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Original rear shock


activpop

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@Lucky Phil, Right on about the Wilburs. I ran the spring numbers and from what I found out the spring might be the weak link. It is a 50-50-100-130. I'm thinking the third number could be 130 for my weight with riding gear. 230lbs- 104kg. I have to see how to change that spring or who can do that.

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33 minutes ago, activpop said:

@Lucky Phil, Right on about the Wilburs. I ran the spring numbers and from what I found out the spring might be the weak link. It is a 50-50-100-130. I'm thinking the third number could be 130 for my weight with riding gear. 230lbs- 104kg. I have to see how to change that spring or who can do that.

Springs are rated for the weight that will compress them a specified distance.  My Öhlins spring ends with "90". This turns out to indicate 90N/mm (about 514 pounds per inch). So your "100" or the "130" may be the "rate" (N/mm).

I could not find your numbers at the Wilburs (AUS) site, but they invite inquiry:

https://wilbers.com.au/index.php?route=product/product&product_id=862

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@doccThanks, I will contact them. If anybody has answers, they do. 

Here is an interesting reply to a question posted up on an old GS thread. Some good info here.

Hi, I have Wilbers (front/rear) on my R12GS since more than 30000km. I understand the basics so perhaps I can help out.
The most important part on the number combination on your spring is the '150' indicating the spring rate.
My Wilbers springs carry the same numbers, and I weigh 86kg, and the pillion weighs 70kg, and then there's the luggage. So you're allright as far as springrate goes. Springrate on these bikes is usually 140, 150, 160.

Now some basic info. Imagine a bike hanging in the air. As it comes down and sits on it's springs, it goes down a bit called the 'static' sag. As a rider mounts the bike, it goes down even more : the 'dynamic' sag. The 'dynamic' sag is supposed to remain equal, no matter how much weight is put on the bike; that's why there's a preload knob for adjustment. The trouble is that it's not easy to find out what the basic dynamic sag is, i.e. when riding solo.

That's where Wilbers are clever : in the factory they put the minimum preload according to weight of rider (as specified when ordered). This exact minimum preload means that the rider will have the correct dynamic sag when riding solo. From there on, he can adjust for more weight by increasing the preload.*

What some people don't realise, is that this factory installed minimum preload can be altered on the spring, for more or less solo weight. Otherwise Wilbers would have to produce hundreds of different springs for different riders' weights. And as a nice advantage to us customers Wilbers springs/dampers can be sold on to a rider with a different weight.

To be specific : you have bought a second hand Wilbers and can have the minimum preload changed so that it fits your weight (preferably by someone who knows how). But, since you are heavier than the specified weight you have this option : when riding solo you can simply adjust the preload above the minimum installed by the factory. This means trying out different preload positions and measuring dynamic sag 'till you get it right for riding solo.
(To make it clear : if you were lighter than the specified rider weight, you would imperatively have to get the factory installed minimum preload decreased, or accept to ride solo with slightly wrong dynamic sag).

As far as damping (rebound) goes, this is a Very Personal Matter. Damping influences roadholding AND comfort. The best way to find out what YOU like, is to testride the bike with different damping settings. If the damping is too open, the bike will start wallowing around, perhaps plushy, but not efficient in roadholding. With the rebound damping too closed the spring will not have the time to rebound before the next bump arrives, actually diminishing spring travel, diminishing roadholding... and the ride will get uncomfortably hard. It is false to think that a hard damping setup will result in better roadholding. In any case it's a compromise that you have to find out for yourself.

Here's what I did : I went on a calm stretch of road with different curves and changing 'bumpiness' (that's important), and tried out different settings, always driving the same stretch. I opened the damping completely to understand the consequences, then closed it completely for the same reason, and then worked with small adjustments till I got it right to my taste. It took me a couple of hours. I like technique so I had a blast. :D

For those who think this is all too complicated : it isn't, it's actually easy and a hoot ! And the reward is : an incredible improvement over the BMW stock solution.

I'm convinced you'll enjoy your Wilbers !
Have fun:thumb !

* And here's the big difference with preload on a standard BMW spring : since BMW don't know how heavy the rider is, preload is set somewhere in the middle. It's up to the rider to find out the exact amount of preload he has to install for riding solo. This means the rider has to know about dynamic sag, and measure this for himself. I don't know dealers who explain this, I know even less riders who ride with the right basic set up. BTW the same basic error (BMW not knowing how heavy the rider is, and thus possible wrong preload) exists with ESA.

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From what I understand, the 100 is the number that correlates to rider weight. It seems too low for my weight. Doesn't feel the best on the road. I'll be checking this stuff out today.

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Having riding about 20k on a set of Wilbers (2010 MG V7 Café Classic), I'll also recommend keeping and correcting them. They are incredibly adjustable, reliable, and no maintenance.

With that said, you mentioned selling within the month. Then I'd venture to say, leave it alone. The next guy can set it up for his body weight, preference. It doesn't make sense to spend money, only to turn around and sell it. You'll lose every extra dollar you put into it. 

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For what it is worth, it looks bit like it might be possible to buy the hydraulic pre-load adjuster as an accessory part, i.e. buy it and retro fit it, or in your case (maybe) put it back on:

https://www.wilbers.de/en/products/shock-absorbers/optionsaccessories/hyd-preload-adjuster/hydraulic-spring-preload-type-625.html

 

However, as has been said, if you're planning on selling, let the new owner worry about it. B)

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23 hours ago, activpop said:

@Lucky Phil, Right on about the Wilburs. I ran the spring numbers and from what I found out the spring might be the weak link. It is a 50-50-100-130. I'm thinking the third number could be 130 for my weight with riding gear. 230lbs- 104kg. I have to see how to change that spring or who can do that.

I found this considered post by a fellow on AdvRider:

"The first numbers appear to be the ID of the spring in millimeters with both ends specified.
The second number appears to be the spring rate in Newtons/mm (conversion = 5.71:1 to get to lbs/inch).
And, the third appears to be the spring length in millimeters.
"
 

I would think that the spring rate would suit your weight. If the sag is acceptable, I would leave it alone.

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1 hour ago, docc said:

I would think that the spring rate would suit your weight. If the sag is acceptable, I would leave it alone.

Thanks for your digging @docc. I talked to the Wilburs dealer In CA. He gave me that info along with proper unweighted and sag measurements. I will do the figuring to check it out. Learning something everyday! :luigi:

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On 3/27/2024 at 10:17 AM, activpop said:

From what I understand, the 100 is the number that correlates to rider weight. It seems too low for my weight. Doesn't feel the best on the road. I'll be checking this stuff out today.

As mentioned, there isn't going to be a number printed on the spring that corelates to the riders weight. There are too many other variables involved to make that possible. The spring only knows its own rate, as well as its length. It doesn't know the ratio of rear suspension travel to shock / spring travel.

If you measure and set the sag of the bike with you sitting on it, then measure how much sag there is without you sitting on it, that will tell you how the rate of the spring is. Too much sag without you on the bike after setting the sag right with you on the bike means the spring is too stiff. Too little sag without you on it after setting the sag correctly with you on it means the spring is too soft. That can seem backwards, but it is right. Too little sag without you on the bike means you had to add too much preload to the spring to get the sag with you on the bike correct. That excessive preload means that without you on the bike the bike sags very little. The opposite can also be true, too stiff a spring means you don't need much preload to get sag right with you on the bike, so with so little preload the bike will sag too much without you on the bike.

Different people have slightly different versions of the target numbers for sag, but generally you want somewhere between 25 - 30 percent of total travel use up by sag with you on the bike, and only 10 - 15 percent sag under just the weight of the bike. Some people like a little more sag, some like less. One thing to keep in mind, more sag with you on the bike does not mean the spring is softer, only that it has less preload. With less preload, the suspension rides lower in its travel, that can be good, or it can make for a harsh ride if it leads to more bottoming of the suspension. I think you want the suspension to ride high enough that the suspension doesn't bottom very often, if at all.

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1 hour ago, GuzziMoto said:

 I think you want the suspension to ride high enough that the suspension doesn't bottom very often, if at all.

But also not so high that it tops out... :oldgit:

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From what the Beemer Shop told me(Wilburs dealer), you take full wheel travel of 128mm on a V11, measure that from two reference points. That will be with rear in the air at full extension. Then measure same distances with you sitting on it. Your target is 30% of the first number. From there you adjust to get to that 30% number. I wont have time to do that for a couple weeks...life is getting in the way again. 

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13 minutes ago, activpop said:

...life is getting in the way again. 

Yeah, it does that, doesn't it?

Thanks for the number (128mm). That is for the rear shock, I take it, as that is what this topic is about. I've been looking for a number for that.

I'd be interested in a number for the 43mm Marzocchi forks with rebound adjustment on both legs too. :)

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17 hours ago, audiomick said:

Yeah, it does that, doesn't it?

Thanks for the number (128mm). That is for the rear shock, I take it, as that is what this topic is about. I've been looking for a number for that.

I'd be interested in a number for the 43mm Marzocchi forks with rebound adjustment on both legs too. :)

There have been different numbers given for total suspension travel for the rear of the V11 Sport. But the difference between 128mm, 120mm, or 135mm, is too small to worry about when you are only talking 30% of the difference.

The forks are easier to measure travel, just lift the front end slightly off the ground so the front forks are completely extended, then measure the distance / length of the exposed slider tube. Full fork compression is when the entire slider tube is stuffed into the outer tube. So the exposed length of the slider tube is pretty much the amount of available suspension travel in the front forks. As with the rear, being exact is not important. Within 5 or 10 mm is good enough. Keep in mind that if you are 10mm off in your total travel number once you take 25% or 30% of that you are talking an actual difference of 2.5mm - 3mm. Just not something that is going to make a difference in the actual outcome of setting sag.

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