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Discussion Starter #1
I raised a question in another thread about the blessing given to progressive springs and thought I'd continue here for my own curiosity. It seems there is a belief that linear springs are "stiffer" than progressive and that does not make sense to me.

A progressive rate spring does not determine stiffness as I understand. You can have a soft light linear spring and a stiff progressive one for example. I'm no expert, but simply trying to understand why such a focus on Progressive front springs as the cure all, when my (limited) experience and most discussions I have had over time with suspension houses is they are an old solution to an old problem. As with many things, people can go with a common thought simply because it seems like a good idea, and it gets reinforced by more people following a suggestion. The standard set up is garbage so anything is an improvement so that may be where it was born from. I am just trying to understand why it seems to be promoted so heavily and maybe it is that it is the quickest/easiest/most cost effective fix. My research shows that for around A$800-$1K I can have the forks set up with good quality springs, valve emulators and preload adjusters and for what will be a keeper seems like a good investment. Then when upgrading to an "adjustable" rear shock, the front should also be capable of the same to get the optimum set uph.

Just interested in peoples thought processes.
 

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Progressive spring is stiff and smooth when needed, linear spring is a compromise. When you drive in smooth road progressive springs are smoother than linear (linear is stiffer). When you drive to bump or brake heavily, linear spring takes that hit, but stiffness is same all that time. Progressive springs goes stiffer in every inch and thus its better, front end doesn't dive and you feel better.
 

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Please correct me if I'm wrong but isn't the idea of a rear linkage & monoshock set up to achieve a progressive or rising rate suspension, beyond that possible with the limitations (spring length?) of twin shocks ? So maybe it's reasonable to assume there would be similar advantages for front forks?

FWIW:-

I have Hagon progressive springs & cartridge emulators fitted. They seem to offer a definite improvement in brake dive but I'm still trying to optimise things (learning how :confused:) for the cart tracks that pass for most rural Irish roads. The springs could be a little light for heavier/two-up riders, so as there are few prog. spring choices a stiffer fixed rate option might be better for some.

There's no doubt that the cartridge emulators work far better when hitting sharp/deep bumps in the road, but their instructions/guide could be far more helpful. The emulators affect compression damping only. From what I've learned so far, you want this at the minimum you can get away with for good 'compliance', possibly going less than their suggested 2 turns 'base' setting. Rebound damping can only be adjusted by changing the grade of oil & here it's the opposite - better to err on the higher (more damping) side. When the weather improves I plan to try going to a heavier 15W oil.

IMO the standard rear shock has too much compression damping & no where near enough rebound damping. The spring rate seems adequate for my (light) weight, but would be way light for heavier/two-up riders. I've a ZX9R adjustable shock on the way & will post up the results in due course.
 

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The argument between progressive rate and fixed rate is easy to understand: Whoever spends the most has the best bike.

Compare the discussions here over the addition of inexpensive Progressive springs versus "The Full Race-Tech Suspension Treatment."

That's especially important where the difference cannot be proven.:rolleyes:

Jim
 

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Discussion Starter #5 (Edited)
I think there is some confusion here. Spring stiffness (or reduction of) is not achieved simply by going to or away from linear or Progressive. That would be achieved by going to a lighter or heavier spring. A progressive spring would change the rate but not the stiffness as I understand if the springs themselves were comparable in stiffness. You could have a heavy Progressive spring and a light linear for example. I also understand that the amount of air space left has a bearing on the progressive nature of how the fork compresses.

My question is specifically why people mostly suggest a progressive spring when in most cases, a professional would recommend they are old hat. So it must be cost/convenience. No need to Ridicule those that chose to spend more on suspension. This comment amuses me as I am sure there are many that spend little on this aspect but don't hesitate on exhaust systems, chrome, leather and other customisation. It's a case of where you see the priority for your own benefit, should not be a case of he who spends more has the best bike. I'm trying to take the emotional side out and understand the practical nature of peoples decisions. I do this because I am close to doing the mods and trying to determine the best comprimise. I can spend A$1500 on a "professional" set up and it might be the bees knees, but there may be little point if by experience, a set of progressive springs and a 2nd hand shock will do it for less than a quarter of the price.

I ride solo, will do a track day here and there, but also cruise with my daughter pillion for a Sunday ride and tour with my wife. Adjustability is a key. So I am trying to qualify both a) if the suspension gurus are on the money or simply blowing smoke up my backside, and b) if progressive springs are chosen by the majority because they are the best outcome (regardless of cost) and qualified so, or simply that they are used as the quickest/easiest/most cost effective solution or that like me initially, I read it on a forum to be the fix for this model and simply assumed it as the best option.
 

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Magilla , i think you're confusing us with someone else . :) this ain't no gixxer bling group and i don't mean that in a condescending way . we love these bikes and make no pretenses about what they are and are not . most of us paid $5k or way less and would have bought a more modern japayamazuki if we wanted to .

$67 inc post for my progressive springs and 1000% percent improvement is a no brainer . to us anyway . $400 for a hagon or $1200 for a custom penske ?

hey knock yourself and your checkbook out . all's welcome here :)

<puts cloak over face and heads back to the vintage board ...
 

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The way I understand this is that progressive springs are usually better for the street, where you want a combination of reasonably good ride, but reduced front end dive under braking.

linear springs are usually better for Track use. where the surface is generally much better than the street, and ride comfort is not so much of a consideration.

It sounds like your intended use is somewhere between those two possibilities, So what will you use the bike for the most?

If you are a very aggressive street rider most of the time you might want linear springs for your street riding.

Riding style and where you ride. The springs themselves are relatively inexpensive so maybe try what you think is best first, and if it has shortcomings they are not so difficult to change, and only costs you a little time if you do it yourself.
 

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Discussion Starter #8
Woody, I'm sure it's all tongues in cheek here but rather than answer a question it seems some of you are more intent on defending your choice rather than giving an objective view.

Not that it is important, but this is my 5th modern Triumph in 11 years. I have had a Sprint ST, 2 Speedmasters (1 I built into an outfit), and this is my 2nd Legend with a 5 year gap following a regret selling the first and a 2 year search for a replacement. With the A$ conversion I paid about what you did. This is also the first time I am considering spending anything on suspension and see it as a justifiable investment over most other mods.

And no this isn't no Gixxer Bling group, but a good look through the pictures threads suggests there is a fair amount of Triumph bling going on, and what's wrong with that? Horses for courses. I am simply trying to determine "why" progressive springs are more widely used and it seems the answer is clear. It "is" a cost issue more than anything else as those that chose that path did so by discounting other options because of it. So thanks for answering the question if not in a round about way. :)
 

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hey Magilla , tongue in cheek aside , $67 turned my wallowing beast into a sweet ride .

please don't take things the wrong way . good bunch of folk here :)

i ride the local constantly dug up and poorly repaired streets one up no track days streets .

the progressives give an easy ride when you're just cruising but the needed extra when you need it . it's that simple .

cheers , Woody
 

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I want more bling,more speed and a quality suspension set up for as little money as possible!
I spent a zillon dollars on my ohlins shocks and emulated front suspension on my last last project (Harley sportster) and it handled very nicely indeed for a sportster.A friend with the same model had progressive front springs and ancient rebuilt konis costing $300 total and was a sweet handler also,with little in it between bike's when jumping one from the other.
This time I am going cheap first!
 

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If you read my posts in the "cheap suspension upgrade" thread, you'll see all of the details of the rear shock upgrade I did, following Greg's lead. The one downside to the upgrade is that it still is not quickly adjustable for carrying a passenger. I played around with different settings for awhile until I got it to its' best setting for me personally, but it would need to be tweaked for 2-up long distance stuff. If you can afford to get one with dial up preload adjustment, I'd say spend the coin. Even though the zx-11 shock was a huge improvement over stock, this lack of preload adjustability definitely makes it less desirable for someone who rides both solo and 2-up frequently. As for the progressives, at such a low cost, why not try them and see if they are satisfactory? Should be easy enough to unload if they don't please you, and then if you do go ahead and spend the big bucks on the race tech stuff, you'll never have to wonder how it compares to "plain old progressives". When you boil it all down, any suspension mods are attempts to improve the ride and handling, and there are so many variables that one person's perfect set-up might be awful for a rider of a different size, riding style or even locale. Only you can judge whether your bike handles the way you want it to, and if it does, your money was well-spent, no matter what the dollar amount. Just my 2 cents on a cold winter night (10 degress).
 

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Discussion Starter #12
Ok, this is good, some real world feedback :).

This is the deal. The majority here endorse a change to progressive springs for the front, play around with spacers for pre load and oil weight. Rear seems to be settled with an ebay shock for less than $100. Seems a fair investment made and a good result.

So I removed springs and spacers a few weeks ago, measured them up and corresponded with Icon here in OZ for a solution. At the other end, I talked to several "Professionals" whose opinion was progressives are a waste of money and linear with pre load adjustment and cartridge emulators could be had for a fair price (but they have a business to run too).

So my post was to try and understand why such unanimous support for a solution that was deemed old hat by the "experts". As I said earlier, they could well have been blowing smoke up my butt.

As a comparison, I used to own aprilias and the greater majority that I rode with insisted on the stickiest most expensive rubber and had their bikes kitted with Ohlins (that never saw a change away from out of the box settings). I was happy with sport touring tyres that cost a lot less and lasted more than 3 times as long and I was never penalised for handling, performance or grip. I also learnt to make the best of the stock Showa/Sachs setup. But, the general consensus was based on a perception that the sticker the better, when for road riding is was really unnecessary, and simply having Ohlins gear assumed it was the best even though no setup had ever been invested in. Sure, in the right hands and on a track it would make a difference but for every day riding, very little.

So I think I'll go order the Progs, start looking for a reasonable rear and thanks for the feedback!
 

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Magilla, now that you've quantified your question sufficiently for a rational answer, I'd suggest you go for the full emulator/single rate spring setup.

My reason for this is 'track day' and the need you will have to get every bit of 'edge' from the bike that you can.

Progressive springs are excellent for street riding. With proper setup (oil viscosity and spacer length) they will perform as well on the street as will the emulator/spring setup but lack the easy adjustability for fine tuning to track conditions.

Most folks simply want to cure 'braking dive' on these bikes (pretty horrendous when stock) and aren't about to push their bikes to the limit (their personal 'human' limits are a different issue) so progressive rate springs are much the better choice.

The choice of the emulator/spring setup will also allow you to adjust for tire composition and pressure changes that are usually more noticeable than a 'one click' difference in the suspension setup.

Jim
 

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Discussion Starter #14
Appreciate your input and ideas! However 99% of it's work will be day rides in the hills and touring, so the "adjustability" would be for the load differences of a solo 70kg rider, to 2 up with gear rather than fine tuning between sessions in pursuit of faster lap times. The track days are just for fun and maybe a couple a year, with no high expectations. Did one on a Speedmaster (with only rear pre load) and had as much fun as the one I did on a Tuono which was well set up. But a week touring with poor suspension is hard to live with.

So based on all the good feedback, I am going to go the Progressives for the front and spend a bit more on a good rear shock with remote preload and make notes from there which seems to be the benchmark here. Again I was just trying to understand why it was the case.

Thanks again for all your help and sorry if my line of questioning was a little vague or misguided.
 

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magilla , the hagon 's available w/ remote for not much more . under $500 US . if you can't find a local supplier call dave quinn .

cheers , Woody

ps also the person advising you to not bother with the progressives wasn't aware how horrendous the original springs are .
 

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Discussion Starter #16
Cheers Woody! There's a Hagon rep here in OZ. Looks like about US$120 for the springs and US$570 for the fully adjustable mono with remote preload.
 

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I'll be honest, I got front and rear progressive. Rear was a slight noticeable improvement. Front, with belray 15 w using the fol 2 tool for measurements, I can honestly say. Save your ****ing money!. Just put different weight oil in or try those emulators or something. I can't notice a blind bit of difference at all. No upgrade.
 

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I've been thru a lot of iterations in suspension mods (since my posts above), now using sport bike USD cartridge units with Racetech compression valves & rebound re-shimmed. This, with Showa ZX6R '08 rear shock, is night & day over a stock bike, & compares favourably I think with anything else on the road including current sport bikes. For my purposes, that is - quick steering, accurate & remaining composed over pretty rough tarmac, especially in corners, as is the norm here.

However, for stock forks & bang-per-buck, Ricor Intiminator valves can't be beaten imo, and without any other changes to the front unless the rider &/or pillion weight is high enough to warrant a spring change. To get the full benefit, the shock needs to be changed as well.
 

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Been through several iterations myself on different bikes. The seat of my pants have the opinion that correctly weighted linear springs are better than progressives provided your shock and forks work as they should - they don't need to be track standard if you're only riding on the road.

You cannot, however, fix a bad shock or forks by simply fitting better springs.

Just my opinion.
 
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