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YellowDuck

The Suspension Thread

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YellowDuck    0

As requested...here you go.

 

I have so much to post here - this really is my favorite topic by far.

 

Can we start with preload? This is truly my pet peeve. It is so poorly understood by 75% of riders, and you can always find someone who completely misunderstands it but will argue until they are blue in the face that their view of it is correct.

 

The big misconception is that, when you add preload (turn the preload adjuster in), you somehow compress the spring and make the suspension firmer. A huge fraction of riders labor under this misunderstanding. What really happens is that, when you add preload (say, 3 mm), the suspension simply extends by exactly that amount. So, your starting sag position is 3 mm higher, and you will have 3 mm more positive travel before it bottoms out. The spring compression does not change.

 

The only condition under which the suspension is made "stiffer" with added preload is the situation where the suspension is fully extended (e.g., full extension of the forks when the front wheel is off the ground). It will take more weight on the suspension to get it moving from the fully topped-out postion, but once it has any compression the spring rate is the same as it ever was (e.g., it will compress 1 mm for each 10 N (1 kg) of weight, if it is a 1.0 kg / mm spring).

 

Obviously we don't spend too much time with the suspension topped out, so suspension stiffness under that scenario is not terribly important. So, what preload really does is set the initial ride height and sag - it determines the ratio between available positive travel (compression) and negative travel (extension). That's it. It does not make the suspension firmer.

 

When you start talking about rear suspension, the average rider's understanding of this is even more incorrect. Because of the rising rate linkage ratios on most bikes, adding rear preload (and therefore extending the rear shock and increasing the swingarm angle) will actually make the rear suspension action *softer*. Yes, softer.

 

Even some well-known suspension tuners speak incorrectly about this issue, saying, for example, that when you add fork preload you also should increase rebound damping to help control the "extra energy stored in the spring". What's really happening is that you probably needed the extra preload because your corner speed was increasing and you were running out of positive travel. It was *you* and your high-G cornering putting the "extra energy in the spring", not the preload adjuster.

 

If anyone would like further explanation of preload and how it works, I have links I can share. There are some complicated exceptions to the basic picture above, especially when dealing with suspension where the topout springs are regularly engaged...but that is not Preload 101, that is the Master Class.

 

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YellowDuck    0

Hmmph....I guess I was hoping to generate some kind of reply....

 

This place is awfully slow lately. I hope that is because everyone is too busy riding!

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Kevin Kane    0

I at least ordered the book; thanks for that recommendation Hugh.

PS; loved the race report as well. - Go Dogs!

 

Rain

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drioannis    0

Most riders believe what they can see or feel. You put more preload on the springs "it feels stiffer, doesn't it"?Please share more.

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YellowDuck    0

Most riders believe what they can see or feel. You put more preload on the springs "it feels stiffer, doesn't it"?Please share more.

 

Nope. If you have 1.0 kg / mm springs in the forks (2.0 kg / mm for the two forks together), they will compress 1 mm for each additional 2 kg of force you apply, regardless of the preload setting.

 

The exception to this is if there is not enough weight on the forks to compress them at all (zero sag), and then you try to compress them from fully extended. For example, let's say you have one of the fork legs off the bike. It is fully extended, since the 1.0 / mm spring inside had to be compressed 20 mm to install the spring (that is the "installed preload"). There is 20 kg of tension in the spring , so you will have to apply 20 kg force to the fork leg to get it to start compressing at all. But once you do that, it will compress an additional 1 mm for every additional kg of force you apply.

 

Now turn in the preload adjuster 3 mm. The preload on the spring now totals 23 mm with the fork leg fully extended. You will have to apply 23 kg of force to get it to start moving, but after that each additional 1 kg of force compresses the fork leg an additional 1 mm, same as before.

 

With the forks on the bike, they will compress whatever distance they need to to support the weight that is on them - the fraction of rider + bike weight that bears on the front wheel. (I am ignoring the effect of geometry of rake here to keep it simple - the forks here are straight up and down). Let's say there is 90 kg weight on the front suspension, and there is no extra preload dialed in. Both springs were compressed 20 mm to install them in the forks, so with the forks fully extended they exert 40 kg of force. With the wheel on the ground and the rider aboard they must support an additional 50 kg, so the fork compresses 25 mm (1.0 kg / mm x 25 mm x 2 fork legs = 50 kg). Now all of the weight is supported and the "sag" is 25 mm.

 

Now you turn the preload adjusters in 2 mm. Fully extended the forks could now support 44 kg before they start to compress, so they only need to compress an additional 23 mm to support the remaining 46 kg. So what happened? You added to 2 mm preload, and the sag was reduced by 2 mm (went from 25 mm to 23 mm). That is, the forks just extended by 2 mm. Total compression in the springs is the same (22 mm preload + 23 mm sag = 45 mm total - enough to support 90 kg). The spring rate has not changed and you will still get 1 mm of fork compression for every additional 2 kg of force on the forks.

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YellowDuck    0

For those who like visuals, here is a diagram I made some years ago to explain how preload adjustments work. There is something very similar in Trevitt's book.

 

The parts of the figure A - E are as follows:

 

A. Spring is 600 mm long, and has a rate of 1 kg / mm. That is, it compresses 1 mm for each kg of force applied.
B. Spring has been installed. Preload adjuster is wound all the way out. With fork fully extended, the spring is compressed by 15 mm. This is the “installed preload”. Thus, it will take 15 kg of force to start compressing the fork. After that it will compress by 1 mm for each additional kg of force applied.
C. There is now 65 kg of bike + rider weight bearing down on the fork leg (130 kg across both legs). This causes the fork to compress by 50 mm from its fully extended length. That is, the first 15 kg is supported by the 15 mm spring preload, then the additional 50 kg compresses the spring 50 mm. Thus, with this load, the total “sag” in the fork is 50 mm.
D. Since 50 mm is too much sag, the preload adjuster has been wound in 10 mm. This extends the fork by 10 mm, so the sag is now 40 mm. Note that the length of the spring has not changed. Adding preload does not compress the spring, it just extends the fork. This is always true, except if the fork is topped out.
E. With the same preload setting as in D, the weight has been removed from the suspension. Now, there is 25 mm of preload (the 15 mm installed preload shown in B, plus the 10 mm preload added in D). Thus, it will take 25 kg of force to start compressing the fork. After that, it will compress 1 mm for each additional kg of force applied, as always.
Summary: Adding preload does not result in a spring that is more compressed in use, and therefore does not make the suspension feel “stiffer”. The suspension will still compress by the same amount per unit force applied, regardless of the preload setting. Adding preload merely extends the fork so that it has more positive travel available before bottoming.98722d1317910726-understanding-preload-p

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Kevin Kane    0

Hugh;

Good graphics & write up so a real world question. [i don't mean to hi-jack this thread with a specific question but I can't help myself] A rider starts to break heavily at the end of a long straight and the forks start oscillating (like a jack hammer) capturing almost all of the riders $10 dollars worth of attention - what's wrong with the forks here?

 

Kevin

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YellowDuck    0

That's not a thread jack at all - I was really hoping that we would start some discussion here where we could all share our experience and ask each other questions. It wasn't my intention to write a textbook!

 

Two thoughts on your question. The first thing I would do is monitor suspension travel with a a zip tie around the fork leg. If it is bottoming out, then there is your answer - you ran out of travel and bottomed the forks, so any additional bumps were delivered right up through the forks to the bike and rider. The question is, why? A common cause of this is too much rebound damping relative to the spring rate + compression damping. If the forks compress much more readily than they expand (because the spring rate is too light, the compression damping is too light, or the rebound damping is too heavy), then as you go over a series of bumps during heavy braking the forks will "pack down" progressively until you are out of travel. That's the most common cause of what you describe.

 

Second thought - this is a story from personal experience. I was experiencing a hammering through the front suspension in the braking zone at the end of the front straight at my local track. Yet my front suspension data acquisition system (zip tie) indicated that I had a good 20 mm of travel left. Big head scratcher.

 

I fiddled with a bunch of adjustments to no avail. Phoned Traxxion Dynamics who had sold me my fork internals. Their first question: "Are you sure it is the forks?" Of course I was - what did they think I was, an idiot? Second question: "Are you using the rear brake?". I reminded them my question was about the forks. They politely suggested increasing the air gap (i.e., dropping the oil level).

 

I was convinced that the fork positive travel must be somehow internally limited with the cartridges they sold me, so I had the forks off the bike and the springs out. Nope - they compressed right down to the dust seals; my "data acquisition" was giving correct information about available travel. So, I increased the air gap and reassembled.

 

Next track day, same problem, same place. I couldn't brake hard at all without getting that wicked front end chatter. Total despair.

 

Then I started paying attention and realized, much to my surprise, that I was indeed (unconsciously) applying rear brake! I stopped doing that. Problem gone. Instantly. 100% fixed. What I had been experiencing was violent rear wheel hop under hard braking, not front chatter. I couldn't tell the difference!

 

Morals of the story: 1. I am an idiot. 2. Take advice from experienced people seriously. 3. Sometimes it is not the solution that evades us, it is identifying the problem.

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Hotfoot    48

Love the story above, YellowDuck! Entertaining and educational. :) I recall my husband wrestling with a problem on his Ducati, he was getting some kind of rear wheel hop under heavy braking at the end of a straight; he thought it was from a rear suspension problem. Eventually he realized that that particular track had three big rolling bumps at the end of the straight that you couldn't see. They weren't huge but they were enough to bounce the lightened rear wheel off the ground. It wasn't the bike, it was just bumpy in that spot!

 

The first time I rode at Barber I thought my front wheel was out of balance, it had a weird vibration in front. I asked a mechanic, who politely informed me that the track is a bit ripply going up the hill from turn 3 and since you are hard on the gas there the front wheel floats across those ripples and makes it feel strange. Apparently I was not the first person to ask that sort of question!

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YellowDuck    0

 

The first time I rode at Barber I thought my front wheel was out of balance, it had a weird vibration in front. I asked a mechanic, who politely informed me that the track is a bit ripply going up the hill from turn 3 and since you are hard on the gas there the front wheel floats across those ripples and makes it feel strange. Apparently I was not the first person to ask that sort of question!

 

Ha! Nice one. I hope more folks post stuff like that.

 

Believe it or not I have at least three more topics related to springing and preload that I want to post about. One of them (the last one - it is the most advanced) relates exactly to the example you gave.

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Kevin Kane    0

Morals of the story: 1. I am an idiot. 2. Take advice from experienced people seriously. 3. Sometimes it is not the solution that evades us, it is identifying the problem.

Hugh;

I'm with Hottie here; great writing.

My issue was a recently acquired used AMA Pro Thunder 748SPS with heavy duty springs (the seller had close to 100lbs on me). I swapped them out for the original stock springs and never had chatter again and I track rode that Duc for ten more years. In the process of changing springs and refreshing the internals, everything was set to my weight when it was reassembled so I never actually knew what caused the hammer - but your answer was still awesome IMHO.

 

Kevin

PS - I am perplexed why we're not getting more commentary on your racing blog; regardless - go Dogs!

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YellowDuck    0

PS - I am perplexed why we're not getting more commentary on your racing blog; regardless - go Dogs!

 

 

I am quite certain that you are the Prairie Dogs' biggest (read: only) fan. Nonetheless the support is much appreciated! If we get another batch of T-shirts made up I am totally sending you one.

 

Oh, by the way....last SOAR round I ran into Brodie and told him he had something of a reputation around the CSS forum. He found that hilarious.

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Kevin Kane    0

Oh, by the way....last SOAR round I ran into Brodie and told him he had something of a reputation around the CSS forum. He found that hilarious.

That guy is not appreciated around here. At the last meeting of the Prairie Dog Racing Team Fan Club - "go dogs" party I attended, people were upset with that guy - big time!

 

...go Dogs!

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spike    0

I'm confused on B. If installed preload is 15 mm that means that there is 15 kg of force to get installed with all preload backed out correct? You say after this it will take 15 kg of force to get the fork to compress initially. Why wouldn't it be just 1 kg of force. I feel like the force exerted by the spring being installed would take care of that 15 kg needed.

 

Sorry if this doesn't make sense.

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YellowDuck    0

I'm confused on B. If installed preload is 15 mm that means that there is 15 kg of force to get installed with all preload backed out correct? You say after this it will take 15 kg of force to get the fork to compress initially. Why wouldn't it be just 1 kg of force. I feel like the force exerted by the spring being installed would take care of that 15 kg needed.

 

Sorry if this doesn't make sense.

 

Once installed, the spring is exerting 15 kg of force inside the fork tube, because the tube when fully extended is shorter than the spring free-length. That is, the spring is squished inside the tube even when the tube is fully extended to the stop. That tension in the spring is enough to support 15 kg. If you add more weight than that, it starts to compress the spring further and the tube halves can start to move relative to one another. It will compress until the additional tension in the spring is enough to support the additional weight.

 

Does that help?

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spike    0

I think I had a light bulb moment. Thinking back to physics two objects that exert the same force on each other won't move. One objects force increases to being greater than the other object it will then move the object with less force in the direction the force is being applied. It's a net force thing

 

Sometimes it just takes me a while.

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rchase    5

Great topic. Nothing useful to add here.

 

I'm just so glad that there are other people who understand the mysteries of motorcycle suspension. I'll keep reading. I might even learn something in the process. :)

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YellowDuck    0

Here's a trick related to measuring sag and setting preload...

 

Just about every article about measuring static sag reminds you that stiction in the system messes with the measurements, so that you need to measure sag based on the average of "stuck up" and "stuck down" measurements. I won't repeat all of those instructions here, but here is an example article of that type, from Andrew Trevitt:

 

http://www.sportrider.com/ask-geek-set-your-static-sag

 

This is especially important when making measurements on the forks, where the effect of stiction can be 10 mm or more (quite a big fraction of the 35 mm sag we might be targeting). With the rear suspension it tends to be much less important, since the spring force tends to be very large compared to the stiction in the shock and swingarm bearings. "Stuck up" and "stuck down" sag tend to be very similar at the rear.

 

Anyway, here is the not-so-commonly-known tip I wanted to share: Most people assume that stiction in the forks is due to friction between the tubes and the bushings and seals. This is true, but a significant amount of fork stiction can also derive from the hydraulics of the damping system. If you wind your rebound and compression damping adjustments completely out before making your sag measurements, you will reduce apparent stiction substantially and your stuck up and stuck down measurements will be much closer to one another. (If you don't have notes on your damping settings, remember to first turn them both full in, counting the clicks or turns, so you can put them back where you found them once you are done with your sag measurements.)

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shakabeemer    0

Watched your forks in action with interest in the video you posted on your racing blog. A light bulb went on and the thought was, "Oh yeah, that makes more sense now after digging into the book". A lot of the above is over my head for the time being, especially as I scramble to absorb everything I learned at Penguin 6/9/15. However, I'm determined, and I'm going to learn enough to get my suspension set properly and change it as needs change. Thanks again for opening my eyes with Andrew's book, your book, and and your writing, I will continue to follow your blog. Go Dogs!

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Kevin Kane    0

Go Dogs!

Ha! I told you the Dogs had a huge fan base here on the Forum; Nic is the president of the Long Island chapter.

He is bigger than me so when the Prarie Dog Racing tees are ordered make his a large and make mine a medium.

Go Dogs!

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Stroker    0

I had a very interesting introduction to preload. My friend had gotten a new bicycle with a rear monoshock. As he proudly explained this spring made the bicycle go faster, i examined it closely.

 

I found that i could make the spring longer or shorter by turning it.I made the spring as long as possible [ minimum preload ] and rode the bicycle.It offered a comfy ride on bad roads but moved far too much on tarmac.Trying to pedal hard meant most of the force was soaked up by the spring and i just bobbed up and down in the seat.

 

I made the spring as short as possible [ maximum preload ] and rode the bicycle. The ride was harsh and bouncy on bad roads but conducive to high speeds on tarmac. I could....put the power down so to speak and not bob up and down as before.

 

Of course, i has not heard of the term preload as a kid but have come to the following conclusions now -

 

1. Every rider weighs a certain amount, and the springs that hold him up must be set to work accordingly. If the springs are set to bear a rider weighing 50 kilos and a 100 kilo man sits on the bike, the springs act as if a 50 kilo rider is on the bike, and an extra 50 kilo force is being exerted by the bumps or whatever.

 

He therefore feels a lot of movement when riding around, the forks are diving on the brakes, the suspension feels soft etc.To eliminate these problems, the springs must be set such that - A 100 kilo rider upon the bike produces no movement. When extra force over and above the rider weight is exerted, the springs must compress and rebound as usual. Therefore preload tells the springs how much load will be put on them initially.

 

2. All straight rate springs produce equal amounts of compression for equal amounts of applied force. If a spring compresses 1mm for every kg force, you can take it for granted x kgs produce x mm of compression.

 

Progressive rate springs are those which produce varying amounts of compression for the same applied force. They will compress x, 0.8 x , .065 x etc for each kg force applied. These are usually not used in bike suspension.

 

Therefore, no matter how much preload you add or remove, the maximum extension remains the same.Preload only tells the spring - Start working soaking up forces greater than the riders weight, which is x kilos.If the spring is told [ by virtue of preload ] the rider weighs less than he really does, the spring treats the weight difference as added force that must be damped. If the spring is told the rider weighs more than he really does, the spring will pass on forces equal to the weight difference up to the rider and starts damping only after it experiences forces greater then the preload it's set to.

 

Therefore, it is imperative to set preload correctly first and then move on to compression and rebound damping. Incorrect preload means incorrect rebound and compression damping as a rule.

 

3. Most lower priced bikes come with preload adjustment. It is possible the soften or stiffen the suspension to a certain extent by adding or removing preload. Going two up for longer distances mean setting the preload to allow for the extra weight.

 

4. The range of preload adjustment is determined by the spring rate, spring length and number of coils [ correct me if i have missed any others ] . If you weight a certain amount , get springs that work best for that weight range. If you get a spring that works best for someone 25 kilos heavier than you, it's kinda pointless.

 

Thanks to all who contributed and YD for starting the thread. Can we move on to a discussion on setting sag? I have never done this, perhaps those who have can share their experience with pictures?

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khp    2

2. All straight rate springs produce equal amounts of compression for equal amounts of applied force. If a spring compresses 1mm for every kg force, you can take it for granted x kgs produce x mm of compression.

 

Thanks to all who contributed and YD for starting the thread. Can we move on to a discussion on setting sag? I have never done this, perhaps those who have can share their experience with pictures?

 

In addition to the physical spring, a front fork with an enclosed spring/fork oil* actually have another spring: the air volume above the oil. Since the air is in a closed box, it will work as a progressive spring, that should be added to the physical spring's rate (straight or progressive).

 

*) This includes both the Right-Side-Up ("Normal") and Upside-Down forks. I'm not sure if the BMW telelever fronts are included.

 

Setting sag has been described by several good people, including Paul Thede from Racetech and Keith Code (there's a section on the Twist-2 DVD where they show how to measure it).

 

Sag is calculated by measuring the distance between two fixed points, one point below the suspension and a point above the suspension. Measurements are taken independently on front and rear suspension.

Both Racetech and CSS recommend taking 5 measurements, measuring 3 things in total:

1) Fully extended length (1 time). Here, the wheel is off the ground to get the maximum extension.

2) Unweighted length (2 times). Length of suspension, when there is no rider on the bike.

3) Rider-loaded length (2 times). Length of the suspension, when the rider is on the bike, in riding position.

 

For (2) and (3), the measurement is taken twice: first time, the helper is gently lifting the suspension up, and let it down again to it's equilibrium. Second time, the helper pushes a little down and lets the bike rise back up to the equilibrium point.

 

For the sag calculations, the average of the two numbers are taken. Ideally, the two numbers should be identical, but if there is stiction in the suspension system or the two fork legs are not fully parallel (but wedges in/out like an A or V). This would especially show up when the rider is sitting on the bike.

 

"Free sag" is (1) - (2), while "static sag" is (1) - (3).

 

As long as I have a helper (or two), I have found sag measurement to be rather easy. As I recall, static sag should be around 30mm (1.2 inches) for a road bike.

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Stroker    0

Thanks for bringing up the air gap. Though i have an academic knowledge of it's working, i wonder if any of you have experimented with it and found what difference it makes?

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YellowDuck    0

I had a very interesting introduction to preload. My friend had gotten a new bicycle with a rear monoshock. As he proudly explained this spring made the bicycle go faster, i examined it closely.

 

I found that i could make the spring longer or shorter by turning it.I made the spring as long as possible [ minimum preload ] and rode the bicycle.It offered a comfy ride on bad roads but moved far too much on tarmac.Trying to pedal hard meant most of the force was soaked up by the spring and i just bobbed up and down in the seat.

 

I made the spring as short as possible [ maximum preload ] and rode the bicycle. The ride was harsh and bouncy on bad roads but conducive to high speeds on tarmac. I could....put the power down so to speak and not bob up and down as before.

 

Of course, i has not heard of the term preload as a kid but have come to the following conclusions now -

 

1. Every rider weighs a certain amount, and the springs that hold him up must be set to work accordingly. If the springs are set to bear a rider weighing 50 kilos and a 100 kilo man sits on the bike, the springs act as if a 50 kilo rider is on the bike, and an extra 50 kilo force is being exerted by the bumps or whatever.

 

He therefore feels a lot of movement when riding around, the forks are diving on the brakes, the suspension feels soft etc.To eliminate these problems, the springs must be set such that - A 100 kilo rider upon the bike produces no movement. When extra force over and above the rider weight is exerted, the springs must compress and rebound as usual. Therefore preload tells the springs how much load will be put on them initially.

 

2. All straight rate springs produce equal amounts of compression for equal amounts of applied force. If a spring compresses 1mm for every kg force, you can take it for granted x kgs produce x mm of compression.

 

Progressive rate springs are those which produce varying amounts of compression for the same applied force. They will compress x, 0.8 x , .065 x etc for each kg force applied. These are usually not used in bike suspension.

 

Therefore, no matter how much preload you add or remove, the maximum extension remains the same.Preload only tells the spring - Start working soaking up forces greater than the riders weight, which is x kilos.If the spring is told [ by virtue of preload ] the rider weighs less than he really does, the spring treats the weight difference as added force that must be damped. If the spring is told the rider weighs more than he really does, the spring will pass on forces equal to the weight difference up to the rider and starts damping only after it experiences forces greater then the preload it's set to.

 

Therefore, it is imperative to set preload correctly first and then move on to compression and rebound damping. Incorrect preload means incorrect rebound and compression damping as a rule.

 

3. Most lower priced bikes come with preload adjustment. It is possible the soften or stiffen the suspension to a certain extent by adding or removing preload. Going two up for longer distances mean setting the preload to allow for the extra weight.

 

4. The range of preload adjustment is determined by the spring rate, spring length and number of coils [ correct me if i have missed any others ] . If you weight a certain amount , get springs that work best for that weight range. If you get a spring that works best for someone 25 kilos heavier than you, it's kinda pointless.

 

Thanks to all who contributed and YD for starting the thread. Can we move on to a discussion on setting sag? I have never done this, perhaps those who have can share their experience with pictures?

 

I suspect your experience with bicycle suspension may have affected your view of how preload works. I don't know much about bicycles, but I can tell you for sure that much of what you wrote here does not apply to motorcycles.

 

For example, you found that adding preload made the spring shorter, and removing it made it longer. This will happen on a motorcycle too, but only if there is little or no weight on the suspension (e.g., bike on the rear stand with the wheel in the air and the swingarm fully extended). But once you put the bike back on the ground, as long as there is ***any*** sag at all in the suspension under the weight of the bike and rider (and normally, there should be sag even with just the bike weight), then the spring length will be exactly the same regardless of the amount of preload you added. The only difference will be the amount that the suspension had to sag to get to that spring length. When you added preload, the spring got shorter with the suspension fully extended, but ***only*** with the suspension fully extended. In use (i.e., with sag), the spring length will be the same, and therefore the tension in the spring will be the same.

 

Because the tension in the spring is the same, the "stiffness" of the suspension will not be affected by preload. Again, your bicycle experience may have given you the wrong impression. It is quite possible (I don't know for sure) that cranking in preload on a bicycle can result in a suspension that is fully extended under normal use - i.e., it is acting like a bicycle with no suspension at all. When you put enough load on it (e.g., by landing jump, or hitting a big bump at speed), only then would you get suspension movement.

 

On a properly set up motorcycle, this is not the situation at all. Since there is always static sag, and since the spring rate does not change, any given force always produces the same amount of movement - stiffness is the same.

 

The above applies almost exactly to forks, since they don't change much in terms of mechanical advantage. For a modern rear suspension, the above is not strictly true, because of the progressive linkage ratio - the amount the shock compresses for any change in swingarm angle actually changes with the swingarm angle. But in that case, adding preload usually has the *opposite* effect of what you described. That is, when you add preload, you extend the swingarm, and the resulting change in the linkage ratio makes the rear suspension *softer*, not stiffer.

 

Try to get your head around these basic ideas about preload and what it does. There is another subtlety related to topout springs that I hope we can cover before talking about damping adjustments. I know some of this is counter-intuitive, and your current ideas about spring preload are shared by a majority of riders.

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