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Hi, I have recently purchased a new GSXS1000 and was seeking some advice re: suspension settings.

For me, I find the rear suspension a bit hard and wondered if anyone had any advice or a similar experience.

I'm 13 stone or approx 82kgs.

Any idea what setup would suit my weight, and how I would go about adjusting it.

Steve.
 

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Stevechesterton, I reduced rear rebound by adding an extra 1/2 to 3/4 turn out from stock and added one more turn out from stock on front rebound compression (look in manual and it shows where the adjustment screws are--I did it anyone can do it :)). This seemed to help. It probably needs a new shock, but philosophically, if we wanted to spend mass quantities of dollars wouldn't we have bought a different bike? (BTW, I'm about 79 kg.)
 

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Its no race bike suspension for sure. But for our weight. I'm about 82kg too. I find it ideal for twistiest and commuting. In fact, a little soft (for my regular preference) This bike's suspension reacts very well to the setting changes that we have. But since we dont have a rear compression adjuster, I just match the front comp. rate with the rear.

We can all just give rough ball park figures but it will also depend on riding style and how you sit on the bike. The best way is to set it up correctly. The stock suspension set up is in the manual, so you can always go back to that.

Here is a good vid that shows how to set up suspension. This is part 1, there is a part 2. This was recommended on one of the threads before and looks like a great guide.
https://www.youtube.com/watch?v=QG1KPuOzvLg

You may want to combine that with this link that explains symptoms of given settings.
Suspension Tuning Guide ? ROADRACE MOTORCYCLES

Ride safe dude
 

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it's a wilbers 641, has external reservoir and hi-/lo speed compression damping adjustment, as well as rebound adjustemnet, height adjustment and hydraulik spring preload.
the spring prload hydraulik part comes with a part to mount it at the exhaust screw, very nice.
the reservoir is under the pillion seta.everything fits nicely, without the need to modify anything.
i ordered the shock with a custom spring rate of 80N/mm. this is the softest spring allowed for the german TÜV. i'm really happy with it, because i found the original shock way too hard. i'm about 20 km/h faster on my reference track, too. :)
Still not enoug pictures, but you may find some on the wilbers site, if they already have it there.
i ordered ine on the dortmund show in March this year, there i could talk to the technical manager. nice guys there....
 

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i stuck a wilbers 641 on mine with TD cartridges in the front...best mod for the bike. I had the same experience that after upgrading the rear, the front was obviously inferior. The bike is now soo much smoother.....and thats the main problem with the oem setup. No matter how well you adjust it, the high speed dampening sucks. This translates to a rougher ride and more bumpy/vibration feel, might always feel hard. Cheaper shocks just cant move the oil back and forth fast enough.
 

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I know it goes against the grain but I pay no attention to SAG. As far as I'm concerned that just tells you if you have the correct springs for your weight. I just adjust the suspension where it feels and performs the best for me. Every time I go to the trouble to set the SAG according to the so called experts the suspension never seems right. My last two bikes I actually changed the springs to fit my weight and still I got better results by not going with the SAG adjustments. Just sayin! BTW you are correct about where you sit on the bike.
I was a dirt rider for many years and with every bike I owned the center balance was as close to the tank as possible. Most of the sport bikes I've owned handle better if I push up close to the tank.
 

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I know it goes against the grain but I pay no attention to SAG. As far as I'm concerned that just tells you if you have the correct springs for your weight. I just adjust the suspension where it feels and performs the best for me. Every time I go to the trouble to set the SAG according to the so called experts the suspension never seems right. My last two bikes I actually changed the springs to fit my weight and still I got better results by not going with the SAG adjustments. Just sayin! BTW you are correct about where you sit on the bike.
I was a dirt rider for many years and with every bike I owned the center balance was as close to the tank as possible. Most of the sport bikes I've owned handle better if I push up close to the tank.
What do real experts say about sag numbers? Isn't it really there is no such thing as a precise number and its all personal preference and the conditions under which you ride. Races run less sag because there are no potholes in a race track (or shouldn't be in a decent one), and want maximum travel under very hard braking.

BUT, for the average person starting with well proven 'rule of thumb' numbers front and back are a pretty handy place to start. And someone experiencing a harsh ride in the rear, don't overlook running lower tire pressure, and increasing pre-load. Both will soften the suspension. Tire pressure very noticeably, and increasing pre-load just a bit.

P.S Think hard before someone feels a need to say increasing preload (reducing sag) in the rear won't soften the ride. It will, just how much is the issue.
 

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Agreed on the tire pressure but you got it backwards on the preload. Even the GSX owners manual says to stiffen the ride you should increase the preload. I can't recall any of the bikes I've owned that increasing the spring load made the bike more compliant. I would suggest that you turn up the preload on the rear shock and see what happens. I'm certain it will not make for a softer ride.
 

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Agreed on the tire pressure but you got it backwards on the preload. Even the GSX owners manual says to stiffen the ride you should increase the preload. I can't recall any of the bikes I've owned that increasing the spring load made the bike more compliant. I would suggest that you turn up the preload on the rear shock and see what happens. I'm certain it will not make for a softer ride.
First up, forget what you read about how to adjust motorcycle suspension in ANY manufacturers owners manual. About the only thing they generally have correct is what each 'thing' does, and which way you turn it to increase or decrease it. Whoever writes those sections of the owners manuals, hasn't the faintest clue how to adjust a motorcycle suspension. Much of it is just plain WRONG!

Now start with a universal truth, altering spring pre-load in any direction "DOES NOT STIFFEN OR WEAKEN A SUSPENSION SPRING (front or back)". Repeat that truth several times to remember it for life. OK, there is one exception, and only one exception. And that is when the shock absorber or front fork is fully extended (completely topped out). All pre-load does (other than when the suspension is fully extended) is make the bike sit higher or lower in its suspension travel. That's ALL it does.

Regardless of the amount of preload put on a suspension spring it will always compress to EXACTLY the same compressed spring length as the weight it is being asked to support (bike and rider). If the combined weight of bike and rider the spring has to support are say 150Kg, using an extreme example you could put 149Kg of preload on the spring, and when the weight of bike and rider are stuck onto the spring it will compress to EXACTLY the same length as it would if there were ZERO preload on the spring. The only difference is that it will just compress a very tiny bit. The spring will always compress or expand till it's force equals the weight it has to support (in our example 150 Kg). And the spring will only exert 150Kg at one length.

Following so far? Preload itself does not directly make a spring softer or harder, more compliant or less compliant. All it does is set the static ride height of the motorcycle.

BUT ........ connecting the shock absorber spring to the back wheel via the rear swing arm is a progressive suspension link. While the rear spring is typically linear in design (spring gets stronger at a constant rate when compressed) the job of the progressive link is to make it behave in a progressive manner (get stronger at a faster rate) as the suspension goes down in its travel length. The lower the rear suspension sits in its travel range the stronger the 'effective' spring rate at the wheel to any movement, due to the progressive linkage. The opposite also applies, the higher the bike sits in its travel range, the lower the 'effective' spring rate to any movement (again due to the progressive linkage).

In summary, pre-load does not in any way alter the spring tension. But due to the presence of a progressive linkage, the higher a bike sits in its suspension travel the lower the 'effective' spring rate, and the more compliant the ride.
 

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We'll have to agree to disagree. As I said, increase the preload on your bike and let us know if it's softer or stiffer.
I wasn't really trying to convince you. I knew you probably wouldn't even take the time to read what I typed, let alone try to understand it.

I posted the detailed explanation for the benefit of others who may want to learn something new. Due to the progressively linkage, making the bike sit higher in its suspension travel (by increasing the preload) reduces the 'effective spring rate' at the wheel. Very simple to understand actually. If people want to understand more, this is a more detailed explanation of preload and leverage ratios

Motorcycle Suspension - Sag and Preload

One comment in the article I partially like is "So if someone tells you that you should reduce your preload to make the bike feel less harsh, they probably don’t have a clue."
 

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I agree that Preload cannot make the suspension softer or harder unless as you state the rear suspension linkage itself makes the effective spring rate harder as the bike moves down/ swingarm moves up

OR

less preload.on the forks means that you are using more travel on the forks and compressing the air in the forks causes the effective spring rate to increase as the forks compress more, and compressing a gas is certainty not like a linear spring
 

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I agree that Preload cannot make the suspension softer or harder unless as you state the rear suspension linkage itself makes the effective spring rate harder as the bike moves down/ swingarm moves up

OR

less preload.on the forks means that you are using more travel on the forks and compressing the air in the forks causes the effective spring rate to increase as the forks compress more, and compressing a gas is certainty not like a linear spring
Rear suspension
Changing pre-load in the rear doesn't change the spring rate itself, but it changes the 'effective' spring rate at the wheel. And it's the effective spring rate at the wheel that is important in terms of ride compliance. And at the wheel you have a progressive effective spring rate (due to the use of a progressive linkage). As the wheel come up, the effective spring rate exponentially increases. This same effect occurs when rather then the wheel rising up (over a bump say), the bike is dropped lower in its suspension travel by decreasing spring pre-load. It's just the other 'end' moving.

Decreasing rear pre-load lowers the bike and in doing so increases the rear-wheel effective spring rate (due to the progressive linkage), giving a harder ride. Increasing rear preload raises the bike and in doing so decreases the rear-wheel effective spring rate, and gives a softer ride. Just how much is the only unknown, as I said in my first post

Front suspension
Less pre-load means less airspace in the forks. Less air being compressed creates a MORE progressive air spring rate and a firmer ride in the last 1/3 of fork travel.

So in both the front and rear suspension, decreasing pre-load as is commonly touted as a solution on the internet (and by some suspension 'specialists') does not give a softer ride. If anything it will do the EXACT opposite and give a firmer ride. For the exact same reasons, increasing pre-load with give a softer ride. In the rear due to the progressive leverage ratios of the rear linkage, and in the front due to the increased volume of air in the forks.
 

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I did read it and it all sounds good BUT all I know is that every bike I've owned throughout 40 years of off and on road riding that every time I increase the preload on a bike the back or front gets more firm and every time I decrease the front or back preload the suspension softens up. That's basically all I need to know about springs and preload. I don't want to be argumentative but that theory has always worked for me. I've owned Triumphs, BSAs, CZs and Huskys with twin rear shocks and many rear single shock bikes like my GSX1000F and it ALWAYS works this way.
 

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everything in life come,s down to the bottom line....1 setting is a nice soft enjoyable ride...2 gets firmer and 3 to 5 feels like a harsh bumpy ride that i dont enjoy and is very edgy at fast highway speeds..thats all i need to know
 
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