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Ditto every bit of NoSquids excellent advice and explanation.
To include Öhlins very possibly supplying with the wrong spring, despite it allegedly being set up right for you. I do a lot of tuning and some sales of Öhlins, mostly on BMWs, and this happens all the time. And being that we're both lighter than average, it affects us significantly.

So, as NoSquid said, what is the spring rate printed on the spring.
It's not worth proceeding until you know that. But if you're totally topped
and have no motion when bouncing, then it is severely off. Likely indicating both rate and preload too high.

Also, the Öhlins, though very nice, tend towards pretty heavy high speed compression damping. Couple that with too much spring, and it may indeed feel very harsh.

Also, terminology varies, even among experts (I've had formal engineering courses in this, plus seminars from Foale and RaceTech) but generally, free and static sag are the same thing (how much the suspension compresses just under the bike's weight. The sag with you on it too is variously called rider/race/laden/total sag.

I prefer the method/check already described by no-squid.
Adjust laden sag to your preference (I like 35mm street and 30mm track or aggressive street) via preload. Then check your freesag. Anything from about 5-20 is borderline acceptable, but if you get 10-15 free/static sag, then your rate is about right. I'm very happy with an initial spring setup when it gives me sag numbers of 12 and 32mm. A few mm eitehr way is just quibbling, and you can then go up or down a rate depending on personal preference and how the bike is handling.

So, set your total sag to about 30mm and see if your free sag isn't about 10mm.
If so, you're OK. You could in that event, drop a spring rate for more comfort, but the harshness normally comes from severely mischosen rates, or much more often, too much high speed compression damping.

let us know your rate (from the numbers stamped on the spring) and your sag numbers. I bet we can get you set up well.
 

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You can safely assume that to have been sarcasm. Modern springs will settle little if any over any sort of reasonable timeframe. I wouldn't count on more than 2mm, if ANY.

What you have to be careful of in any tuning and setup work, be it carbs, injection, forks, or shocks, is the placebo effect. We tend to make observations in accordance with our expectations.

i.e. if we think that backing off of preload makes the shock feel softer, then we observe just that.

In reality, except for the special case of preload being so heavy the bike is topped, that does not happen. lowering preload does NOT affect plushness. Period. That is not the way springs work.

I encourage you to keep working on the setup. There's some good folks here that will help you and you'll learn a ton and have a better bike. Just keep and open mind and down let yourself believe a sugar pill is making you better. :)

Do let us know your rate along with the preload and sag
 

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Hi all,

What I don't get here, is that the sag numbers I get are a good deal different from what some of you (TWF et all) must see.

I don't recall my exact numbers, but they were on the order of static 10mm and race 30-35, which is normally about what I like. I too weigh about 145 and manage to get those numbers with a spring a bit under 500lb

For you light guys running 600lb or more springs, what kind of static sag are you running?
I'd think quite a bit to keep preload light enough to get race/rider sag right.

I understand all you're saying about setup, and agree, but I end up with significantly different rates to get reasonable sag numbers.

I'd like to see some guys chime in with some 4-point data sets
Rider Weight, Spring Rate, Static Sag, Race sag.


thanks
roger
 

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I've set up several with the circa '98 SRAD showa shocks.
99 and 00 1st gen models with riders on the light side. 140-155 lb
As said, that's given me sags of 10-ish/30-ish, with decent compliance and control.
I've had to make only minor shock valving mods, but that's probably down to having
springs that are only moderately stiffer than those shock bodies were equipped with.
I'm sure it's a whole different valving game when you throw on a spring that is 50-100% stiffer than original. But that's another topic.

I have to assume there's a whole in my knowledge specific to these SVs and or their linkage and/or their linkage in concert with the non-stock shocks, as I've never had trouble setting up many other bikes for myself or customers. Yet here, I'm seeing obviously suspension-savvy guys draw a different conclusion.

Makes me want to doublecheck myself and/or seek a bit of education/correction.

I'd be glad for any such insight, and thrilled to see a few examples of what others are getting for both sag numbers, along with thier weights and rates.

thanks in advance.
 

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Good point Jarel.
Yours is a fairly extreme example, with most SVs being fairly close (+/-10lb?), but the weight is worth taking into account.
Thanks

Still, I'd be curious what spring rate you get those numbers with. You listed everything BUT that.

Would like to hear from others too.

Thanks
Roger
 

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Jarel,

Too true. I do mostly street bikes, or near stock trackbikes, so my mind was on a narrow range, but you're quite right.

TWF, Generally measure to a mark scribed on top of axle nut, but I'm open to any suggestions.

Thanks
Roger
 

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Hmmm,

Those numbers make me think that you have about the right spring.
A bit more preload would move the sag to something like 10/30 or 12/32 (approx) and those are normally pretty good numbers. Certainly for the street. A much bigger spring would seem to show either to little static, or too much race sag. Of course a heavier guy or lighter bike might want more spring and less preload, but this seems about right for you.

Not sure how you'd get both sag numbers sensible with a 600 pound spring.
I don't mean that to give anyone crap, I'm just saying I dont' get it..
 
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