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Offline Cazzy_R

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Re: Fully adjustable Wilbers shock.
Reply #120 on: October 18, 2019, 02:37:34 PM
 Weird.
 The less rear rider sag you have, the higher the ride height will be and the quicker the steering should be.
 Did you increase fork pre-load thus raising the front at some time during spring swaps?
 Tyre pressures okay?

 I assume the Wilbers shock is the same length as stock?
 Is the length adjustment just plus stock or plus/minus stock length?

 
Cazzy_R

Tighten it 'til it strips then back it off half a turn.

Offline RobZ900

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Re: Fully adjustable Wilbers shock.
Reply #121 on: October 18, 2019, 03:23:18 PM
*Originally Posted by Cazzy_R [+]
Weird.
 The less rear rider sag you have, the higher the ride height will be and the quicker the steering should be.
 Did you increase fork pre-load thus raising the front at some time during spring swaps?
 Tyre pressures okay?

 I assume the Wilbers shock is the same length as stock?
 Is the length adjustment just plus stock or plus/minus stock length?

Havent touched the forks since starting the whole shock saga, tyre pressures are fine, yes the shock is the same length as stock.

Dont misunderstand what I meant in my previous comment. I adjusted the preload on the spring and measured the preload by measuring the length of the spring. Based on my assumption of the spring having 185mm free length, I thought I had 18mm of preload wound in as the length was 167mm, but because the spring was only 180mm, not 185mm, I only had 13mm of preload on the spring, but the adjustment collars were at the point that it should have been 18mm of preload if that makes sense. With the new spring being a true 185mm free length, Ive got 8mm if preload wound in, so in theory it should be sat higher in the stroke and thus turn quicker, but I wont know til I take it out for a spin.

As for the height adjuster, it goes +/- 5mm.
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Offline JohnCW

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Re: Fully adjustable Wilbers shock.
Reply #122 on: October 18, 2019, 10:38:24 PM
*Originally Posted by RobZ900 [+]

The only thing Im concerned with now is the speed of the steering. I think it was you John, that said too much rebound damping can slow the steering down, requiring more effort to muscle the bike into corners. I experienced that feeling 2 days ago when I took the bike to the suspension shop with the 120 spring fitted. The feeling of the steering response compared to having the 110 spring fitted was heavier. Obviously thats going to be down to the heavier spring rather than the rebound settings, so with the spring now being another step up from the  120, Im curious of the effect on the steering response. The only thing I can think of to counteract it is the height adjustment. I know that raising the back a couple of mm generally speeds the steering up, so Im curious if raising the back will counteract the heavy steering that comes with the the heavier spring. Whatever the case is, its going to be fun getting it all dialled in to my preference :028:

I wouldn't go changing ride height at this stage.  That's super 'fine tuning' stuff best left to the very last.

Either excessive rebound or slow speed compression damping will create that heavy steering feeling.  Not hard to imagine why.  Just think of the suspension trying to move, either direction, in treacle.   

To assist in getting damping settings in the ballpark, perhaps start with a few assumptions.  With the new race orientated shock assume as supplied for the road,  the rebound will be WAY to slow, and both the slow and fast speed compression also to slow.  Hence that heavy steering feeling. 

So as a starting point I suggest opening up the rebound several clicks, and the same for both the slow and fast compression damping.    Then test ride, and I'm pretty confident that heavy steering should have disappeared.  Don't worry the ride quality is a bit flakey at this point, the objective is open out both the rebound and compression beyond that heavy sticky feeling.

Once the nice loose feeling of the bike has been reestablished, then progressively bring the rebound back up till the heavy feeling reappears, back off one click.  A heavy feeling from excessive rebound is sort of a 'constipated' feeling.  Excessive compression is far more 'in your face' heavy.  With the compression damping still wide open at this point the ride quality may be quite poor.

Now bring up both the slow and fast compression damping till the ride quality improves, go too far and that heavy steering feeling will come back.

Then finally fine tune the fast compression damping based on how it feels when you hit a big square edge pothole. 

P.S. It might be hard to imaging why inadequate compression damping creates a harsh ride (just like excessive will).  Trust me it does.  My guess as to why is the returning suspension with a desirable fast rebound slightly compresses the tire.  This wants to push the suspension back up again.  Without adequate compression damping to control this the suspension 'chatters' up/down giving a harsh feeling.
Last Edit: October 18, 2019, 10:47:58 PM by JohnCW

Offline RobZ900

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Re: Fully adjustable Wilbers shock.
Reply #123 on: October 18, 2019, 10:59:12 PM
As always John, thanks for the input. Going to get the sag numbers dialled in and then will give the above a try when Im up to it. When I first got the shock with the 110N/mm spring, I did initially back off all 3 damping adjusters by 2 clicks each as it just felt a bit harsh. That seemed to soften things up a bit, but obviously Ive now increased the spring rate to suit my weight, Im getting more of a feel for how the damping is effecting the ride. I did read on the K-Tech Razor R thread that Greyhairhoon ended up backing his rebound out to 20 clicks and compression to 18 to get it to feel more compliant. Granted its a different shock, but goes to show that some big changes can be needed I suppose.
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Offline JohnCW

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Re: Fully adjustable Wilbers shock.
Reply #124 on: October 19, 2019, 12:49:42 PM
*Originally Posted by RobZ900 [+]
As always John, thanks for the input. Going to get the sag numbers dialled in and then will give the above a try when Im up to it. When I first got the shock with the 110N/mm spring, I did initially back off all 3 damping adjusters by 2 clicks each as it just felt a bit harsh. That seemed to soften things up a bit, but obviously Ive now increased the spring rate to suit my weight, Im getting more of a feel for how the damping is effecting the ride. I did read on the K-Tech Razor R thread that Greyhairhoon ended up backing his rebound out to 20 clicks and compression to 18 to get it to feel more compliant. Granted its a different shock, but goes to show that some big changes can be needed I suppose.

If I can stressing one point, which took me years to discover, with a correctly set (relatively fast) rebound damping a loose slow speed compression damping can give a harsh ride.  It's hard to believe this harsh ride often needs to be addressed by tightening up the slow speed compression damping, rather than our natural inclination to keep winding it out, thinking less will mean softer. 


Offline RobZ900

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Re: Fully adjustable Wilbers shock.
Reply #125 on: October 19, 2019, 10:05:04 PM
Well there was always going to be a compromise somewhere, and tonight Ive found it. Sag is now set to where it will be staying. Still not where I would have liked have got to, but Im not willing to go up another spring rate. When the 130N/mm was fitted, my suspension guy wound in 8mm of preload. Ive increased that to 11mm which has given me 44mm of rider sag and 8mm of static. I did get the rider sag down to 41mm, but that only left 5mm static and I thought it would be better to have a bit more. I dont think it would be worth going up again for the extra 3mm of travel.

Also bounced on the suspension as best I could with all my gear on to see how far down the travel Im getting. With this spring, Im 35mm away from bottoming out, rather than the 17mm with the previous spring.

One thing that will work in my favour is that Ive been off work for a month and Ive been on a course of steroids, so Ive gained about 5lbs, so once I get back to work, I should trim that back off which will help the sag. Still not as happy as I was hoping to be, but I guess it is what it is. Time to move on to getting the damping set!
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Offline JohnCW

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Re: Fully adjustable Wilbers shock.
Reply #126 on: November 03, 2019, 06:20:51 AM
Hi Rob,
How's progress going?

John

Offline RobZ900

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Re: Fully adjustable Wilbers shock.
Reply #127 on: November 03, 2019, 09:16:03 AM
*Originally Posted by JohnCW [+]
Hi Rob,
How's progress going?

John

Hey john, in all honesty I havent been able to get out on the bike since setting the rebound and compression damping, body just hasnt been up to it. Currently on another course of steroids and waiting to have my tonsils out so they can do a biopsy on them to confirm what they think Ive got. After all of this they should be able to give me ongoing medication so hopefully none of this should happen again and all will be good.
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Offline JohnCW

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Re: Fully adjustable Wilbers shock.
Reply #128 on: November 03, 2019, 12:17:00 PM
*Originally Posted by RobZ900 [+]
Hey john, in all honesty I havent been able to get out on the bike since setting the rebound and compression damping, body just hasnt been up to it. Currently on another course of steroids and waiting to have my tonsils out so they can do a biopsy on them to confirm what they think Ive got. After all of this they should be able to give me ongoing medication so hopefully none of this should happen again and all will be good.

Sorry to hear that.  Take care.

John

Offline RobZ900

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Re: Fully adjustable Wilbers shock.
Reply #129 on: November 03, 2019, 02:11:23 PM
*Originally Posted by JohnCW [+]
Sorry to hear that.  Take care.

John

No worries, on the right track now so should start improving. Theyre pretty sure they know what the problem is, just want to do a biopsy to confirm. Once thats done, they can sort out medication to stop it from happening again.
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