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Discussion Starter · #1 ·
Ok I keep learning more about our fun little 3 cylinder screamers.

I just got off the phone with Dan at Traxxion Dynamics. I have been having a rear suspension harshness problem after installing my ZX6-RR shock.

Since they recently did a suspension overhaul for one of the guys on this forum they now have good numbers for the FZ-09 on what needs to be done. Unfortunately they first did my shock overhaul a couple of weeks prior to this.

The man culprit is the very progressive design of the rear suspension linkage. As the suspension compresses the movement of the shock compresses exponentially. So if you push down on the seat the seat moves down fairly smoothly for a bit then its like it hits a wall. This is due to the linkage ramping up quickly at that point. This can make for a harsh ride when you hit a square edged bump. For me it felt like my tail bone was going to end up between my shoulder blades.

The fix or mitigation of this is to revalve the shock to significantly reduce the compression damping. So I just shipped the shock back to Traxxion for them to work their revalve magic on it.

By the way the customer service at Traxxion is second to none. Dan is a great guy and will spend plenty of time with you on the phone and email to make sure you are happy.

Wheelie on boys!
 

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You may be misunderstanding Dan.

There are 2 different compression damping channels/routes/circuits on most good shocks.

There is the low speed compression damping circuit that is for the suspension movement as you go through turns, regardless of your forward speed. This is called low speed compression damping because the shock compresses at a relatively slow rate as it moves to handle this type of suspension load.

Then there is high speed compression damping circuit that is for suspension movement to absorb a pot hole or other sharp edged bump. This is called high speed compression damping because the shock compresses very quickly (5-10X or more quickly than in low speed compression) as the shock tries to absorb the pot hole.

Each of the high and low speed circuits have separate valves that can be adjusted separately.

Some shocks (most OEM) do not have separate high and low speed circuits - maybe that is the case for the ZX6 shock. I don't know. If that is the case, then you only have one compression valve to work with instead of two separate valves and your only choice is to modify the low speed compression damping valve to be more reactive to high speed compression situations but this usually also reduces the low speed compression damping function to some degree.

It is a compromised design requiring a compromised valving.

My "double-clicker" Penske shock has separate high and low speed compression damping circuits, each having their own separate valves. Only the low speed compression damping is adjustable from outside the shock. If I wanted different high speed compression damping I would have to send it to Traxxion or Penske to have the high speed valve changed. But they could change the high speed valving without affecting the low speed valving.

The second "clicker" on my shock is for the low speed rebound damping adjuster.

If you have a "tripler-clicker" shock then the high speed compression damping has a external adjuster.
 

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Motomania, that's all inside the shock. But not all bikes have the same linkage characteristics, seems the 09 is further from linear than most.
 

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That make sense. My bump adjuster on my XZ-10 shock are all the way open wit the 9.7 kg/mm spring. The stiffer spring (from 9.1) gave me more initial support and less damping kind of make things a bit smoother over bumps.
 

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Discussion Starter · #5 · (Edited)
You may be misunderstanding Dan.

There are 2 different compression damping channels/routes/circuits on most good shocks.

There is the low speed compression damping circuit that is for the suspension movement as you go through turns, regardless of your forward speed. This is called low speed compression damping because the shock compresses at a relatively slow rate as it moves to handle this type of suspension load.

Then there is high speed compression damping circuit that is for suspension movement to absorb a pot hole or other sharp edged bump. This is called high speed compression damping because the shock compresses very quickly (5-10X or more quickly than in low speed compression) as the shock tries to absorb the pot hole.

Each of the high and low speed circuits have separate valves that can be adjusted separately.

Some shocks (most OEM) do not have separate high and low speed circuits - maybe that is the case for the ZX6 shock. I don't know. If that is the case, then you only have one compression valve to work with instead of two separate valves and your only choice is to modify the low speed compression damping valve to be more reactive to high speed compression situations but this usually also reduces the low speed compression damping function to some degree.

It is a compromised design requiring a compromised valving.

My "double-clicker" Penske shock has separate high and low speed compression damping circuits, each having their own separate valves. Only the low speed compression damping is adjustable from outside the shock. If I wanted different high speed compression damping I would have to send it to Traxxion or Penske to have the high speed valve changed. But they could change the high speed valving without affecting the low speed valving.

The second "clicker" on my shock is for the low speed rebound damping adjuster.

If you have a "tripler-clicker" shock then the high speed compression damping has a external adjuster.
V2 Bob is correct when he says " Motomania, that's all inside the shock. But not all bikes have the same linkage characteristics, seems the 09 is further from linear than most."

I will add: The linkage we speak of is the aluminum part that the end of the shock bolts to. As the rear wheel travels upward the link does not travel in a linear fashion. As the linkage moves it compresses the shock. Slowly at first then more rapidly as the suspension compresses further. This further in the stroke compression is what adds to the harshness of the ride. The way to compensate for this is to reduce the high speed compression damping in the shock. This is what Traxxion is planning to do to my shock. This is done by changing the shim stack to allow an easier flow of oil through the shock when compressed.

I hope this clears up the corn fusion.
 

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V2 Bob is correct when he says " Motomania, that's all inside the shock. But not all bikes have the same linkage characteristics, seems the 09 is further from linear than most."

I will add: The linkage we speak of is the aluminum part that the end of the shock bolts to. As the rear wheel travels upward the link does not travel in a linear fashion. As the linkage moves it compresses the shock. Slowly at first then more rapidly as the suspension compresses further. This further in the stroke compression is what adds to the harshness of the ride. The way to compensate for this is to reduce the high speed compression damping in the shock. This is what Traxxion is planning to do to my shock. This is done by changing the shim stack to allow an easier flow of oil through the shock when compressed.

I hope this clears up the corn fusion.
I understand the link is a progressive push/compression of the shock, that is true for almost all link type suspensions. Apparently, the FZ09 is more progressive than some others. I get that as well.

I am curious what the progressive curve looks like... Maybe Dan can provide that and some comparisons to some other bikes, just for curiosity purposes.

The high speed compression damping valve inside the shock is still the culprit because it does not match the link's progressive curve.

So the solution is to adjust the high speed compression valving as Traxxion is suggesting. That is good.

Hopefully that means the ZX6 shock has separate high and low speed valves.

When I read your first post it did not seem like you were aware there are 2 compression and 2 rebound damping circuits in "better" shocks and that is a large part of why those shocks are better.

Good to know you are aware of that.
 
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I will say this, mine was the donor bike the tore into and the thing rides on rails. I was up in the mountains of north GA this weekend having a blast on it. Was leaned over in a fast sweeper @ blood mountain and hit a good bump mid corner. Handled it like a boss and kept on rolling. Now alls I can think about is jumping on the bike for another run. Good stuff they do.
 

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I will say this, mine was the donor bike the tore into and the thing rides on rails. I was up in the mountains of north GA this weekend having a blast on it. Was leaned over in a fast sweeper @ blood mountain and hit a good bump mid corner. Handled it like a boss and kept on rolling. Now alls I can think about is jumping on the bike for another run. Good stuff they do.
Uphill left turn with a big dip in it? Yep...I know about that one.
 

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Could an expert on the zx6rr shock jump in here and give us some insight into the settings??

Several people have said the zx6rr shock has both hi and low speed settings...

Any input would be great!
 

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Could an expert on the zx6rr shock jump in here and give us some insight into the settings??

Several people have said the zx6rr shock has both hi and low speed settings...

Any input would be great!
If you are not sure where to start... start full soft and work from there. Safer to start soft than the other way around

Sent from my SAMSUNG-SGH-I337 using Tapatalk
 

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Yes, I agree with marthy, start soft, adjust up. I was always taught to tighten when you override the current settings.
 

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Discussion Starter · #14 ·
I will say this, mine was the donor bike the tore into and the thing rides on rails. I was up in the mountains of north GA this weekend having a blast on it. Was leaned over in a fast sweeper @ blood mountain and hit a good bump mid corner. Handled it like a boss and kept on rolling. Now alls I can think about is jumping on the bike for another run. Good stuff they do.
Fantastic! I am envious.

If they were not on the other side of the country I would have loaned them my bike in a heartbeat.

You are a lucky man. I would venture a guess that they did both ends of your bike for what it would cost most of us to do just one end!

Some times there are just not enough rocks according to Forest Gump.
 
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