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Discussion Starter #1
For those who have installed the progressive springs on front or rear or both.
How well do they work comparied to stock?

Thanks
(I tried to seach for past info on this but found everthing but)
 

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I've done both front and back and they are a big improvement over stock.

However, I switched to Traxxion and they were a big improvement over Progresseive.

With Traxxion, you can get just the springs or the whole kit. Much more expensive for the whole kit, but worth every penny. Progressive are one size fits all while Traxxion gives you springs for YOUR weight.

www.traxxion.com

But if you don't need the best, you will be happy with Progressive.
 

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I did the fronts to progressive last summer. That helped get the front off the bottoming stops much of the time.
I did the rear to progressive this last weekend. (See pictures in "Rear Spring Tool" post). I have not ridden the bike enough to comment on the rear, but let's just say I have my preload set at 0 and I am damn glad I did not put any additional spacer in there with the rear spring as some have done. I weigh 190. I ussually ran my stock rear spring around 10 when riding solo. I have not ridden the bike yet with 400-450 pounds of total load on it, but I suspect a big improvment riding 2 up with gear.
I also suspect I may have hurt the overall ride/performance for solo riding. I have not yet measured the sag on the rear, but I am wondering if I can get enough sag even at 0 preload when riding solo. I am really glad I did not use an additional spacer with the progressive spring on the rear.
 

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I did both the front and back end. It was a world of difference to the better. You can feel the difference as soon as you get onto the bike. I am now changing out my progressive fronts for a new set of progressives. After 50,000 miles I think they are due for the change along with the fork seals, oil and putting in All Balls bearings. I would love to try the Traxxion, but I just can't justify spending that much money for the front end. Maybe if the bike was new or almost new.
 

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BlueWing said:
I would love to try the Traxxion, but I just can't justify spending that much money for the front end.
You can do just the springs. Traxxion costs about $125 which is more than Progressive, but not out of line. Give them a call. They'll give you the right size for your weight. Many have done just the springs and love them.
 

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ddking said:
BlueWing said:
I would love to try the Traxxion, but I just can't justify spending that much money for the front end.
You can do just the springs. Traxxion costs about $125 which is more than Progressive, but not out of line. Give them a call. They'll give you the right size for your weight. Many have done just the springs and love them.


AND if you upgrade later they give you credit!!!!...chuck..(for your springs)
 

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I was finally able to measure the sag, both front and rear, with the progressive springs.
Based on the dust line on the front forks, the total travel looks like 4.5 inches. I hear the total travel on the rear is about 4.1 inches.
Here is the sag data for me (195lb) riding solo.

Front:
Sag______Total
1.75"______ 4.5"

Rear with preload set at 0:
Sag_______Total
1.5"_______ 4.1"??

I am warming up to the rear spring, but it looks like I have run out of adjustability to increase my sag anymore on the rear since I am at the limit of adjustability (0 setting). 1.5"/4.1" = 36.6% so I guess this is reasonable. I must have had my stock spring sag too high since the rear feels higher now at 0 preload. I wish I had measured the rear sag before removal of the stock spring. It also looks like my front springs could use a 0.5 inch spacer to get the sag closer to 30% of the total travel since 1.75"/4.0" = 39%. I have not had a chance to really exercise the new rear spring since my only riding has been commuting to work.
 

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i can't say what the ride was like without the was like without the springs sice i bought the bike used with them, but i can say that i have never experienced the front end wobble that people talk about here. I don't know if the front fork oil weight was changed with a different weight either. I love the bike set up as it is and think it delivers a sporty ride even with just one rider (weight 210-225)
 

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Mr Yak (LOL)

also suspect I may have hurt the overall ride/performance for solo riding
.

Stock springs sag ridiculously high. You will experience performance as it should be riding solo... the reason you (and I) had to crank up the preload is because the sag was so excessive. You may want to pick up a notch or two of preload when 2 up and fully loaded with luggage.

Too bad you spent the time and $ putting in progressive on the rear shock. When you are ready to upgrade seriously consider the Traxxion revalve and matching spring.

The positive remarks on Traxxion on this site are 100% true. I have done 2 prior suspensions (other bikes) with Traxxion and am doing the wing this winter. Service and quality are unmatched.

For those considering progressive rate springs (which is what "Progressive" sells) - please use search and look up straight rate springs vs progressive rate springs.
 

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I am not ready to spend that much money yet, but some day I might.
The progressive rear spring is not really that progressive according to some measurements...
A Progressive brand spring is not necessarily a progressive rate spring....

Max McAllister said:
.......

I hope you don't mind if I chime in with some more info for you.

I can't say we have found anything wrong with the quality of the parts of the OEM Honda shock that could be changed to improve it. It is very strong and durable.

We have measured the stock steel bodied shock from many bikes with 100,000 miles or more, and have not found any wear inside of them. Most of the shocks we service still have the factory cross-hatch on the wall of the bore!

....

I have never seen an OEM shock with a leaking seal either. Not that it hasn't happened to someone, I am sure. But I think if you can put over 50,000 miles on a shock with no wear or reliability issues, then it will be hard to improve upon that standard.

.....

You want to have a spring that requires very little preload; this allows the ride to remain plush on top, and yet the spring will have enough rate to support the bike over big bumps and big dips, and with gear and passenger.

The Progressive 460 is modeled after the stock shock as well. (We got one in last week for testing). They do fit their shock with a stiffer spring, although you may be surprised by it's rate and function.

The Progressive spring is marked "1000/1200". This would lead you to believe it was progressive in rate from 1000 pounds per inch to 1200 pounds per inch.

Using two different digital spring rate testers, we found that their spring was quite linear and actually fell in the middle of those numbers, around 1100 pounds per inch. It should work pretty good.

For the techies, we measure GL shock springs by preloading them in the same manner the GL shock would at "0", and then compressed them 1" and take a reading, and then a second inch and take a reading. This is all the GL shock will ever move the spring until the shock bottoms.

The stock shock spring is 900#/in.

The Progressive spring was 1050# at 1", and 1120# at 2". We would call this a straight rate 1100# spring here.

....

8)
In hind sight, I was running to much sag while riding solo. I wish I had measured thesag and optimized it more.
Two up, I was maxed out at 25 and definitly had too much sag.

While the stock damping characteristics may not be ideal, the change in damping coefficient (lbf/in/sec) required to accommodate the change in spring rate is pretty small.

Nerds only for the rest of this babble....
To first order, assuming a constant damping ratio, the change in damping coefficient is only sqrt(1100/900) = 10.5%.
(second order single degree of freedom differential equation approximation). That change is a pretty small change in damping coefficient. In fact for a critically damped second order system (damping ratio = 1.0) the damping coefficient (c) is c=2*sqrt(K*M). A higher mass or a higher spring stiffness require additional damping from the shock to maintain the same damping ratio, but the increase only goes with the sqrt of the increase in spring rate and/or the increase in total load.
End of nerd babble...
 

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Can I assume the progressive rear spring is ok, wondering if the triaxxon rear spring raises the bike. At my max height with stock now. So with added triaxxon front springs, and possible progressive rear spring, would this be close to stock height ? Only see the whole reworked triaxxon rear assembly on site? OPEN to comments too?
 
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I installed fronts only about two weeks ago. Due to it being Winter up here, I've only ridden about 200 miles so far with the Progressives.

Before I installed the springs, I completely removed the forks and cleaned out all the old fork oil. I found the left fork oil to be very grey, almost black and the right fork oil was still red. At 17,700 miles, the fork bushings and seals were still in very good condition so I did not replace them. (I also disabled the anti-dive which when tested, was still working like intended.)

My first impression was that the ride improved greatly. Its smoother, less harsh over the rough stuff. I also just put new tires on, so I haven't had time to push the new front suspension in the twisties. The progressive springs were about a 1/4" longer than OEM, obviously wound differently and marginally heavier wire.
 

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Discussion Starter #14
What Blind Yak said..........
(What did Blind Yak say????)

Nerds only for the rest of this babble....
To first order, assuming a constant damping ratio, the change in damping coefficient is only sqrt(1100/900) = 10.5%.
(second order single degree of freedom differential equation approximation). That change is a pretty small change in damping coefficient. In fact for a critically damped second order system (damping ratio = 1.0) the damping coefficient (c) is c=2*sqrt(K*M). A higher mass or a higher spring stiffness require additional damping from the shock to maintain the same damping ratio, but the increase only goes with the sqrt of the increase in spring rate and/or the increase in total load.
End of nerd babble...
 

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leaddog11 said:
What Blind Yak said..........
(What did Blind Yak say????)

Nerds only for the rest of this babble....
To first order, assuming a constant damping ratio, the change in damping coefficient is only sqrt(1100/900) = 10.5%.
(second order single degree of freedom differential equation approximation). That change is a pretty small change in damping coefficient. In fact for a critically damped second order system (damping ratio = 1.0) the damping coefficient (c) is c=2*sqrt(K*M). A higher mass or a higher spring stiffness require additional damping from the shock to maintain the same damping ratio, but the increase only goes with the sqrt of the increase in spring rate and/or the increase in total load.
End of nerd babble...
He was blind, ad I will help him to see! :lol:

Hi Mr. Yak,

You are looking at "discount" and not "mark up"... :lol:

Going from 900 to 1100 pound spring is a 22% INCREASE in the NOMINAL of the spring rate. JUST the name.... that means nothing. In spring force, a 22% increase IS significant. It could barely be compensated for if you had an externally adjustable shock, which you don't.

If you compare those two springs, give each 1/2 of preload, and then compress them an inch and a half (bottom out on a GL1800), then you will have two inches of pressure; while the percentage change is the same, the resultant change in spring pressure is DOUBLE.

That means the damper is going to be severely underdamped given that much increase in pressure.

Don't know where you got all of those formulae, but the interpretation of this situation isn't correct at all.

:)
 

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Can I assume the progressive rear spring is ok, wondering if the triaxxon rear spring raises the bike. At my max height with stock now. So with added triaxxon front springs, and possible progressive rear spring, would this be close to stock height ? Only see the whole reworked triaxxon rear assembly on site? OPEN to comments too?
Max can answer more technically, but your ride height will be higher because there is less sag with stiffer springs (free sag)

I know I am willing to pay for a better handling rear (get your minds out of the gutter) , among other reasons, to make my wife more comfortable... revalving the shock to match the stiffer spring (no matter whose spring) will improve ride and handling - I think it's like $300 plus spring cost
 

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fatfender, im in the same boat. 17,000 mile and thinking of changing the oil out, so why not try new springs. Now wondering how much higher triaxxons rear unit keeps the bike? Hey max, if u read this, kick in an answer. or i will have to email ya LOL.
 

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Max McAllister said:
leaddog11 said:
What Blind Yak said..........
(What did Blind Yak say????)

Nerds only for the rest of this babble....
To first order, assuming a constant damping ratio, the change in damping coefficient is only sqrt(1100/900) = 10.5%.
(second order single degree of freedom differential equation approximation). That change is a pretty small change in damping coefficient. In fact for a critically damped second order system (damping ratio = 1.0) the damping coefficient (c) is c=2*sqrt(K*M). A higher mass or a higher spring stiffness requires additional damping from the shock to maintain the same damping ratio, but the increase only goes with the sqrt of the increase in spring rate and/or the increase in total load.
End of nerd babble...
He was blind, ad I will help him to see! :lol:

Hi Mr. Yak,

You are looking at "discount" and not "mark up"... :lol:

Going from 900 to 1100 pound spring is a 22% INCREASE in the NOMINAL of the spring rate. JUST the name.... that means nothing. In spring force, a 22% increase IS significant. It could barely be compensated for if you had an externally adjustable shock, which you don't.

If you compare those two springs, give each 1/2 of preload, and then compress them an inch and a half (bottom out on a GL1800), then you will have two inches of pressure; while the percentage change is the same, the resultant change in spring pressure is DOUBLE.

That means the damper is going to be severely underdamped given that much increase in pressure.

Don't know where you got all of those formulae, but the interpretation of this situation isn't correct at all.

:)

Yes of course the spring rate is 22% higher. What I said is that the increase in damping coefficient required to keep the same damping ratio is 10.5% higher. Those who have engineered vibration isolation systems for avionics or heavy machines or worked LRC circuits will see immediatly my observations and agree or disagree since they use these relationships regularly. I am not to concerned either way. Just providing food for thought or consideration.

After two minutes of searching in google, I found the exact equation I was utilizing on the bottom of page two. "sqrt" means "square root".
the required lbf/in/sec goes up with the sqrt of spring stiffness and or mass as shown on the bottom of page two. The paper is a student lab for engineering students at MIT. The paper also indicates how to get the desired transient response from a spring, mass, damper system.

http://ocw.mit.edu/NR/rdonlyres/Mec...CFF-087E-48C8-A251-43E13821CF98/0/prelab3.pdf

I do value you opinion Max and I also value that you help so many folks on this board with your technical expertise. Keep on sharing. :)
 
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GL03 said:
fatfender, im in the same boat. 17,000 mile and thinking of changing the oil out, so why not try new springs.
I did...I installed Progressive's front springs and am satisfied. I bought them for $50 from another forum member. That's less than half the cost of new Traxxion front springs ($125) and I wanted to change fork oil anyway. Since I've noticed a major difference in handling, I'll stick with this setup for a season or two.

If I find enough $$$ floating around, I'll go with the $1150K AK-20 Traxxion front cartridges and the $450 rear shock. For now, the Progressive springs will have to do. I don't believe (COULD be totally wrong here) that I'll see enough difference changing from Progressive front springs to the Traxxion springs, so I'll just wait until I have enough for the AK-20s. I know Max offers the upgrade incentive, but I'm good for now.
 

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I don't believe (COULD be totally wrong here) that I'll see enough difference changing from Progressive front springs to the Traxxion springs,
good question - depends on the spring rate and wether is a progressive spring or linear - I stand corrected that all "Progressive" brand springs are progressive rate - thanks Yak Man, you engineering devil :beer2:
 
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