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I've got family up the coast- my brother in law and sister in law had to get their row boat out and row up the street (with their 4 yr old and 5 week old) to get out. They rowed a couple of streets to meet my mother in law to stay with them until it subsides.

I have learnt more about suspension on MT09s than i have with the rest of my bikes- including swapping forks from say, a K4 gsxr 1000 to an 88 model gsxr 1100. An MT09 with sorted suspension is worth the effort.
 

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Some suspension "experts" use track focussed spring rates, that is wrong for street use, unless your streets are like race tracks. Check your static and rider sag figures, rear should be 35 - 38mm rider sag. 10 - 13mm static sag. This will show if the spring rate is OK or not.
Then you can initially set damping with the bounce test. (See the Dave Moss vids)
Then fine tune them on the road.
Likewise with the front 40 - 45mm rider sag, 25 - 30mm static.
 
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I've already offered for him to come to my place to check sag once we dry out.
A new bridge was built last year at Windsor that was flood proof, 4.3m (a bit over 14 feet) clearance. It's completely flooded. I reckon it'll be a week or 2.
 

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You poor buggers in Oz, it's either drought or floods, no middle way. But at least you have a summer longer than a month.
 

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Discussion Starter · #27 ·
Some suspension "experts" use track focussed spring rates, that is wrong for street use, unless your streets are like race tracks. Check your static and rider sag figures, rear should be 35 - 38mm rider sag. 10 - 13mm static sag. This will show if the spring rate is OK or not.
Then you can initially set damping with the bounce test. (See the Dave Moss vids)
Then fine tune them on the road.
Likewise with the front 40 - 45mm rider sag, 25 - 30mm static.
Just on talking pre-load, the specifications from Matris say that preload should be 12mm (-2 / +4). I'm unsure if this is for the sag, or if it's the suggested starting point for the shock rings thread...
 

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It's installed preload, 12mm from when the lock rings touch the spring. My Nitron is the same.
 
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Discussion Starter · #29 ·
Did some road testing this weekend, with some grease on the shock rod to measure travel. Here are my findings:

No matter if I'm on fully hard or fully soft rebound/compression clicks, I feel many bumps at both low speed and high speed.
I do seem to use most (3/4s?) of my suspension travel with the clicker on a soft setting. It's as if the spring gives that much 'give' then comes to a hard stop.
If I pin the throttle, the back will squat and use pretty much ALL of the travel (more so than any impacts from bumps!?)
I rode around with my girlfriend (65kg + gear) on the back - the ride felt more compliant, the little bumps were much less
I tried to ride around with the full hard rebound/compression setting, but after a few hundred metres on a bumpy road, I thought "ok that's enough I proved the point" as it was so jarring, like those 1900s hardtail motorbikes! It didn't use full travel, however

Essentially, it feels like there is low speed dampening i.e. when I accelerate, and when there's a dip in the road, BUT, there is zero dampening for high speed, quick impacts

From what I see, everyone reports the forks to be undersprung on the XSR. However, I am on very light preload and the softest setting for rebound/compression, and the forks barely use 2/3 travel, only pushing a little further with a big emergency stop. Might pull the caps off and see if the top of the spring is marked with a rate.
Unfortunately, I couldn't see a marking on my shock spring and I don't have a jig to suspend the frame to get the shock out. I also don't want to touch it in case the shop is prepared to exchange it etc, so I want to avoid scratches and marks

I'm aware this thread is turning into a bit of a dear diary structure, but I'm hoping that others that are trouble shooting or learning about suspension settings can follow the same steps that I'm going through and have a better understanding. I won't be able to speak to the shop anytime soon (It's Easter long weekend here and I'm moving house soon) but I'll definitely update after that - especially if a new spring sorts my concerns.
 

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I'm aware this thread is turning into a bit of a dear diary structure, but I'm hoping that others that are trouble shooting or learning about suspension settings can follow the same steps that I'm going through and have a better understanding. I won't be able to speak to the shop anytime soon (It's Easter long weekend here and I'm moving house soon) but I'll definitely update after that - especially if a new spring sorts my concerns.
Don't worry about that, we're all here because we love bikes and have an interest in them, if not, we wouldn't be on a motorbike forum :)
 

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Could you give us your sag figures? front and rear, rider and static. And what preload you have added.
Keep in mind that damping does not affect suspension travel, just the speed at which that travel is used.
 
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You seem to have diagnosed your shock issue without knowing it.
If the bike felt more compliant with +65kg on it, then it's obviously oversprung. My standard shock was lovely with the wife on the back, but butt jarring solo.
Until you get the right spring on it, you are just chasing your tail as it will NEVER be right!
 

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Having said the above, damping does affect sag numbers. Set sag at some mid point damping setting
 

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Discussion Starter · #34 ·
Could you give us your sag figures? front and rear, rider and static. And what preload you have added.
Keep in mind that damping does not affect suspension travel, just the speed at which that travel is used.
Had my brother come over tonight, so I could get a somewhat reliable sag figure. Here's what we got:
Forks (measuring the fork tube)
Static = 141mm, rider = 98mm
141 - 98 = 43mm or 31%
Official fork travel is 137mm

Shock (measuring from the swing-arm above the axle nut to a reference point on the seat above the subframe more or less directly above the axle
Static = 593mm, rider = 559mm
595 - 559 = 34mm or 26%
Official shock travel is 130mm, unsure if this is reduced in the Matris. It's bloody hard to get technical specifications from this particular Italian brand

Bear in mind, these are the settings performed by the shop AFTER I returned complaining of the shock being too stiff. Hopefully these numbers rule out "this guy is an idiot and had his preload wound out to max settings" (which you can never immediately rule out on the internet!!)
 

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My last post on this subject.
You cannot 'soften' a spring. That's why most of them have a recorded rate on them. They absorb energy in a controlled, measured manner, then rebound to their original state.
All preload does is alter ride height, so if you park a top box/pillion on the bike, you can maintain the geometry of the bike, or play around a bit to alter the steering characteristics.
An overly stiff spring (for your weight) will need very little or no preload adjustment to maintain geometry, as you do not put enough force into it for it to work properly but will ride like a gun carriage over cobbles.
Taking a wild stab, but I guess that all the shop did was to back off the preload and compression damping.
Until you KNOW you have the correct spring, you're just dicking around the problem
 

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Had my brother come over tonight, so I could get a somewhat reliable sag figure. Here's what we got:
Forks (measuring the fork tube)
Static = 141mm, rider = 98mm
141 - 98 = 43mm or 31%
Official fork travel is 137mm

Shock (measuring from the swing-arm above the axle nut to a reference point on the seat above the subframe more or less directly above the axle
Static = 593mm, rider = 559mm
595 - 559 = 34mm or 26%
Official shock travel is 130mm, unsure if this is reduced in the Matris. It's bloody hard to get technical specifications from this particular Italian brand

Bear in mind, these are the settings performed by the shop AFTER I returned complaining of the shock being too stiff. Hopefully these numbers rule out "this guy is an idiot and had his preload wound out to max settings" (which you can never immediately rule out on the internet!!)
That's almost exactly what I have except for 3mm more rider sag at the rear. So I'd say the spring rates are good. I'd now look at damping settings. Have a look at the way Dave Moss does the bounce test. that'll get you close and you can fine tune on the road.
 

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Discussion Starter · #37 ·
That's almost exactly what I have except for 3mm more rider sag at the rear. So I'd say the spring rates are good. I'd now look at damping settings. Have a look at the way Dave Moss does the bounce test. that'll get you close and you can fine tune on the road.
Because I can get the preload within spec, does that rule out a softer spring being more suitable?
I've set the rebound/compression damping to 0 on this shock and I still felt every bump.
I feel it is more likely that the spring isn't giving enough than the shock is resisting on those bumps
 

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My last post on this subject.
You cannot 'soften' a spring. That's why most of them have a recorded rate on them. They absorb energy in a controlled, measured manner, then rebound to their original state.
All preload does is alter ride height, so if you park a top box/pillion on the bike, you can maintain the geometry of the bike, or play around a bit to alter the steering characteristics.
An overly stiff spring (for your weight) will need very little or no preload adjustment to maintain geometry, as you do not put enough force into it for it to work properly but will ride like a gun carriage over cobbles.
Taking a wild stab, but I guess that all the shop did was to back off the preload and compression damping.
Until you KNOW you have the correct spring, you're just dicking around the problem
This post is a perfect description. A great explanation for a common misconception. There are people everywhere that will argue to the death that you can adjust a too soft or too harsh spring to make a bike work correctly. Not True. This post is the exact truth.

As I said perviously, In looking at the Matris website that these look like a decent shock. You're not going to adjust that shock to work with the wrong springs but it doesn't mean that it's a bad shock. They make different spring rates and odds are with the correct spring and no adjustment at all, they will feel 100% better than now. Then set the sag, set rebound and compression to their lightest settings and then ride for a while. I have a local farm road that is a total mess of bad pavement and frost heaves that I use to set up suspension. Just do front or rear, not both together. I start with rebound only and adjust 4 clicks at a time until I can notice a difference. When I finally feel like it's good then I move on to compression and work through the same process. When it's right, the bike goes from a bucking bronco to feeling like your just skimming above the road. Every time I've gotten it to work on that road, it just works in the turns. My local suspension guy told me to work it like this and you can figure this out as I did. Once you break it down like that, you stop worrying about screwing it up. If you have to put everything back to zero and do it over, no big deal. The hardest thing for me to figure out is which end is bad. When the forks were bad it made the rear feel bad. I still am not fully understanding how rebound affects the feel of the bike. I understand the theory but I'm not at the point of knowing in real riding situations. I'm still learning but it's part of what makes motorcycles fun.
 

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Because I can get the preload within spec, does that rule out a softer spring being more suitable?
I've set the rebound/compression damping to 0 on this shock and I still felt every bump.
I feel it is more likely that the spring isn't giving enough than the shock is resisting on those bumps
You can fit whatever you like, but a softer spring will use more travel, possibly hit the bump stop (especially two up) and will alter steering geometry. It's lucky that the 09 has so much suspension travel or it'd be much worse.
The problem is that the 09 is a very light bike and the sprung/unsprung weight ratio is much less than on heavier bikes that have more compliance. It's the first thing I noticed going from a plush Ohlins equipped Bandit to the 09.
I've just got used to the bike, but I had to fix high speed comp damping in the forks because that was really beating me up.
 
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Discussion Starter · #40 ·
Just wondering - the forks are super stiff on my bike (will be changing to a lighter fork oil soon)
Could the harshness and lack of give on the forks push the weight onto the rear shock before it hits the bump, causing or at least contributing to the poor travel?

No real updates from my end, I haven't received a call from the shop and I haven't called out just yet, still moving house taking priority
 
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