How to tune your ShermanS / Patton / Lynx suspension 101

[Rawnei]

How to tune your ShermanS / Patton / Lynx suspension 101

I made this general guide because I see a lot of people who didn't tune their suspension for various reasons and also because someone asked me if I couldn't make a proper guide, tuning your suspension can be night and day in how it feels, even if you think it feels good out of factory it can feel even better when tuned and also be better prepared to tackle bigger obstacles.

I've helped all my friends who owns a LeaperKim FastAce wheel as well as people on Telegram and so far it seems people are happy with the end result.

These steps are applicable to any coil suspension wheel just that there are some specific details here for LeaperKim wheels with FastAce suspension but the basic concepts are the same.

Key Concepts:

Spring Rate:
This is how the spring inside is sprung and how much force it takes to get it moving, it correlates to your body weight and determines how much sag you will get when standing on the wheel, lighter riders need a smaller spring rate and heavier riders needs a larger spring rate.

Sag:
This is a crucial and important aspect of suspension, sag is how much the suspension compresses with you standing on the wheel, you want the suspension to be able to work in both directions thus some sag is desirable but with too much sag you don't get proper travel in the downward direction, sag is a result of spring rate and can be further tuned by adjusting pre-load.

Pre-Load:
Pre-Load is an important adjustment that you can make to adjust the sag, this should be the first thing you tune on your suspension wheel because it will become a baseline for the rest of the tuning.

Dampening:
There is also oil inside the shock working together with the spring that affects the movement of the shock, dampening determines flow rate of the oil inside the shock and will affect how fast or slow the shock can compress, with no dampening it can flow freely and with full dampening it's like locking the shock in place making it stiff.

Rebound:
Rebound determines how fast the shock will spring back from being compressed, with no rebound the shock will be very slow to bounce back and will "pack up", with too much rebound it will bounce back so fast that it feels like a pogo stick.

Tuning your suspension

Tuning Pre-Load/Sag:

Pre-Load is adjusted by using a 18mm wrench/spanner on the big golden hex shape on both sides, it is important that you set the same pre-load on both sides, you can see notches use those for reference to know how much pre-load you have.

So as I wrote tuning sag is crucial and should be the first thing you tune as it will affect both rebound and dampening.

Optimally you want sag to be somewhere between 25-30% of the total suspension travel (or close to it) which means:
Patton: 80mm travel sag should be between 20mm-24mm
Sherman S & Lynx: 90mm travel sag should be between 22mm-27mm

To tune sag you need a way to measure the sag, my method on LeaperKim wheels is to use a post-it note with markings on it where I make a line for 0mm then 25% and 30% respectively, I attach this post-it to the front on the battery shell and then I take something long and small such as an unused zip-tie, small pencil or similar and tape it to the fender so that it points to 0mm when not standing on the wheel.

Example photo from my Patton so you get the idea, in this photo I used 20%-30% as a baseline and ended up close to 30% sag:

Then you measure sag by standing on the wheel with your gear on, this is important because riding gear adds a bunch of weight, helmet, shoes, even backpack if you usually wear one, put them all on.

Caveat: I've noticed that putting full pre-load doesn't feel good, I can not explain why it's something specific with the FastAce shocks so if you need full pre-load to reach desired sag it is better to dial it back one notch and leave it at that.

Personal Example: I weigh around 105kg with all my gear and I'm considered a "heavy rider", my Sherman S and Patton are both 66lb variants and I use almost full pre-load on both (one notch visible) and get around my desired sag of 30% which is perfect.

FastAce shocks have no pre-load from factory.

Tuning Dampening:

Dampening is the "blue" side and is adjusted with a flat screwdriver or similar tool, turning it all the way to the left (counter-clockwise) means no dampening, turning it all the way to the right (clockwise) means full dampening, it will produce small clicks when turned that you can use as reference as to how much dampening you have.

Some riders might not agree with me but my opinion is that no dampening is the most desirable because it means the shock can be as responsive as possible.

So why even tune dampening? My personal opinion for our use case on EUC's it's solely for preventing bottoming out, besides spring rate it's our only tool for preventing bottom outs, bottom out on a LeaperKim FastAce wheel can be identified by a pretty audible "bang" when you land and fully compress the suspension.

Not everyone will need dampening, depends totally on how you ride, perhaps you are a street rider and would never bottom out even with 0 dampening then you really don't need to tune this but be aware that they do put a lot of dampening from the factory.

To adjust dampening do the most challening thing that you know that you will be doing with your wheel, do you like jumping? Then jumping is where you will tune dampening, keep turning the blue adjuster to the right until you no longer can hear the audible "bang", if you have difficulties hearing it while riding ask a friend to stand by and listen. If you do like to jump and other things you will be needing some dampening so start with 5 clicks from the left and go from there.

As a heavy rider myself who ocassionally do medium sized jumps I have 7 clicks dampening from the left and I don't get bottom outs, that leaves plenty of room for further adjustments and also doesn't affect the responsiveness of the shock too much, it stills feel very lively.

Tuning Rebound:

Rebound is the "red" side and is adjusted with a flat screwdriver or similar tool, turning it all the way to the right (clockwise) means slowest rebound, turning it all the way to the left (counter-clockwise) means fastest rebound, it will produce small clicks when turned that you can use as reference as to how much rebound you have.

Rebound can be an individual thing but in my personal opinion is that when suspension is working optimally it will make it so that you almost don't even feel small bumps, when the suspension works so well that it responds to every little bump that it almost feels like you're riding on flat terrain regardless how bumpy it is then you know that your suspension is working really well.

Just jumping up and down on the wheel to "feel" the rebound is meaningless, it will not simulate what you will feel when riding.

I tune rebound by using 2 different types of terrain:

1. A larger patch of uneven grass where you can gain some speed and distance, start with something like 6 clicks rebound from the left and go from there, the goal here is to ride with some speed (say 30kmh/20mph) over the grass and tune the rebound so that it feels as smooth as possible, usually this means lowering the rebound (click it to the right).

2. After tuning rebound on grass we have a baseline and it's time to find some uneven terrain with larger bumps/uneven surfaces such as a walking trail for instance, not something insane just something that is not completely flat, what you want to test here is to ride with some speed and see if the wheel feels "bouncy/springy" when riding over uneven terrain, usually this means lowering your rebound even more.

Rebound can take some time to dial in, doing the above will get you a good baseline but you might find that you need to tune it further when out riding.

Personally when I've found my optimal rebound it works for all scenarios regardless of how technical of terrain I ride it feels good all-around.

Closing Notes:

So that's it, hope you found this guide useful, you might not agree with all the steps and that is fine but hopefully you found something useful here, for me personally it is very important with optimal suspension and having suspension that will feel good in all scenarios and that is my goal when tuning suspension on all my wheels.

For easier tuning on the go and if you have access to a 3D printer (yourself, a friend, a 3D printing service) I designed this small tool that you can keep attached on your key-chain and bring with you so that you can tune on the go as needed, I recommend using this tool instead of the caps I also designed:

https://www.thingiverse.com/thing:6059508

Edited December 14, 2023 by Rawnei
Spelling

[carlitos]

I appreciate this post. I come from zero experience in tuning suspensions systems to my Patton so this article is great for me.

I have a dumb question: given a Patton with a 66lb spring rating, all suspension settings set to zero (no preload, no dampening, no rebound) and two riders, one 85Kg all-in weight and another one with an all-in weight of 105Kg,  when stepping on the wheel, will they get the same sag?

I would assume that the lighter rider would get less sag, for which they would have to increase the preload to reach the sweet spot.
And that the heavier rider would get considerably more sag, potentially beyond the sweet spot, then in that case they would need negative pre-load? This is where I get confused and where my question is from.

I guess maybe the pre-load has nothing to do with pre-compressing the spring but rather adjusting the height at which the joint sits?

[stizl]

1 hour ago, carlitos said:

… and two riders, one 85Kg all-in weight and another one with an all-in weight of 105Kg,  when stepping on the wheel, will they get the same sag?

…then in that case they would need negative pre-load? 

I guess maybe the pre-load has nothing to do with pre-compressing the spring but rather adjusting the height at which the joint sits?

They will not get the same sag.  The heavier rider will get more sag at the same preload. 

Since you can’t get negative preload, the only option to have less preload would be to get lighter rate springs, such as the 62lb springs. 

Preload exactly is pre-compressing the spring. The spring spec, such as 66lb, represents pounds of force per inch of spring compression.  For a 66lb/in spring, it requires 66lb of force to compress it one inch. Since these wheels have two springs, the total force required to push the suspension down one inch is doubled to 132lb. For a rider that weighs 66lb more than another rider to get the same sag, the heavier rider would need 66lb more total preload, or 1/2in more preload, since you have two springs. 

Edited November 11, 2023 by stizl

[Rawnei]

2 hours ago, carlitos said:

I appreciate this post. I come from zero experience in tuning suspensions systems to my Patton so this article is great for me.

I have a dumb question: given a Patton with a 66lb spring rating, all suspension settings set to zero (no preload, no dampening, no rebound) and two riders, one 85Kg all-in weight and another one with an all-in weight of 105Kg,  when stepping on the wheel, will they get the same sag?

I would assume that the lighter rider would get less sag, for which they would have to increase the preload to reach the sweet spot.
And that the heavier rider would get considerably more sag, potentially beyond the sweet spot, then in that case they would need negative pre-load? This is where I get confused and where my question is from.

I guess maybe the pre-load has nothing to do with pre-compressing the spring but rather adjusting the height at which the joint sits?

As @stizl wrote sag is relative to rider weight, that' is why different spring rates are better suited for different riders depending on their weight.

[carlitos]

Ok, great. Thanks your for answers.

So if I understand correctly, one can be too heavy for a spring because if without any pre-loading you are surpassing 30% of sag, that means that there is no head room for the pre-load since the rider weight already tossed that out of the window.

I played a bunch a lot with the dampening and the rebound until I got something that felt good but I never touched the pre-load.

I'm going to get to it.

Thanks again for sharing this valuable knowledge with the community.

[Rawnei]

9 minutes ago, carlitos said:

Ok, great. Thanks your for answers.

So if I understand correctly, one can be too heavy for a spring because if without any pre-loading you are surpassing 30% of sag, that means that there is no head room for the pre-load since the rider weight already tossed that out of the window.

I played a bunch a lot with the dampening and the rebound until I got something that felt good but I never touched the pre-load.

I'm going to get to it.

Thanks again for sharing this valuable knowledge with the community.

Not sure I follow, if you get more than 30% sag suspension still works but it won't be optimal, you will be losing travel, if you follow my method and measure it you will know how much travel you get.

[jugon666]

I have set both dampening and rebound at zero mainly because the axle clamps are already applying "by design" || (flaw?), a constant coefficient of friction against the battery casing which in turn acts as opposing force for movement to both directions XD . But hey nice walkthrough on how preLoad + dampening works on the leaperkim shocks ✌

[LaveyZFG]

Absolute brilliance, thank you for this guide! 

[Planemo]

On 11/11/2023 at 4:29 PM, carlitos said:

So if I understand correctly, one can be too heavy for a spring because if without any pre-loading you are surpassing 30% of sag, that means that there is no head room for the pre-load since the rider weight already tossed that out of the window.

I think you have it the wrong way round...if you have MAX preload and are still exceeding the 30% then the spring is too soft.

But...there is also the possibility that just because you can get the right sag does not mean things are correct. Eg you could have a heavy rider that has 30% sag at near max preload but will constantly bottom out when riding because the spring is simply too soft. All depends what terrain you ride. I run a (low) 750lb spring on my EX30 and have wound on quite a bit of preload to get 25% sag. So I'm kinda the example I use, but I don't jump etc so for me I get a real nice plush ride for the terrain I ride on, but someone else of my weight could probably bottom it out too often if they are a big off-roader. I very rarely hit bottom out, and regularly check my O rings just to see what things look like re travel used. Ideally, you want to be using as much of your travel as possible without bottoming, although an occasional one on an unusual big hit is fine.

As Rawnei says, the first thing you have to do is get the sag right and go from there. If it bottoms out, harder spring time. If you can't get 25~30% sag with preload backed right off, it's softer spring time

And as has been suggested, it's very rare we need any compression damping, theres simply too much stiction/friction in most systems, even MTB's tbh. A bit of rebound though, deffo. As a guide I usually wind it on until you can feel the wheel taking longer to return to sag position (jumping up and down on a static wheel). I then go from there after riding it on usual terrains. Bear in mind that for most systems I have come across the first 6 or so clicks do nothing! You will know when the rebound is starting to work though, the wheel will be like a pogo stick without it unless you have serious stiction issues

 

 

[Rawnei]

9 minutes ago, Planemo said:

I think you have it the wrong way round...if you have MAX preload and are still exceeding the 30% then the spring is too soft.

But...there is also the possibility that just because you can get the right sag does not mean things are correct. Eg you could have a heavy rider that has 30% sag at near max preload but will constantly bottom out when riding because the spring is simply too soft. All depends what terrain you ride. I run a (low) 750lb spring on my EX30 and have wound on quite a bit of preload to get 25% sag. So I'm kinda the example I use, but I don't jump etc so for me I get a real nice plush ride for the terrain I ride on, but someone else of my weight could probably bottom it out too often if they are a big off-roader. I very rarely hit bottom out, and regularly check my O rings just to see what things look like re travel used. Ideally, you want to be using as much of your travel as possible without bottoming, although an occasional one on an unusual big hit is fine.

As Rawnei says, the first thing you have to do is get the sag right and go from there. If it bottoms out, harder spring time. If you can't get 25~30% sag with preload backed right off, it's softer spring time

And as has been suggested, it's very rare we need any compression damping, theres simply too much stiction/friction in most systems, even MTB's tbh. A bit of rebound though, deffo. As a guide I usually wind it on until you can feel the wheel taking longer to return to sag position (jumping up and down on a static wheel). I then go from there after riding it on usual terrains. Bear in mind that for most systems I have come across the first 6 or so clicks do nothing! You will know when the rebound is starting to work though, the wheel will be like a pogo stick without it unless you have serious stiction issues

Dampening helps a lot to prevent bottoming out at least on LeaperKim wheels with FastAce suspension which is fortunate since it's not as simple as just easily changing the spring, also on LK wheels I would say definitely need some dampening if you are doing anything that is somewhat demanding of the suspension even if you have your sag and springrate dialed in, not a whole lot but some, suspension will still feel plush. My LK wheels with 7 clicks of dampening feels more plush than my S22 Pro with a Rockshox Vivid shock with low dampening tune and no dampening dialed in which is quite something.

With stock oil seals there seems to be varying degrees of stiction from owner to owner but when I swapped to SKF Showa seals on both my Sherman S and Patton it felt like there was no stiction at all, super smooth.

On a sidenote it's not dangerous to bottom out sometime, suspension should be able to handle it, just shouldn't be a common case scenario.

[Planemo]

28 minutes ago, Rawnei said:

Dampening helps a lot to prevent bottoming out at least on LeaperKim wheels with FastAce suspension

Oh I agree, comp damping will deffo help reduce bottom outs, but I really don't like using damp comp for this purpose, it should be handled entirely by using the correct spring. But I hear you re it maybe helping until if and when the rider changes the spring.

28 minutes ago, Rawnei said:

My LK wheels with 7 clicks of dampening feels more plush than my S22 Pro with a Rockshox Vivid shock with low dampening tune and no dampening dialed in which is quite something.

Indeed, just goes to show how good the LK solution is, despite using a relatively 'low quality' manufacturer. All those linkages and bushings on Begode and KS wheels are far from ideal. I'd like to look into replacing every crappy flange bush with a ballrace but it's not so simple, nor a topic for this thread.

28 minutes ago, Rawnei said:

SKF Showa seals on both my Sherman S and Patton it felt like there was no stiction at all, super smooth.

I change to SKF's asap wherever possible, they are definitely worth doing.

28 minutes ago, Rawnei said:

On a sidenote it's not dangerous to bottom out sometime, suspension should be able to handle it, just shouldn't be a common case scenario.

Agreed, it shouldn't be a problem, but clearly it is when the system is designed badly like all the mangled pivot bolts we have seen recently! (not used on the SS/Patton of course).

[Rich Sam]

I think its important to note that suspension settings and golden rules are based off other vehicles that use suspension, I.E. motorcycles, mountain bikes and such.  We are blazing new territory here using them on unicycles.  Equally important is mentioning that suspension settings are EXTREMELY personal to your style of riding and what you are\plan to do.  I like my suspension VERY tight and agile, I think 20% sag on an euc feels very sloppy.  I recommend everyone take this as a good starting point if you are a complete newb to suspension principles and mold and form your own opinions and style.

Edited November 15, 2023 by Rich Sam

[RagingGrandpa]

Lots of spring rate anxiety being shared lately...
But I feel that a 6% change in rate (between 62lb/in to 66lb/in) is a pretty small difference. 
Begod aftermarket involves far more dramatic changes: coil springs with rates varying by 30% on the same EUC.

Some example data: 
SS here, 62lb/in. Two springs, so total stiffness 124lb/in (2.2kg/mm).
I'm a 165lb riding weight, and let's assume 70lb of the EUC mass is 'sprung'. 
By the numbers, the suspension should sag about 1.9" under this 235lb load.

In reality, there is substantial installation preload, and I got 1.1" of sag without using the adjusters.
(And then I adjusted in another 0.3" of preload, allowing just a little more of the precious bump travel. This has no effect on stiffness or harshness.)

Every 10lb extra weight sags just 0.1" more. 
Every 5kg extra weight sags just 2mm more. 
And there's about 0.5" (15% of travel) preload adjustment available to help you, if you're too heavy for the spring.

Better to think about how you plan to ride.
Bottoming out can damage the EUC over time, so if you're planning on big slams, grab the big spring... you may have to tolerate riding a little higher, but it's safer.
And for the less abusive riders, I think everyone in the 140lb-250lb range (Lynx) could get within half an inch of an ideal sag, using 66lb.

TL;DR: My suggestion about rates is below, e.g.: all riders heavier than 195lb fully dressed should choose 70lb/in for Lynx.

(My numbers are based on an assumed amount of permanent preload in the strut assembly, derived from my SS measurements.)
 

And regarding 'soft' vs 'harsh' - there is far more than a 6% change available from the adjustable dampers. 
Please caution against new-rider feedback, unless they've spent 10 minutes on a rough surface exploring the full range of adjustment.

Edited December 6, 2023 by RagingGrandpa

[WILSONEUC]

Thanks @Rawnei, I have 66 spring option for both Patton and Sherman S and I never set my preload for either of them until just recently (last week). Let me tell ya , your guide is a valuable resource and a welcomed addition to the community.  I may be considered slightly overweight for the spring options that i have for both wheels, but the preload adjustments really add an extra layer of comfort to my ride and seems like the Patton/Sherman-S suspensions rebound and compression settings come a live after checking for the correct sag . The 66 lb seems for my body weight/gear average, is fine and no need to go higher.  

[Guilherme BR]

I have felt the suspension a little stiff for me (73kg - 66lb Sup). Can the "Pre-Load" setting make it softer?

[RagingGrandpa]

33 minutes ago, Guilherme BR said:

Can the "Pre-Load" setting make it softer?

No.

Preload only adjusts the mounting position of the spring, which we call sag. 
Adding preload raises you up. Sag is reduced.

Preload does not change the spring's stiffness, nor its length.
Ride quality is the same with full preload or zero preload, assuming you're not hitting the travel limits.

At 73kg with Patton 66lb, I think it will sag only about 20mm with no preload, prefect. There's no reason to raise it more, unless you're doing violent drops and are experiencing bottom-out. 

Edited December 13, 2023 by RagingGrandpa

[Rawnei]

24 minutes ago, Guilherme BR said:

I have felt the suspension a little stiff for me (73kg - 66lb Sup). Can the "Pre-Load" setting make it softer?

Have you checked your compression dampening setting?

[Guilherme BR]

1 hour ago, RagingGrandpa said:

No.

Preload only adjusts the mounting position of the spring, which we call sag. 
Adding preload raises you up. Sag is reduced.

Preload does not change the spring's stiffness, nor its length.
Ride quality is the same with full preload or zero preload, assuming you're not hitting the travel limits.

At 73kg with Patton 66lb, I think it will sag only about 20mm with no preload, prefect. There's no reason to raise it more, unless you're doing violent drops and are experiencing bottom-out. 

 

1 hour ago, Rawnei said:

Have you checked your compression dampening setting?

Thanks for the answers. I'm a casual rider, mainly in the city and I'm missing a little more cushioning.

Yes, I adjusted the dampening to 5 clicks to minimum...

[RagingGrandpa]

FWIW I like compression damping set to the minimum on my 62lb SS... (adjuster screw fully counter-clockwise). 
 

Edited December 13, 2023 by RagingGrandpa

[Rawnei]

47 minutes ago, Guilherme BR said:

 

Thanks for the answers. I'm a casual rider, mainly in the city and I'm missing a little more cushioning.

Yes, I adjusted the dampening to 5 clicks to minimum...

Considering you have good amount of sag, are you sure it's in the correct setting? (5 from left)? 

It shouldn't feel stiff.

[Jono]

On 11/11/2023 at 9:00 PM, Rawnei said:

How to tune your ShermanS / Patton / Lynx suspension 101

I made this general guide because I see a lot of people who didn't tune their suspension for various reasons and also because someone asked me if I couldn't make a proper guide, tuning your suspension can be night and day in how it feels, even if you think it feels good out of factory it can feel even better when tuned and also be better prepared to tackle bigger obstacles.

I've helped all my friends who owns a LeaperKim FastAce wheel as well as people on Telegram and so far it seems people are happy with the end result.

These steps are applicable to any coil suspension wheel just that there are some specific details here for LeaperKim wheels with FastAce suspension but the basic concepts are the same.

Key Concepts:

Spring Rate:
This is how the spring inside is sprung and how much force it takes to get it moving, it correlates to your body weight and determines how much sag you will get when standing on the wheel, lighter riders need a smaller spring rate and heavier riders needs a larger spring rate.

Sag:
This is a crucial and important aspect of suspension, sag is how much the suspension compresses with you standing on the wheel, you want the suspension to be able to work in both directions thus some sag is desirable but with too much sag you don't get proper travel in the downward direction, sag is a result of spring rate and can be further tuned by adjusting pre-load.

Pre-Load:
Pre-Load is an important adjustment that you can make to adjust the sag, this should be the first thing you tune on your suspension wheel because it will become a baseline for the rest of the tuning.

Dampening:
There is also oil inside the shock working together with the spring that affects the movement of the shock, dampening determines flow rate of the oil inside the shock and will affect how fast or slow the shock can compress, with no dampening it can flow freely and with full dampening it's like locking the shock in place making it stiff.

Rebound:
Rebound determines how fast the shock will spring back from being compressed, with no rebound the shock will be very slow to bounce back and will "pack up", with too much rebound it will bounce back so fast that it feels like a pogo stick.

Tuning your suspension

Tuning Pre-Load/Sag:

Pre-Load is adjusted by using a 18mm wrench/spanner on the big golden hex shape on both sides, it is important that you set the same pre-load on both sides, you can see notches use those for reference to know how much pre-load you have.

So as I wrote tuning sag is crucial and should be the first thing you tune as it will affect both rebound and dampening.

Optimally you want sag to be somewhere between 25-30% of the total suspension travel (or close to it) which means:
Patton: 80mm travel sag should be between 20mm-24mm
Sherman S & Lynx: 90mm travel sag should be between 22mm-27mm

To tune sag you need a way to measure the sag, my method on LeaperKim wheels is to use a post-it note with markings on it where I make a line for 0mm then 25% and 30% respectively, I attach this post-it to the front on the battery shell and then I take something long and small such as an unused zip-tie, small pencil or similar and tape it to the fender so that it points to 0mm when not standing on the wheel.

Example photo from my Patton so you get the idea, in this photo I used 20%-30% as a baseline and ended up close to 30% sag:

Then you measure sag by standing on the wheel with your gear on, this is important because riding gear adds a bunch of weight, helmet, shoes, even backpack if you usually wear one, put them all on.

Caveat: I've noticed that putting full pre-load doesn't feel good, I can not explain why it's something specific with the FastAce shocks so if you need full pre-load to reach desired sag it is better to dial it back one notch and leave it at that.

Personal Example: I weigh around 105kg with all my gear and I'm considered a "heavy rider", my Sherman S and Patton are both 66lb variants and I use almost full pre-load on both (one notch visible) and get around my desired sag of 30% which is perfect.

FastAce shocks have no pre-load from factory.

Tuning Dampening:

Dampening is the "blue" side and is adjusted with a flat screwdriver or similar tool, turning it all the way to the left means no dampening, turning it all the way to the right means full dampening, it will produce small clicks when turned that you can use as reference as to how much dampening you have.

Some riders might not agree with me but my opinion is that no dampening is the most desirable because it means the shock can be as responsive as possible.

So why even tune dampening? My personal opinion for our use case on EUC's it's solely for preventing bottoming out, besides spring rate it's our only tool for preventing bottom outs, bottom out on a LeaperKim FastAce wheel can be identified by a pretty audible "bang" when you land and fully compress the suspension.

Not everyone will need dampening, depends totally on how you ride, perhaps you are a street rider and would never bottom out even with 0 dampening then you really don't need to tune this but be aware that they do put a lot of dampening from the factory.

To adjust dampening do the most challening thing that you know that you will be doing with your wheel, do you like jumping? Then jumping is where you will tune dampening, keep turning the blue adjuster to the right until you no longer can hear the audible "bang", if you have difficulties hearing it while riding ask a friend to stand by and listen. If you do like to jump and other things you will be needing some dampening so start with 5 clicks from the left and go from there.

As a heavy rider myself who ocassionally do medium sized jumps I have 7 clicks dampening from the left and I don't get bottom outs, that leaves plenty of room for further adjustments and also doesn't affect the responsiveness of the shock too much, it stills feel very lively.

Tuning Rebound:

Rebound is the "red" side and is adjusted with a flat screwdriver or similar tool, turning it all the way to the left means slowest rebound, turning it all the way to the right means fastest rebound, it will produce small clicks when turned that you can use as reference as to how much rebound you have.

Rebound can be an individual thing but in my personal opinion is that when suspension is working optimally it will make it so that you almost don't even feel small bumps, when the suspension works so well that it responds to every little bump that it almost feels like you're riding on flat terrain regardless how bumpy it is then you know that your suspension is working really well.

Just jumping up and down on the wheel to "feel" the rebound is meaningless, it will not simulate what you will feel when riding.

I tune rebound by using 2 different types of terrain:

1. A larger patch of uneven grass where you can gain some speed and distance, start with something like 9 clicks rebound from the left and go from there, the goal here is to ride with some speed (say 30kmh/20mph) over the grass and tune the rebound so that it feels as smooth as possible, usually this means lowering the rebound (click it to the left).

2. After tuning rebound on grass we have a baseline and it's time to find some uneven terrain with larger bumps/uneven surfaces such as a walking trail for instance, not something insane just something that is not completely flat, what you want to test here is to ride with some speed and see if the wheel feels "bouncy/springy" when riding over uneven terrain, usually this means lowering your rebound even more.

Rebound can take some time to dial in, doing the above will get you a good baseline but you might find that you need to tune it further when out riding.

Personally when I've found my optimal rebound it works for all scenarios regardless of how technical of terrain I ride it feels good all-around.

Closing Notes:

So that's it, hope you found this guide useful, you might not agree with all the steps and that is fine but hopefully you found something useful here, for me personally it is very important with optimal suspension and having suspension that will feel good in all scenarios and that is my goal when tuning suspension on all my wheels.

For easier tuning on the go and if you have access to a 3D printer (yourself, a friend, a 3D printing service) I designed this small tool that you can keep attached on your key-chain and bring with you so that you can tune on the go as needed, I recommend using this tool instead of the caps I also designed:

https://www.thingiverse.com/thing:6059508

Great write up Rawni, I'm confused on one point on rebound damping and seeking clarification on "turning it all the way to the right means fastest rebound".

When you say right does than mean clockwise? For me that *increases* damping and *slows* the rebound. 

Cheers once again for the guide.

 

[Rawnei]

5 minutes ago, Jono said:

Great write up Rawni, I'm confused on one point on rebound damping and seeking clarification on "turning it all the way to the right means fastest rebound".

When you say right does than mean clockwise? For me that *increases* damping and *slows* the rebound. 

Cheers once again for the guide.

 

Right is clockwise yes, on all mine and my friends wheels (ShermanS's, Patton's) turning it to the right on rebound will make rebound faster.

[Planemo]

18 minutes ago, Rawnei said:

Right is clockwise yes, on all mine and my friends wheels (ShermanS's, Patton's) turning it to the right on rebound will make rebound faster.

Sounds bizarre, as Jono is suggesting, but I'm kinda inclined to agree with you based on the fact that my DNM shock is the same, clockwise *reduces* damping, it seems to to be the same on the Sherman too then! It's most odd, on every other shock I have played with (MC's/cars/MTB's) clockwise always *increases* damping, not decreases it. The DNM certainly caught me out because of this very unusual fact. Maybe it's just how things are done in China! (The DNM was the 1st Chinese shock I have come across)

[RagingGrandpa]

4 hours ago, Jono said:

clockwise
*increases* damping and *slows* the rebound. 

I agree with @Jono, and felt the effect myself.

Clockwise is labeled "Slow". It means more damping force: stiffer. 
 

[Rawnei]

Dunno what to tell you guys, I've adjusted at least 6 different LeaperKim wheels and they all behaved the same, left (counterclockwise) gave less rebound (rebound will not spring back as fast) and right (clockwise) gave more rebound (rebound will spring back faster) on every single one of them, same thing with compression dampening.

Mine has the same markings as pictured above yet the results that I wrote.