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Mountune says their Sport springs are Linear

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#21
I wouldn't mind a slightly better ride, but I'm not about to lower the ride height.

I'd be scratching plastic in no time around here.
Ummmm no, you won't (as long as you are not an idiot)... I drive in Toronto and park in a condo garage with steep slopes.

I was in the same boat as you once, but then I realized life is to short to worry about scrapped plastic. It's a fiesta not a ferrari....
 


OP
SirThomas88
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Thread Starter #23
What are you saying exactly?
You can see both springs have a constant distance between the compression springs. This means they are linear
I really don't think you actually need this explanation to understand what he meant, but since you keep insisting on it, here goes..

A cursory look at the photo you provided makes it readily apparent why the rear spring would appear to be progressive to Dpro, XR650R and myself whereas the front spring appears to be linear. This is because there is a very obvious difference in coil distances seen on the rear springs whereas the front springs don't have this visible difference. I am certain that you can also see this difference yourself.

Dpro was referring to this difference in coil distances on the overall spring, which do make the springs appear to be progressive rate if you look at the entire spring as a whole rather than only look at the compression coils. On the other hand, FORZDA 2 is referring specifically the compression coils portion. So Dpro said that technically both he and FORZDA 2 are "technically" correct, he meant that although yes, functionally the rear springs are linear, this visible difference between the coil distances in the spring as a whole is itself a form of progressive variance, even though functionally and practically speaking, once installed the spring will act entirely linear and should be considered as such.

Your initial comment about coil distances and linear v progressive springs was helpful, but FORZDA's followup clarification was a much more helpful to the discussion, because unlike in your comment, he described the difference between the compression coil and the dead coils, and once he provided that clarification, Dpro agreed with it right away as he should have.

Fordza is spot on imo. Dpro is saying something else. We now await a response from Dpro.
So, Yes FORZDA 2 is spot on, but No, Dpro is not saying something different, for all the reasons I stated above. In fact, Dpro literally acknowledged that FORZDA 2 is correct and that he agrees with it. It's your understanding of Dpro's message that is incorrect, in which you have to completely disregard parts of Dpro comments to come to that conclusion.

No, there's no need to await a response from Dpro.. I'm certain you already understood what Dpro was trying to say just fine. It seems that rather than try to avoid an argument by simply clarifying the difference between compression coils and the dead coils as FORZDA 2 did, you're instead claiming there's a disagreement between Dpro and FORZDA 2 when its fairly clear that there isn't, and then insisting on further explanation when it's neither necessary to understand what Dpro meant nor helpful at all to contributing to the discussion at hand.
 


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M-Sport fan

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#24
Ummmm no, you won't (as long as you are not an idiot)... I drive in Toronto and park in a condo garage with steep slopes.

I was in the same boat as you once, but then I realized life is to short to worry about scrapped plastic. It's a fiesta not a ferrari....
One might be fine on merely rough roads, and steep driveways/speed bumps, with all of these lowering springs/slamming coil over kits, but just try hitting some of the craters, compressions, washouts, ruts, and huge 'baby's heads' on rough rally stage roads, and you WILL BE doing much more actual mechanical damage than just 'scraping plastic', even with a good skid plate. [:(]
 


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#25
One might be fine on merely rough roads, and steep driveways/speed bumps, with all of these lowering springs/slamming coil over kits, but just try hitting some of the craters, compressions, washouts, ruts, and huge 'baby's heads' on rough rally stage roads, and you WILL BE doing much more actual mechanical damage than just 'scraping plastic', even with a good skid plate. [:(]
Is your car lowered?
 


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#26
I really don't think you actually need this explanation to understand what he meant, but since you keep insisting on it, here goes..

A cursory look at the photo you provided makes it readily apparent why the rear spring would appear to be progressive to Dpro, XR650R and myself whereas the front spring appears to be linear. This is because there is a very obvious difference in coil distances seen on the rear springs whereas the front springs don't have this visible difference. I am certain that you can also see this difference yourself.

Dpro was referring to this difference in coil distances on the overall spring, which do make the springs appear to be progressive rate if you look at the entire spring as a whole rather than only look at the compression coils. On the other hand, FORZDA 2 is referring specifically the compression coils portion. So Dpro said that technically both he and FORZDA 2 are "technically" correct, he meant that although yes, functionally the rear springs are linear, this visible difference between the coil distances in the spring as a whole is itself a form of progressive variance, even though functionally and practically speaking, once installed the spring will act entirely linear and should be considered as such.

Your initial comment about coil distances and linear v progressive springs was helpful, but FORZDA's followup clarification was a much more helpful to the discussion, because unlike in your comment, he described the difference between the compression coil and the dead coils, and once he provided that clarification, Dpro agreed with it right away as he should have.



So, Yes FORZDA 2 is spot on, but No, Dpro is not saying something different, for all the reasons I stated above. In fact, Dpro literally acknowledged that FORZDA 2 is correct and that he agrees with it. It's your understanding of Dpro's message that is incorrect, in which you have to completely disregard parts of Dpro comments to come to that conclusion.

No, there's no need to await a response from Dpro.. I'm certain you already understood what Dpro was trying to say just fine. It seems that rather than try to avoid an argument by simply clarifying the difference between compression coils and the dead coils as FORZDA 2 did, you're instead claiming there's a disagreement between Dpro and FORZDA 2 when its fairly clear that there isn't, and then insisting on further explanation when it's neither necessary to understand what Dpro meant nor helpful at all to contributing to the discussion at hand.
First of all I didn’t quote you. Secondly it doesn’t matter how far apart the the coils are on the rear springs. To be linear the distance has to be constant which they are.
 


danbfree

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#27
Appearance of coil distance aside, Mountune has always listed a set single number spring rate instead of a range like Cobb and Eibach do, that was the dead giveaway. Mountune is not going to post a set number if they weren't linear, that would piss a lot of people off if they sold progressive spring with a linear/set spring rate listed. So honestly not sure how the rumor started that Mountune was progressive, as just because Eibach makes all 3, Cobb is literally a rebranded Eibach (same progressive range listed for both) the Mountune is linear (single number spring rate listed.) I trust Mountune in this case over guesses on how it looks.
 


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#28
Not sure if this has been put in layman's terms, but the tightly wound coils in the Mountune rear springs are only there to take up the slack when the suspension is fully unloaded. (So the spring won't fall out) When installed, they are linear rate because those coils compress completely. BTW, I love my Mountune springs as a simple way to drop the car about 1" without sacrificing ride quality, or costing much.

Sent from my Pixel 2 XL using Tapatalk
 


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#29
Not sure if this has been put in layman's terms, but the tightly wound coils in the Mountune rear springs are only there to take up the slack when the suspension is fully unloaded. (So the spring won't fall out) When installed, they are linear rate because those coils compress completely. BTW, I love my Mountune springs as a simple way to drop the car about 1" without sacrificing ride quality, or costing much.

Sent from my Pixel 2 XL using Tapatalk
No. You are wrong. While compressed they still have differing rates in the rear. Get out your caliper set and measure.
When you compress a spring to its proper loading it doesn't change internally/molecularly.

Too many people on this thread are talking with no engineering or material science background.

Mountune springs = progressive in rear and linear in front

This is not directed at you @briandee, but the internet is full of idiots spewing "wisdom"
 


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#30
No. You are wrong. While compressed they still have differing rates in the rear. Get out your caliper set and measure.
When you compress a spring to its proper loading it doesn't change internally/molecularly.

Too many people on this thread are talking with no engineering or material science background.

Mountune springs = progressive in rear and linear in front

This is not directed at you @briandee, but the internet is full of idiots spewing "wisdom"
What makes the rear springs progressive?
 


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#31
What makes the rear springs progressive?
They are tighter wond at the top and loser wond at the bottom. You can see this in the Eibach springs which is the manufacturer of the mountune.
When compressed they look linear but if you measure the difference between each wind they are nominally different.

This would cause the materials at the bottom being closer to their yield strength than the top. This leads to the progressive spring rate because larger dips are absorbed by lower spring rate difference and the small higher frequency bumps being absorbed by the higher spring rate.

More people need to invest time into reading the valuable knowledge available on on internet, rather than relying people to feed it to them.
The USA seems to have a large problem with not solving their own problems though, so I can't blame you.
 


danbfree

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#32
They are tighter wond at the top and loser wond at the bottom. You can see this in the Eibach springs which is the manufacturer of the mountune.
When compressed they look linear but if you measure the difference between each wind they are nominally different.

This would cause the materials at the bottom being closer to their yield strength than the top. This leads to the progressive spring rate because larger dips are absorbed by lower spring rate difference and the small higher frequency bumps being absorbed by the higher spring rate.

More people need to invest time into reading the valuable knowledge available on on internet, rather than relying people to feed it to them.
The USA seems to have a large problem with not solving their own problems though, so I can't blame you.
The ass out comes out so easily on this car people don't realize that a slightly progressive rear spring would actually probably help keep the back settled a bit with it's unsophisticated twist beam. It sounds like it's not a bad thing and in fact may be the best of both worlds this way.
 


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#33
They are tighter wond at the top and loser wond at the bottom. You can see this in the Eibach springs which is the manufacturer of the mountune.
When compressed they look linear but if you measure the difference between each wind they are nominally different.

This would cause the materials at the bottom being closer to their yield strength than the top. This leads to the progressive spring rate because larger dips are absorbed by lower spring rate difference and the small higher frequency bumps being absorbed by the higher spring rate.

More people need to invest time into reading the valuable knowledge available on on internet, rather than relying people to feed it to them.
The USA seems to have a large problem with not solving their own problems though, so I can't blame you.
Mountune shows their rear spring rate as
144 lbs/in. A progressive spring would show multiple rates. I don’t mind feeding you 🇺🇸
 


felopr

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#34
When you see people spewing stupid wisdom is time to step away
 


M-Sport fan

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#36
Is your car lowered?
Nope, on FULL factory suspension/ride height until I can find an affordable/reasonable setup which lowers the car no more than a half or quarter of an inch, AT MOST, and has the travel needed to handle those gravel stage hits. [wink]
 


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M-Sport fan

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#37
No. You are wrong. While compressed they still have differing rates in the rear. Get out your caliper set and measure.
When you compress a spring to its proper loading it doesn't change internally/molecularly.

Too many people on this thread are talking with no engineering or material science background.

Mountune springs = progressive in rear and linear in front

This is not directed at you @briandee, but the internet is full of idiots spewing "wisdom"
Actually, it is little known that the same said "material science" can actually produce a spring which is in fact progressive rate, even though it appears to be a linear spring with evenly spaced coils. [wink]
 


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#38
Progressive springs show multiple rates due to different compression coil size and shapes. Mountune shows one rate due to the fact that their compression coils have the same distance between them and are the same size.
 


danbfree

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#39
Nope, on FULL factory suspension/ride height until I can find an affordable/reasonable setup which lowers the car no more than a half or quarter of an inch, AT MOST, and has the travel needed to handle those gravel stage hits. [wink]
Ksport Pro coilover kits have 0-2+" amount of adjustable drop amount while maintaining the full travel with 32 levels of dampening adjustment. I believe ISC is similar with a lifetime warranty and rebuildable shocks.
 


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