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guzzler

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G'day folk's

I've just had the greenies forks serviced with those pesky bypass holes blocked/ revalved and resprung with .95 straight rate springs.I weigh 90 kg's.

Gotta say, it's a bloody huge improvement over the way it was and I'm quite chuffed.

However, as the forks and shock had to be removed to be sent to the suspension specialist then re-installed, I'm just trying to figure out the settings and get a base if I want to adjust further!

It's bloody confusing (why ??) but from what I can fathom Compression has 16 clicks of adjustment and Rebound has 18 clicks.

As they are set now compression is 8 x clicks out from full in ( midway? ) and Rebound is 12 clicks out from full in. ( bit more than halfway?)

This is as they came back to me.

My question is when the screw is full in, is this negative (or soft/less damping) and screw wound full out positive (or harder/more damping)?

I never touched the suspension from when I last had it done.

I have to say that this new bloke has done a far better job....

Cheers Guzzler 

 

 

 

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 Turn in = Increase Damping ("stiffer", so to speak).

Also, consider that the clicks are likely not linear, as in half the clicks sets the damping at halfway. More likely half clicks in  = 3/4 damping.

Peter Verdone comments on this and shows a graph about halfway down on this page:

http://www.peterverdone.com/archive/lowspeed.htm

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What docc said, clockwise / turned in is more dampening. More dampening is slowing down movement of the fork in that direction, so the compression adjuster turned all the way in would be maximum compression dampening and the slowest compression of the fork it can do. The rebound adjuster turned all the way in would be maximum rebound dampening, meaning the rebound of the forks would be as slow as possible. Normally the reference point is the adjuster screwed all the way in as that is a positive stop where the needle hits the seat. When you turn the adjuster out, counter-clockwise, there is often not a positive stop as the needle is simply moving away from the seat. So where it stops is not always identical on one unit to another. It should be, but maybe it isn't. But turned all the way in, all the way clockwise, will always be the same because in that direction it stops when the needle hits the seat.

Usually on the street you want as little dampening as you need to control suspension motion. At least that is my take. But if I paid someone who knows more than I do to re-valve the forks I would start with the adjusters where ever they put them. I would turn them all the way in, counting how many clicks out they are, and then put them back to that. From there I would adjust them in or out as required for best results. You could then use that info to have further adjustments made to the valving. If you had to turn the compression adjuster in to get the desired ride quality that would mean the valving maybe needs to be a little firmer, for example.

@LaGrasta, just so you know, without blocking off the bypass holes as @guzzlersaid he had done you may find the adjuster has very little impact on compression dampening except in the last inch or so of travel (when the piston has gone by the bypass holes). By blocking off the bypass holes you force more oil to pass through either the valving in the piston or the adjuster. Without blocking off the bypass holes the fork oil is pretty much free to bypass the valving and the adjuster until the piston goes past the bypass holes, which is in about the last inch of suspension travel. The forks can work much better with one or more of those bypass holes blocked off. This seems to be mainly the earlier 40mm forks. I don't think the later 43mm forks have the same issue. But it is hard to say for sure, as has been mentioned you never know which parts are on a given Guzzi. 

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Thanks fella's

It's kinda hard to know which way is up as no bloody markings on the screws or whatever so no indication other than looking at the screw being above or below the nut!

On my compression side the screw is @ 8 clicks or halfway (of16) and screw is about flush with the top...

The Rebound is 12 clicks (of 18) from full in and just below the nut.

So, I'm assuming Comp is middle of the road and Rebound is approx 3 x clicks from middle of the road..

But the gist of it is screw wound in (below /the nut) is + and more damping whilst screw wound out (above the nut) is - and less damping ?

Really appreciate your input!

As I mentioned though this is how they came back to me and the difference between old and new is quite incredible, much more FEEL from the front very little dive either and just bloody composed! I think Peter has also backed off the preload of the shock when he serviced it as well and front and back feel more in tune with each other now.

As it was the Hyperpro 460 shock had a lot of preload and back end probably too Hard whilst the progressive springs and no compression damping in front meant it was too soft! Add in the fact that the suspension was 45,000 kays old and overdue a service...

It's no wonder it feels BETTER ha ha, but it is seriously good now!

Rapt

Cheers Guzzler

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Amazing how these V11 respond to suspension tuning. So glad to hear it's much improved!

Again, have a look at Verdone's description and graph of damping adjustment. You will see why setting the "clicks" halfway sets the damping at 75%. He also explains why the settings are more "sensitive" at the closed (most damping) end and least effect at the opposite end of the adjustability.

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@GuzziMoto thank you. I wish I knew about blocking the bypass holes when I had these apart, replacing the seals. Due to a continued seal leak, I still have the right fork apart, would only blocking this side help or hinder?

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27 minutes ago, LaGrasta said:

@GuzziMoto thank you. I wish I knew about blocking the bypass holes when I had these apart, replacing the seals. Due to a continued seal leak, I still have the right fork apart, would only blocking this side help or hinder?

G'day mate 

It's the Compression or left side one that needs it...

Cheers Guzzler

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  • 3 weeks later...

G'day folk's

Just a wee update.

I've figured out that when the forks were re-installed on the bike, Peter ( the suspension guru ) had set them in the middle of the adjustment range, not for any particular reason but mid-way and for me to adjust as I see fit!

So, to that end I've been fiddling around and working things out...

Although even with the damping set in the middle it's better than it was but I'm beginning to find that on anything less than a billiard table racetrack LESS Damping is better!

I was able to get out for a 300k ride last weekend with Comp on +4 clicks and Rebound on +6 .This is better again on the goat tracks we call roads down here but feel like it could be tweaked a bit more.I've now got them set at Comp +2 / Reb +4 in readiness for another wee jaunt tomorrow to see how that goes!

I reckon I may end up with this setting?

Gotta say though, what an improvement over the way she was....

GuzziMoto, many thanks mate not only for identifying the issue in the first place finding the solution then when done guiding this clown through setting the forks up...

I'm very close to getting her set-up just so...Chuffed.

Cheers Guzzler    

  

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My methodology for setting street suspension is this; 
1st, set ride height and sag. I like 1/2" front and 1/2-1" rear. Front is difficult to change, so 1/2" to 1" is ok. Spring rate is more important.
2nd, set compression F & R on flat straight roads with the sort of surface you want it to work on.

3rd, set rebound on curvy bits with increasing speed until you get where you want to be.
There's no perfect setting for public roads, but it's good to know what you prefer in certain places. I keep mine pretty soft normally, but tighten it up significantly for the SSR because the roads are nearly flawless and very slow where the work is hardest.
 

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Glad to hear it is working out well. Suspension setting are almost always a compromise. It is hard to get one setting that works everywhere. But at least now when you turn the adjuster it makes a difference. That is a major upgrade in my opinion.

And I also agree with Pressureangle, getting spring rates right is a fundamental aspect of suspension tuning. and setting your sag should give you an idea of how close your spring rates are. That process has been discussed fairly extensively here, but if anyone wants to dig into that can of worms just let me know.

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G'day again folk's

Well managed to get out for a wee 250 k jaunt Sunday to try latest settings....

I'm quite happy ( bloody rapt actually!) with the Comp on + 2 and rebound on + 4 so think I'll leave it there for the time being. It seems to be a good compromise for our goat tracks!

Couldn't agree more about getting spring rate right and now I understand what all those road tests were on about under sprung and overdamped ha ha.

My set up now is .95kg straight rate springs ( I'm a kick in the pants off 90 kilos ) and forks as above with them up through the triples by 8mm and a Hyperpro 460 emulsion shock at the rear with a Hyperpro steering damper set at +4 .

One particular corner stands out that rams home the difference before /after suspension work.

It was a tightish but sweeping downhill right hander taken at 110 kays, road was wet and had a trace of mud / muck on it that was unavoidable. The feel from the front was brilliant and I knew exactly what was going on all the way through it. The old set up was vague through here even in the dry! 

Thanks again folk's.

Ps funny thing happened at the servo filling up before setting out. I pull in and lo and behold there's another Green V11 Sport at the pumps! I nearly fell off the bloody thing in shock and matey was just as stunned! Ha ha we had a laugh about you don't see two of these in the same spot....

Actually you just don't see two of these full stop ha ha !

Geez these things sound good eh!

Guzzler  

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Perfect timing. After putting 1500 miles on my black V11, the 1st upgrade I am planning for it is dialing in the suspension.
 How lucky I feel that all of you folks have carried the torch and advanced the technical knowledge for this quest while I was away. Winning! 
 This is one (of several) great thread(s) on these early forks. My own experience had me chasing compression damping 14 or so years ago. I never tried welding up those holes, or messing with the cartridges in any way, but I used thicker oil in the compression side fork only. It still lacked feedback. So those holes in the cartridge are the likely culprit! I think feedback is a product of compression damping and spring rate (in that order). On my silver bike I changed springs and set the sag on both ends (500 lbs/inch rear, progressive fronts) and now believe I should have went .90 - 1.00 kg/mm in the front (as guzzler did here). I also had my tubes above the top clamp by 10mm. In the end I could ride it pretty hard (I ran the old Pilot Powers), but I never really trusted the front. It would stick, but it wasn’t confidence inspiring! 
  The rear shock is the stock Sachs and spring. The front appears stock as well. The forks will come apart this winter. I will take photos and be asking which of the holes need blocking. The big name US aftermarket companies don’t have much info listed, and need some (a lot?) that I can trust! Anyone recommend a U.S. based expert on the forks?

Edited by FuelCooler
Clarity on which bike I am discussing!
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