted their recommendation for spring rate and sag.
It is pricey, I spent more for the GSXS K Tech shock than a complete set of Bilsteins for my C5 Corvette.
I have used Race Tech in the past for an older sport bike, front and rear, spent a lot but was very happy with the result. I am hoping that rear only will do it for my 2016 GSX S1000.
 

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Like emullick said get K-tech or at least a shock sprung for your weight and while your at it may as well get the front done as well.
I always set the rebound in the middle of the setting and tweak from there it’s usually close so not much adjusting or just leave it.
As for compression I set it really soft for the crap roads but if your doing any track riding I set the rear in the middle and front one turn out from all the way in.
 

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Discussion Starter #19
I know some have issues with the lack of damping adjustment on the oem rear shock but I'm specifically referring to preload and sag. As I understand it compression and rebound (even in the terrible oem shock) has 0 impact on rider sag
 
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