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View Results: Would you consider participating in a group buy?
Yes, if the price is right. 13 86.67%
No, these cartridges are way to expensive. 0 0%
No, USD forks will work so much better 2 13.33%
Voters: 15. You may not vote on this poll

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Old 07-27-2012, 10:30 PM   #706
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I am just glad that I haven't had time to install anything. I am sure you guys will have it sorted by the time I am ready . I am now wondering if I should go with the heavier weight oil, like Stagehand.
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Old 07-27-2012, 11:01 PM   #707
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Quote:
Originally Posted by One Less Harley View Post
This sucks, don't know why I'm bottoming out (175 mm and gators are compressed thus bottoming), and this only under moderate increasing brake.
It's mystifying.

I'm set-up per the instructions and pretty happy.

Brake-dive seems half of what it was with the stock set-up, and my sag only one band off recommended initial settings using the preload spacer Herr Hofmann sent.
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Old 07-28-2012, 01:38 AM   #708
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well my stuff is still in Auckland and now the package has been opened.Racetech are adamant they have the correct address on it.I have emailed Koko s contact hoping for an easy resolution
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Old 07-28-2012, 02:19 AM   #709
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Quote:
Originally Posted by supershaft View Post

The main advantage of using a shim stack in most of the models is finally being able to get enough rebound without too much compression. Separated damping? I don't think I would need a shim stack but that's just me. If I couldn't get what I wanted from different oil I suspect I would just modify my damper rods.
We are talking about forks here aren't we?

Doesn't having separate compression and rebound forks (such as the GS forks) accomplish that (at least to the point where you can manipulate each individually? Yet still they are found rather lacking by many (gold valve cartridge emulators seek to improve this).
I would think the main advantage of cartridge fork shim stacks over (orifice damping) damper rod forks would be the tunable non-linear damping?
This all gets a bit buried in confusing (to me) terms, however, where orifice damping gives you an extremely progressive (exponential looking) damping curve (often too soft at low speed and too hard at high speed), cartridge style shim stacks, due to their tunable non-linear damping, give you a much flatter (or to get real confusing, linear) damping curve- a curve that can be manipulated through the shim stack.

eg. from here
click for some explanation, but Q axis is veloicty, and P axis force, curve A is basically an orifice damper, and the solid line B something more like a shim stacked cartridge damper would provide.




My point about the compression and rebound adjusters and how in an ideal situation one should have the adjustment set closer to the maximum is that this means the shim stack is flowing most of the oil (giving the advantage of the desired damping curve it provides), rather than the bleed valve flowing the oil which is essentially just another (variable) orifice. (You get most of the oil flowing through the shim stack and a little bit of adjustment to play with if for some reason you want to get a bit more damping)
Does that makes sense? At least that is how I believe my (WP50) forks and adjusters work. I have read about different ways that damping can be adjusted (which might nullify this argument), but I was under the impression most damping adjustable forks worked this way.
Again, back to the whole point, if you are running a cartridge fork with adjustable damping (when the adjuster is a bleed valve) set on or near the minimum, then it might be worth looking into getting your forks re-shimmed.

and please understand, this is just a discussion to help me understand this stuff rather than a debate. I don't know enough to debate.


OLH. It seems something odd is happening to you. How did your sag numbers compare to the others again? Considering the others are having much better results, It sounds like it must be something something simple...
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Old 07-28-2012, 08:05 AM   #710
One Less Harley
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Quote:
Originally Posted by Stagehand View Post
your gaiters are compressing, but are you clunking out on bottom? I am probably compressing the gaiters all the way, who knows but I am not feeling the thing hit any limits of any kind over 99% of what I'm hitting, and I'm hitting ti as hard as I dare.
No clunking, but if gators were removed I sure it would be easy to max the forks out....that's what I don't want or like. IMO this shouldn't be happening.
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Old 07-28-2012, 12:38 PM   #711
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Quote:
Originally Posted by ontic View Post
We are talking about forks here aren't we?

Doesn't having separate compression and rebound forks (such as the GS forks) accomplish that (at least to the point where you can manipulate each individually? Yet still they are found rather lacking by many (gold valve cartridge emulators seek to improve this).
I would think the main advantage of cartridge fork shim stacks over (orifice damping) damper rod forks would be the tunable non-linear damping?
This all gets a bit buried in confusing (to me) terms, however, where orifice damping gives you an extremely progressive (exponential looking) damping curve (often too soft at low speed and too hard at high speed), cartridge style shim stacks, due to their tunable non-linear damping, give you a much flatter (or to get real confusing, linear) damping curve- a curve that can be manipulated through the shim stack.

eg. from here
click for some explanation, but Q axis is veloicty, and P axis force, curve A is basically an orifice damper, and the solid line B something more like a shim stacked cartridge damper would provide.




My point about the compression and rebound adjusters and how in an ideal situation one should have the adjustment set closer to the maximum is that this means the shim stack is flowing most of the oil (giving the advantage of the desired damping curve it provides), rather than the bleed valve flowing the oil which is essentially just another (variable) orifice. (You get most of the oil flowing through the shim stack and a little bit of adjustment to play with if for some reason you want to get a bit more damping)
Does that makes sense? At least that is how I believe my (WP50) forks and adjusters work. I have read about different ways that damping can be adjusted (which might nullify this argument), but I was under the impression most damping adjustable forks worked this way.
Again, back to the whole point, if you are running a cartridge fork with adjustable damping (when the adjuster is a bleed valve) set on or near the minimum, then it might be worth looking into getting your forks re-shimmed.

and please understand, this is just a discussion to help me understand this stuff rather than a debate. I don't know enough to debate.


OLH. It seems something odd is happening to you. How did your sag numbers compare to the others again? Considering the others are having much better results, It sounds like it must be something something simple...

I know cartridge forks are better but if I could get the damper rods working good enough I wouldn't need them I suppose. You can get forks working real well without them.

I understand your point about re-shiming your stack in order to get into the middle of the adjuster where ever that is for you. That all makes sense and is probably what I would do but my advise about running as little damping as possible still holds water with that in mind. How many shims are on your stack always changes everything as far as how many click gets you so much damping.

The main thing is I am glad you guys are figuring out that the adjusters barely adjust. They are for FINE tuning the right number of shims whatever that might be for you or for fine tuning the preload AFTER you get it real close to what you want with spacers. It's a LOT of work and a LOT of money if you want to check out different springs. Good luck and thanks Sh.
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Old 07-28-2012, 06:10 PM   #712
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Quote:
Originally Posted by One Less Harley View Post
BTW- HH did mention a couple of times a 10mm spacer could be used to increase preload if needed.
Can one of you guys measure the O.D./I.D. of the spring spacer and share those dimensions with me?
I want to turn down a pair of shims and install them with little down time.
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Old 07-28-2012, 06:47 PM   #713
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Quote:
Originally Posted by Renner View Post
Can one of you guys measure the O.D./I.D. of the spring spacer and share those dimensions with me?
I want to turn down a pair of shims and install them with little down time.
The OD of the spacer is 30mm (1.182 inches), the step in that fits into the spring is 23.13mm (0.911 inches) and the hole through the spacer is 18.73mm (0.747 inches)

I hope that makes sense.
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Old 07-28-2012, 08:22 PM   #714
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Quote:
Originally Posted by Renner View Post
Can one of you guys measure the O.D./I.D. of the spring spacer and share those dimensions with me?
I want to turn down a pair of shims and install them with little down time.
why the spacer??? I thought you were pleased. So you're no where near full compression of the gators under even hard braking??? Springs seem soft to me, but bad thing is I know nothing about suspension setup. They seem to take road bumps ok, need to get out on some dirt/gravel though.
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Old 07-28-2012, 08:30 PM   #715
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Here is huberts response to me regarding sag and spacers:

70mm sack is ok. 75mm sack is little more is not bad. You sink is too soft , make 10 mm more preload spacer.
Between *spring und the catridge tube. Is possible for you make spacer tube *with inside 24mm outside 30,mm and 10mm long ? Is this still too soft for you I can send you the harder spring and spacer
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Old 07-28-2012, 09:18 PM   #716
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Quote:
You sink is too soft , make 10 mm more preload spacer
Couldn't help it :-)

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Old 07-28-2012, 10:33 PM   #717
Renner
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Originally Posted by One Less Harley View Post
why the spacer???
Playing with the geometry.

My first time with the R100GS forks on the R80ST and I want to reduce trail by raising the stanchions in triple tree.
It's now up 7mm but no further due to the bars being in the way, and I'm reluctant to go with bar risers.

So I'm thinking to put some of the adjusted preload inside the forks to gain clearance.
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Old 07-29-2012, 01:54 PM   #718
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Sorry, slightly off-topic question, could someone please confirm that I need a 37mm socket to undo the nut at the top of the fork triple clamp? I need to do the steering head bearings on my G/S.
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Old 07-29-2012, 07:29 PM   #719
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My impressions of the .48 springs on the road- absorbs bumps well not harsh at all, mostly focusing on compression for now +1.75 turns in from topped out("0.00" being topped out +3.50 fully bottomed out), doesn't seem to bottom out when hitting 3" curb or 4" gravel "bump". I need to get out to some gravel and play with settings more. I've got about 65 mm of SAG (5 rings on preload), but would like less, maybe 58mm, as that is 1/3 of 175 mm. Reason I'm quoting 175mm is because that is the max usable travel with gators in place. Gators act as a rubber bump stop. I haven't actually confirmed the spec of 225mm that BMW list as fork travel. The front dives quickly under braking and uses all of the 175mm of fork travel when coming to a fairly quick stop (quicker than my usual sedate stops), I don't like that!!

Herr Hofmann, is sending me .58 springs and some spacers to try. Not sure if spacers will be 10mm and 20mm as he mentioned sending 20's. I don't like the idea of putting the AL spacer at the bottom of the spring as it will be hard to retrieve, but a temporary solution may be to tie it to the spring so it can be switched out easily. If the spacer is needed then I'll turn a new top spacer but make it longer, this will make changing easier.
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Old 07-29-2012, 08:30 PM   #720
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I think in real world situations, the gaiter wouldnt really do anything in terms of acting as a compression stop. It might be tough to compress it by hand, but a 600 lb bike/rider combo at 45mph is a lot more than a little rubber boot can hold back, I would think, no?
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