GSX-R600 K9 suspension settings [Archive]

View Full Version : GSX-R600 K9 suspension settings

jamjam

13th July 2010, 16:02

I want to get an idea of what kind of suspension settings people have found work for them on the new gixxer 600's. I've been tampering with mine and think i am in the right ball park figure for road use but not quite there yet. Sag is set so it's really compression and rebound i'm interested in. I am 75kg and riding solo. Generally my settings are on the softer side of the half way mark or factory settings (ie turned more than half way out counter clockwise with slight variances as i see fit). Does anyone wanna chuck up their settings that they've found work quite well for them.

slofox

13th July 2010, 16:06

Haven't meddled with the settings on the K8 yet - but might soften it a little sometime soon...

dipshit

14th July 2010, 12:30

I am 75kg and riding solo.

I am the same weight and the first thing I did was swap out the standard 9.4 spring on the shock for a 8.5 one.

It was way too hard in the rear with the standard spring for me.

slofox

14th July 2010, 12:36

I am the same weight and the first thing I did was swap out the standard 9.4 spring on the shock for a 8.5 one.

It was way too hard in the rear with the standard spring for me.

72kg, me. I do find the back a little bouncy at times...trouble is I am comparing with the SV still - so it still feels wayyyyy more betterer.

jamjam

14th July 2010, 16:28

i would agree with the little bouncy in the rear. Many people do suggest swapping out back spring and i'm contemplating it. Only thing is i wanna carry the misses over summer so actually want the heavier spring to stay in for that. so i'm trying to compromise with what i have to work with.
I got my settings on a spreadsheet at home but i've done the ratio to give me an idea so going by memory it is something like this:

Rear H/S compression - backed right off so 100% soft as a lot of people recommend
Rear L/S compression - 74 % towards soft
Rear Rebound - 75% towards soft (slow rebound... or more damping)
Front compression - 53 % towards soft
Front rebound - 67 % towards soft (slow rebound... or more damping)

So as you can see the front is closer to the factory setting of half way hard to soft, but more on the softer side. The rear is a bit softer than the front and seams to be compensating the harder rear spring.

It's still not ideal but close. I've also noticed i started softer and slowly been dialing it harder, this bike has 800km so still running in. I noticed a bit much nose dive this morning on the brakes so gonna dial the front compression a little harder and seemed a bit understeery exiting a corner so gonna turn the rear rebound a littler harder (quicker rebound) too. to see how that goes. Only quarter turn adjustments at a time.

jamjam

14th July 2010, 16:46

slofox

14th July 2010, 16:51

SVboy

20th July 2010, 15:09

Can I suggest getting the static and dynamic sags set before altering your various settings. Getting this small but important job done will give you an accurate and personalised suspension baseline from which to work from.

Pussy

20th July 2010, 17:26

jamjam

27th July 2010, 22:40

Oddly enough i've made a further tweak due to some instability entering corners now. i'm sure the suspension has been running in because it was shit on factory settings when i got it and now my settings are almost back to factory. It's done 1,100 kms.
The preload was set a while back, although i got two different readings depending on whether my mate did the measures or my girlfriend!!! i should really check it again.

But the front compression/rebound is pretty much on factory, except the rebound is 1/4 turn out further.
The back is 1/2 turn out on rebound, 1/4 turn out on H/S compression and 1.5 turns out on L/S compression from factory settings.

The handling feels pretty good with these settings so hopefully it's not gonna change any more from here. And i spent hours and hours scouring the internet for other peoples settings but so few people have posted their actual settings (in fact none had) so maybe this will help someone else in the future.

dipshit

28th July 2010, 09:10

And i spent hours and hours scouring the internet for other peoples settings but so few people have posted their actual settings (in fact none had) so maybe this will help someone else in the future.

If 10 people posted up their settings you would probably end up with 10 different configurations.

eg... Sport Rider's http://www.sportrider.com/suspension_settings/suspension/146_suggested_suspension_settings/suzuki.html recommended settings compared to another journalist's settings... http://www.motorcycle-usa.com/563/7395/Motorcycle-Article/Ben-Younger-Makes-Friends-with-the-Track.aspx on a K8 GSXR 750.

Sport Rider start with preload...! WTF... preload is set to the weight of the rider.

Front forks: Rebound, Low-s comp, Hi-s comp. (all numbers are turns out from full in)

Sport Rider: .25, 2.5, 3

Other journalist: 1, 1.5, 1

These are worlds apart considering 1/8 of a turn can make a noticeable difference.

I can't compare the rear shock settings because the numbers in Sport Rider are cut off by the add running down the side of the page in both of my web browsers. (can anybody else see them and post them up?)

Frankly I think recommended settings are a load of bullshit. There are too many other variables that will have influences on what someone will arrive at.

Odakyu-sen

28th July 2010, 09:29

[QUOTE=jamjam;1129810659]

gonna turn the rear rebound a littler harder (quicker rebound) too. to see how that goes. /QUOTE]

The factory rear spring is probably too heavy for a solo 75 kg rider. Think about it. The manufacturer will fit a spring that caters for the rider of average weight who may want to carry a pillion. The manufacturer will be banking on the common perception that "sports bikes have hard suspension" as well as the knowledge that bottoming out is worse that having a spring that is too firm.

Generally, if you back the rear shock's compression damping all the way off to zero and the rear feels a little better, then you are probably in need of a lighter rear spring. No amount of twiddling with the compression, preload or rebound settings will compensate for this basic problem.

The way I see it: the rear suspension preload is used solely to set your rear static sag -- say 10 mm. After that, you put your leathers on and sit on the bike. Hopefully, the rear end will go down about 25 mm when you sit on it. If it goes down much less, your spring may be too firm. If you were a 170-kg gorilla, and the rear end were to go down, say 40 mm, you would have a rear spring that wasn't firm enough for you.

The beauty of many after-market rear shocks is that you can swap their springs. You can physically alter the length of the shock, which is great for tuning the turn-in feel of the bike. (My old 900SS always seemed reluctant to track easily through fast sweepers until I undid the screw shank at the bottom linkage of the Ohlins and lenthened the shock by 5 mm. Completely transformed the cornering -- you could countersteer simply by "looking" where you wanted to go and the bike would do the rest. (Well, that's what it felt like.)

SVboy

28th July 2010, 10:23

+1 to the above threads-common sense ideas.

imdying

28th July 2010, 11:42

These are worlds apart considering 1/8 of a turn can make a noticeable difference.Interesting... we've been told on here a number of times by reputable people, that the adjusters make bugger all difference, especially small changes like those....

jamjam

28th July 2010, 12:50

Good comments. I agree that small turns do make a difference. i could feel the difference. One ride the bike is wallowing into corners with a bit of unpredictable tip in mid corner. I add half a turn rebound damping and 1/4 turn compression at the front then voila she's entering corners nicely.

I had similar experiences with the back aswell where it would feel vague and minor adjustments would fix it. I have documented in a spreadsheet and made about 6 or 7 changes (minor changes) over the last few weeks based on how the bike is feeling front and rear, entering/exiting a corner etc until i've narrowed it down to what i have set now and am pleased with it.

And yes the rear spring is too stiff for me but i want to carry the misses over summer so am working with it the best i can. Probably the only feeling i don't like about the back is it a little bit slippy feeling (particularly in wet) as i don't think it is comforming to the road at it's best but i am just wary of the throttle to compensate this. I've tried different configs and got it about the best i can at this stage. It has been worse with say too much rebound damping but it's good enough for me now to work with so is minor enough to not really be an issue.

dipshit

28th July 2010, 15:58

Interesting... we've been told on here a number of times by reputable people, that the adjusters make bugger all difference, especially small changes like those....

Depends. On my SV 1000 1/8 of a turn on the front compression made a noticeable difference. On my 600 I couldn't detect any difference on the rear rebound no matter how much I wound the rebound adjuster.

Robert Taylor

28th July 2010, 18:18

btw to save some confusion how i got the percentage figures it's like this...

Front compression.. max turns is 3.5... factory is 1.75 turned out counter clockwise from full in.
Therefore that is 50%.. if i was 2.25 turns out from full in then that is 64% towards soft. It just gives a nice visual of the relations between the front and rear settings.

You cannot relate it that way in percentage terms. The reality is that as the bypass needles get further withdrawn ( softer ) they are getting so far out of the bypass orifice that the latter stages have much less percentage impact on damping force change. As you get further and further in a incremental change in position ( say 1/8th of a turn ) has a much much greater percentage change than if it is a long way out.
It is not linear.

Robert Taylor

28th July 2010, 18:23

If 10 people posted up their settings you would probably end up with 10 different configurations.

eg... Sport Rider's http://www.sportrider.com/suspension_settings/suspension/146_suggested_suspension_settings/suzuki.html recommended settings compared to another journalist's settings... http://www.motorcycle-usa.com/563/7395/Motorcycle-Article/Ben-Younger-Makes-Friends-with-the-Track.aspx on a K8 GSXR 750.

Sport Rider start with preload...! WTF... preload is set to the weight of the rider.

Front forks: Rebound, Low-s comp, Hi-s comp. (all numbers are turns out from full in)

Sport Rider: .25, 2.5, 3

Other journalist: 1, 1.5, 1

These are worlds apart considering 1/8 of a turn can make a noticeable difference.

I can't compare the rear shock settings because the numbers in Sport Rider are cut off by the add running down the side of the page in both of my web browsers. (can anybody else see them and post them up?)

Frankly I think recommended settings are a load of bullshit. There are too many other variables that will have influences on what someone will arrive at.

Of course what also needs to be taken into account is that first world countries such as North America and the main European economies will have a much higher percentage of relatively smooth roads. Roads that dont challenge the suspension like our ''goat tracks'' here in the shaky isles. So internet posted settings and overseas mag settings should not be treated as gospel.

Robert Taylor

28th July 2010, 18:53

With GSXR600 / 750 we have now modified in excess of 30 sets of forks because they severely lack high speed rebound control. The effect of that is that when you have gone deep into a corner and have used all the travel up the bike tries to ''stand up'' all too readily as you release the brakes. That causes a little bit of instability and makes the bike understeer off especially the tightest turns.
People try and ''tune'' this out by moving the rebound clickers in further and further and it kind of fudges it but then introduces another problem. That rebound adjuster moves a needle in the bottom of the cartridge rod which affects flow not only in extension ( rebound ) but also in compression. By having that adjuster in so far it gives a little more high speed rebound ( but actually not enough ) but also gives too much low speed rebound and too much low speed compression.
So at the top of the stroke as its extending ( accelerating off corners ) the forks are very lethargic in action and that harms their responsiveness to suface irregularities both on the upramps of same and downramps. that affects the grip your tyre has with the road surface! if the low speed rebound is too lethargic it is ''slowing down'' / impeding the ability of the fork springs to put as much pressure as possible on the tyre. Loss of grip.
Moreover, if the adjusters end up in a crazy place the damping can cavitate. The working range of these adjusters that gives you good response but doesnt also overdamp at low shaft speeds is actually a lot narrower than people think. They are not a magic fix all and dont compensate for any internal valving deficiencies, that account for 90% or more of mass flow.
If you are going to end up doing track days on this bike it is essential to get those forks sorted and to also disarm 80% of the hydraulic bottom outs in them, this being a great way to crash if not done, or at least increase the chances markedly.
With respect to the rear the high speed compression adjuster can often be counterintuitive, especially if you are using it as a tuning tool when the fitted main spring rate is correct ( not too stiff as it is now ) Sometimes a very soft preload setting on that high speed adjuster can make the bike feel too stiff over bumps. It acts like a preloadable dump valve when you ride over an abrupt bump. If it dumps too much oil too quickly it allows the chassis to ''blow through its stroke too readily and too quickly. That causes it to get deeper into the rising rate curve of the linkage, the deeper in it gets the faster and further the shock shaft moves for any given distance of wheel movement. The faster you move that shock shaft the greater the damping force created. Relate that to a humble door closing damper........move the door only slowly and resistance is only light, try and move it faster and it almost locks up in your hands.
Stiffer can often be softer!!!
On models with ridiculously progressive links ( Ducati 848 thru 1198, 09 Yamaha R1 and Triumph 675 series ) the trick with suspension is to keep it high in its stroke to do all its best work and to keep it ''way from the link'' as much as possible.
Although its oversimplistic think of it all in these terms: springs are roughly about position, damping is about controlling rate of change of position.
E-mail me your e-mail address and Ill transmit to you a complimentary set up tips manual. I can also forward you a price to upspec those forks, its actually very affordable. Talk to Dipshit and Pussy about it also, they have had it done.

Odakyu-sen

28th July 2010, 21:58

And yes the rear spring is too stiff for me but i want to carry the misses over summer so am working with it the best i can.

I am fortunate that I never carry a pillion on my R6 so I can run a light 7.0 N/mm spring which is about as soft as I can get away with. Wonderfully complient on NZ roads, but would be too light to handle a pilllion.

(I don't do track days and I don't go fast on roads I don't know, so bottoming out has not been a problem for me.)