Tractive closed cartridge

[Tenerider]

30 minutes ago, Ray Ride4life said:

I checked my Touratech instructions, these are the same as the Tractive. Touratech gave Tractive a lot of money to develop them and Tractive was not supposed to sell them under their own brand but that's another story and maybe they changed something after all to avoid lawsuits.
My instructions give 10 clicks from zero as the baseline and is advised not to go more than +/- 6 clicks of that baseline so in my book that will be no problem to go 7 or 8 clicks off.
I think you can see it as a Co² or Argon bottle on a welding machine. When you open it fully to the end and start welding it can be very hard to close it again, open it and then turn it halve a turn back to close to prevent it.

Same recommended settings as with Tractive labeled items.

Only difference is the recommended air chamber: 120mm (Tractive) vs 130mm (Touratech). The latter should offer more responsiveness vs less protection against bottoming out, according to my Tractive distributor. They recommend a smaller air chamber for aggressive riders and high loads, and a bigger chamber for light riders.

But then, they all have PDS II anyway...

[Ray Ride4life]

3 minutes ago, Tenerider said:

less protection against bottoming out

The closed cartridges have an hydraulic bumpstop to catch bottoming out.

[Tenerider]

7 hours ago, Ray Ride4life said:

The closed cartridges have an hydraulic bumpstop to catch bottoming out.

I know, anyway, that's what my dealer said. They know the hydraulic bump stop, but the smaller air chamber seems to add progression to the end of the stroke, so you have less chance of hitting the hydraulic end stop. I'm just quoting what they said.

I rather prefer a more sensitive working suspension and then accept bottoming, especially since there is the hydraulic bump stop.

[Jason]

So I discovered something this week. I was debating over the weekend ordering the lighter springs, I made the call to pull the trigger because after spending so much money on the setup to begin with. I wanted it to be perfect. So I get back onto the retailer to order the new springs. 
 

(I say back onto the retailer because I spoke to both them and Tractive directly back in January as I felt the suspension was way too harsh) 

 

Anyway after a lot of back and forth, I realised when they sent the product code for the new spring that my current springs were wrong. I was sent the +20mm spring for my forks and never realised. Retailer has been tough to deal with and is making me order the new springs instead of sending them to me for free as it was their mistake. Says I’ll get a refund if I send the originals back to him but the cost of shipping from Ireland to Germany is out of my pocket. 
 

anyway. New springs inbound - I’m delighted to know I wasn’t going crazy. While the forks were still a huge improvement on what the originals were. I always. New something wasn’t right, can’t wait to get the proper springs fitted - Watch this space

[Tenerider]

This sounds strange. AFAIK, both cartriges use the same spring length. That's why the +25mm cartridge comes with more spacers, to generate the needed preload.

I have asked my dealer regarding the preload spacers, he checked it and said that both cartridges use the same spring length (that's how I know).

 

I came across another thing recently: Race Tech have a spring rate calculator on their website for a vast amount of bikes, including rider weight (without gear), riding style and personal preference:

RT - Digital Product Search

Bret Tkacs recommended it in one of his videos, and he said he'd personally go one spring lighter than recommended there.

Of course I entered my data and got springs around 7 N/mm recommended - my weight without gear is 82 kg.

My Tractive dealer recommended 6.4 N/mm which would be one or two steps lighter than recommended by Race Tech.

Ok, this is for OEM forks, but should not be different on other cartridges.

 

Furthermore, I've recently bought the Race Tech suspension bible, HIGHLY recommended. There are a lot of other factors to be checked when the suspension feels harsh (binding, friction, oil level, ...).

Edited March 15, 2023 by Tenerider

[Jason]

10 minutes ago, Tenerider said:

This sounds strange. AFAIK, both cartriges use the same spring length. That's why the +25mm cartridge comes with more spacers, to generate the needed preload.

I have asked my dealer regarding the preload spacers, he checked it and said that both cartridges use the same spring length (that's how I know).

So they actually have different cartridges and springs. Here’s the comparative image, you can see one spring length is 390mm for use with long travel setups and then the standard is 370mm

[Tenerider]

2 minutes ago, Jason said:

So they actually have different cartridges and springs. Here’s the comparative image, you can see one spring length is 390mm for use with long travel setups and then the standard is 370mm

Thanks! This makes a difference for sure - 20mm preload on the longer ones if they are installed in the normal cartridges.

[Jason]

4 minutes ago, Tenerider said:

Thanks! This makes a difference for sure - 20mm preload on the longer ones if they are installed in the normal cartridges.

Ye absolutely, I ordered the same spring rate again anyway so I’ll see how I go. But this is going to make a big difference for sure

[Windblown]

6 hours ago, Tenerider said:

This sounds strange. AFAIK, both cartriges use the same spring length. That's why the +25mm cartridge comes with more spacers, to generate the needed preload.

I have asked my dealer regarding the preload spacers, he checked it and said that both cartridges use the same spring length (that's how I know).

 

I came across another thing recently: Race Tech have a spring rate calculator on their website for a vast amount of bikes, including rider weight (without gear), riding style and personal preference:

RT - Digital Product Search

Bret Tkacs recommended it in one of his videos, and he said he'd personally go one spring lighter than recommended there.

Of course I entered my data and got springs around 7 N/mm recommended - my weight without gear is 82 kg.

My Tractive dealer recommended 6.4 N/mm which would be one or two steps lighter than recommended by Race Tech.

Ok, this is for OEM forks, but should not be different on other cartridges.

 

Furthermore, I've recently bought the Race Tech suspension bible, HIGHLY recommended. There are a lot of other factors to be checked when the suspension feels harsh (binding, friction, oil level, ...).

 

Spring rate is usually the same (or very close) for a given bike/rider regardless of the brand of suspension and even between two different bikes of the same weight - but only if the suspension travel is the same and the shock linkage ratio is the same.  If the suspension travel or linkage ratio changes all bets are off.

 

If you increase the suspension stroke then lighter springs should be used, decrease the suspension stroke and heavier spring should be used.  The reason for this is that you want to use the suspension available without crashing into the stops.

Longer stoke? You want to be able to make use of it so you'll need lighter springs that let the suspension compress the extra distance available.

Shorter stoke? You don't want to slam the stops so you need a stiffer spring that will slow compression quicker. 

 

 

 

 

 

 

[Hollybrook]

And if you make any significant spring changes, you will also need to change dampening to match. That could be as simple as clickers, or you may need to change shim stacks.

[Tenerider]

12 minutes ago, Windblown said:

 

Spring rate is usually the same (or very close) for a given bike/rider regardless of the brand of suspension and even between two different bikes of the same weight - but only if the suspension travel is the same and the shock linkage ratio is the same.  If the suspension travel or linkage ratio changes all bets are off.

 

If you increase the suspension stroke then lighter springs should be used, decrease the suspension stroke and heavier spring should be used.  The reason for this is that you want to use the suspension available without crashing into the stops.

Longer stoke? You want to be able to make use of it so you'll need lighter springs that let the suspension compress the extra distance available.

Shorter stoke? You don't want to slam the stops so you need a stiffer spring that will slow compression quicker. 

 

 

 

 

 

 

Thanks, I agree in general - but you might also make use of the longer stroke by reducing comp damping, allowing for a more supple ride, and using the additional travel to create more rebound force, which compensates for lesser comp damping at the end of the stroke. Does that make sense? It's not yet second nature to me, I find it difficult sometimes not to mix up the position-dependant effects of springs with velocity-dependant effects of damping. Of course both forces add up, but anyways...

[Hollybrook]

@Tenerider If the compression dampening is too low relative to the rebound, the forks will not rebound fully in chatter bumps and the front end will dive, reducing available travel.

[Tenerider]

8 hours ago, Hollybrook said:

@Tenerider If the compression dampening is too low relative to the rebound, the forks will not rebound fully in chatter bumps and the front end will dive, reducing available travel.

Yeah, I know about packing, but I was thinking about something else when I said "rebound force" - meaning the "expansion force" generated by the compressed spring.

Comp damping slows down/limits the compression stroke by generating a velocity-dependent force in the upward direction.

The spring gets compressed and generates a position-dependent force in the upward direction, also limiting the compression stroke. Although they are completely different in nature, both forces add up and act against bottoming.

 

The question is, on a bike with more suspension travel (compared to OEM travel):

1. Would you keep the same spring rate and rather reduce comp damping, so the additional suspension travel can be used?

2. Or would you go to lighter springs (as @Windblown suggested) and keep comp damping in the same range, again to make use of the additional travel?*

 

I think both ways would actually work if we're only considering resistance against bottoming.

But I wonder what's the difference in actual bike feel, especially regarding "plushness".

 

Will the stiffer spring with less comp damping feel "better", or the softer spring with more comp damping? Obviously, this highly depends on the terrain you ride.

 

I can safely say on braking you'll have less front dive with the stiffer spring.

But I'm not sure about the general "feel".

 

*I know, you never should just use the same damping settings as before when changing springs, but I hope my point is clear: You need either more comp damping or a stiffer spring with less suspension travel to resist bottoming.

 

Edited March 16, 2023 by Tenerider

[Windblown]

7 hours ago, Tenerider said:

Yeah, I know about packing, but I was thinking about something else when I said "rebound force" - meaning the "expansion force" generated by the compressed spring.

Comp damping slows down/limits the compression stroke by generating a velocity-dependent force in the upward direction.

The spring gets compressed and generates a position-dependent force in the upward direction, also limiting the compression stroke. Although they are completely different in nature, both forces add up and act against bottoming.

 

The question is, on a bike with more suspension travel (compared to OEM travel):

1. Would you keep the same spring rate and rather reduce comp damping, so the additional suspension travel can be used?

2. Or would you go to lighter springs (as @Windblown suggested) and keep comp damping in the same range, again to make use of the additional travel?*

 

I think both ways would actually work if we're only considering resistance against bottoming.

But I wonder what's the difference in actual bike feel, especially regarding "plushness".

 

Will the stiffer spring with less comp damping feel "better", or the softer spring with more comp damping? Obviously, this highly depends on the terrain you ride.

 

I can safely say on braking you'll have less front dive with the stiffer spring.

But I'm not sure about the general "feel".

 

*I know, you never should just use the same damping settings as before when changing springs, but I hope my point is clear: You need either more comp damping or a stiffer spring with less suspension travel to resist bottoming.

 

 

 

Take a 10lb spring and push on it. It compresses easily. Take a 100lb spring, it doesn't. Which is going to absorb the force of an impact on one end with less felt impact on the other providing the impact is not enough to completely compress the lighter spring?  It will be the lighter spring.  That's way over simplified but with damping removed from the equation it is the correct answer.  Softer = plusher.

 

You can take a light spring and crank up the preload to get the sag right but you wont get nearly as much increase in effective spring rate at the bottom of the stroke and may bottom hard.  You can use a heavy spring with no preload but if heavier than needed you will transfer more energy into the chassis and rider than necessary everywhere in the stroke.   You have to have enough spring rate at the bottom of the stroke to put the brakes on the suspension movement in controlled manor.  Any more though is just stiffening the suspension in ways that don't help. Yes, damping helps, but as you mentioned, damping is speed related. As the suspension speed slows damping becomes less effective, and what is happening to the suspension speed right before it develops enough opposing force to stop compression?   Bingo - it's moving slowly and the spring is doing the work.  You have to have enough spring to do the job.

 

Back to your question...  Let's say you have a 200mm stoke suspension that provides the perfect amount of bottoming resistance. You now increase that stroke to 250mm and use the same spring rate with a 50mm longer spring.  First off - Your sag is going to be off ( unless you were running a lot of preload before and can take it out.  Secondly, your spring force will ramp up much higher than it did before as the suspension nears max compression because the spring is the same spring rate but is longer and being compressed further. Your gain is limited to an increase in bottoming resistance, and no gain in comfort up top. The thing is you didn't need that additional bottoming resistance if it was already good. 

 

Let damping do what damping does, let the spring do what it does.   

 

If you want maximum plushness and don't need much bottoming resistance use a light spring, crank up the preload to get sag right (it will ramp up less at is compresses) and control the wallow with damping. 

 

If you need a lot of bottoming resistance use a spring that gets you in the right ballpark with as little sag as possible. (it will ramp up more as compressed) and add in only as much damping as needed to control the spring. 

 

Man, I sure rambled on and half of it is probably BS. I'm no suspension guru. lol.

 

Edited March 16, 2023 by Windblown

[Hollybrook]

My philosophy on this is that if you increase travel, the best option is to select a spring rate that gives you the desired rider sag with little to no preload, and then adjust the dampening to match the spring and terrain. Just doing one or the other is not optimal and hopefully only a step towards a final solution. 

 

One of the main benefits I have found with the Rally Raid open cartridges is the much improved hydraulic bump stop.  The stock one was harsh, yet I still bottomed out the suspension (but with stock internals).  I have gotten into the RR bump stop, but never bottomed out.  But more important, I never felt the bump stop because it is more progressive.

[Windblown]

I think we're basically saying the same thing.  Get the right spring first, then adjust damping as needed.  The right spring is still a variable though. Stiffer spring / less preload or softer spring/ more preload - both work.  Just depends on the effect one is looking for. 

 

The majority of factory setups come with softer springs and a lot of preload. It's not because factories are dumb and it's not because it's cheaper. It's because it makes for a nice soft ride thru the suspension stroke at the cost of less bottoming resistance. If the bike is not being pushed hard bottoming resistance is not a factor, and most bikes are not pushed hard. 

 

The majority of after market off the shelf performance set-ups use stronger springs with little preload as it offers the widest range of spring force within the limits of the suspension travel. The result if set up right is a firm but controlled suspension. It's not going to feel soft and comfy when not getting pushed hard though.

 

Neither way is better or worse by default, just different with different goals.  Toddle along slowly with a standard suspension designed to be ridden hard and it will feel overly stiff.  Ride a standard "comfort" suspension hard and it wallow, bottom, and become dangerous due to lack of control. 

 

Or spend a big money and you can get a suspension that widens the range in which it works well and get closer to having the best of both worlds, but it ain't cheap... 

[Tenerider]

Thanks you two!

[Hollybrook]

@Windblown we are definitely saying the same thing.  You just included way more details and I oversimplified!  

 

I think one aspect of the suspension than many overlook is what happens when you bottom it out, and if you ride hard, you WILL bottom it at some point.  I feel like Rally Raid knocked it out of the park with their hydraulic bump stop implementation and wanted to point that out.

[Windblown]

6 minutes ago, Hollybrook said:

@Windblown we are definitely saying the same thing.  You just included way more details and I oversimplified!  

 

I think one aspect of the suspension than many overlook is what happens when you bottom it out, and if you ride hard, you WILL bottom it at some point.  I feel like Rally Raid knocked it out of the park with their hydraulic bump stop implementation and wanted to point that out.

 

Bottoming cones and top-out springs are a godsend for sure. Kills that nasty metal to metal "bang".

[Hollybrook]

41 minutes ago, Windblown said:

 

Bottoming cones and top-out springs are a godsend for sure. Kills that nasty metal to metal "bang".

 

From what I understand, the Yamaha cone is more like a cylinder, so when it goes into the cavity, the transition is abrupt.  That makes sense based on what I have felt with the stock suspension, kind of like a double bump when bottoming out.

[Windblown]

19 hours ago, Hollybrook said:

 

From what I understand, the Yamaha cone is more like a cylinder, so when it goes into the cavity, the transition is abrupt.  That makes sense based on what I have felt with the stock suspension, kind of like a double bump when bottoming out.

 

Yes. Same principal found in WP open chamber forks.  The effect is tunable by removing or adding bleeds.  I don't mind feeling them transition to the hydraulic stops.  Warns me I'm getting close to really pissing of my wrists.

 

[Jason]

Can anyone offer some guidance. I finally got the correct spring length but my mechanic just sent me a video of the fork leg back together and it sounds like the spring is just shaking around in the fork leg. He sent a video but it appears I can’t post it here as the file is unsupported. Is it because I have 0 pre load set on the fork? Surely there should be some sort of tension on the spring even without preload?

 

looking forward to hearing from you guys and hopefully it’s something simple. I’ve reached out to both Tractive and the retailer I ordered from and just waiting to hear back from someone. 

[Tenerider]

1 hour ago, Jason said:

Can anyone offer some guidance. I finally got the correct spring length but my mechanic just sent me a video of the fork leg back together and it sounds like the spring is just shaking around in the fork leg. He sent a video but it appears I can’t post it here as the file is unsupported. Is it because I have 0 pre load set on the fork? Surely there should be some sort of tension on the spring even without preload?

 

looking forward to hearing from you guys and hopefully it’s something simple. I’ve reached out to both Tractive and the retailer I ordered from and just waiting to hear back from someone. 

You got it: The springs need at least a few mm preload.

Usually, one plastic spacer is the minimum, to be fitted between fork cap and spring. This provides initial preload so that the spring doesn't wiggle around and prevents direct metal-to-metal contact between spring and fork cap.

[Jason]

23 minutes ago, Tenerider said:

You got it: The springs need at least a few mm preload.

Usually, one plastic spacer is the minimum, to be fitted between fork cap and spring. This provides initial preload so that the spring doesn't wiggle around and prevents direct metal-to-metal contact between spring and fork cap.

Gent, cheers man and that’s exactly what he did. Got the bike back now and feels way better. Can’t wait to get it on the trails now to experience the difference 

[Tenerider]

Ok guys, I finally got things sorted and couldn't be happier. Here's the whole story

 

At first, massive thanks to @r1superstar - your hint regarding tire height affecting trail in this thread here  https://www.tenere700.net/topic/6447-fork-position-in-triple-clamps/?do=findComment&comment=72585

was a breakthrough for me.

 

I changed my suspension to Tractive closed cartridges/rear shock a few months ago and recently moved from stock tires to Anakee Wilds.

 

I was never too happy with the performance of the fork cartridges, because no matter what I did on the clickers, they felt quite harsh to me. At first, I had way too much oil in them, but even after setting the air gap correctly it didn't deliver what I expected.

 

When I changed tires things felt even worse - I blamed the Michelins at first and thought they were just "harder" than the STRs.

Additionally, they felt quite unstable at higher speeds above 80-90 km/h. Lower speeds where fine, and the bike felt exceptionally agile.

 

Thanks to @r1superstar 's explanation, I now suspect a taller rear tire (bigger radius) to be the cause for the instability at higher speeds. The raised rear would actually decrease trail on the front wheel, making the bike more susceptible to headshake.

If this is true, solution should be easy: Raise the front, effectively lower the steering angle and thus increase trail.

To double-check my theory, I had a deep look into the Race Tech suspension bible, which - at least from my understanding - confirmed my theory 100%.

And they named a lot of different parameters which can be tuned to alter trail. Apart from lowering the fork legs in the triple clamps, more fork preload would also increase trail...

 

I had already noticed before that my static sag was rather high, more than 20% of the total travel. Since the sag with me on top was around 30%, I thought it to be ok but always thought about adding more preload. My suspicion was this might somehow make better use of the suspension stroke and remove the harsh feeling. I had no real reason to believe this though.

 

So I removed the fork caps and added a whopping two 5mm spacers

In theory, this should raise the front by 7mm (since I've had 3mm preload set on the caps before, which I've now turned down to zero). Quick measurements after installation confirmed it.

 

The test ride was a blast. Finally, the forks just cancelled out even the smallest road imperfections, they now felt almost too plush and where even wallowinga bit in the corners. Both easily amended by increasing comp and rebound damping by one click each.

Higher speeds felt safe again (although I haven't yet gone past 110 km/h, I avoided the Autobahn today) - the unstable feeling has gone as far as I can tell now.

The bike tracks very well now, stays planted also on rough, bumpy corners and is much more comfortable.

 

My current explanation for added comfort although I've ADDED preload is as follows:

With too much sag, the air spring comes more into play- and due to its progressive nature, makes the front feel firmer. Since I've now extended the forks, they seem to be operating more in their "sweet spot".

My dealer had pointed out before that the air gap on those cartridges plays a bigger role than one might think - even though the damping takes place in the pressurized cartridge, the air spring still adds progression. Interestingly, Touratech recommends a 10mm bigger air gap than Tractive - causing the the air spring to be much less effective, which again would increase plushness.

 

This is an unproven theory which might explain what's going on. But more important for me is the much better overall performance of the whole system. I finally feel I'm getting what I've paid for from the forks.

Edited April 9, 2023 by Tenerider