Ok I'm getting ready to order some lowering shocks. I have looked at many different brands and searched different HD forums. I'm wanting to lower the bike an 1 to 1 1/2 inches. Will the 11in Progressive 412HD's be good for me and passanger?

Does anyone have these shocks on there Dyna Super Glide?

I just want to make sure I'm doing and getting the right parts.

 

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Half the forum probably has these or another Progressive shock on their bikes. If you ride 2-up frequently, the heavy duty 412s (or the 440s) might be a good bet. Email Progressive, they can make a good recommendation.

 

The 412HD are for loads over 225lbs, the std ones are for loads under 225lbs. This includes the driver....so the advertisement says.

I personally like the 412HD covered chrome myself. (# 4 or 5 on "the" list)

 

"this is from an old post"

Don’t get me wrong the Progressive shock company makes one of the best quality products out there, no question.
And this is not to bash them.



I see a lot of chat & recommendations about progressive shocks but I wonder if every body knows what progressive wound shocks are all about? And how they react in BUMPY corners.

Anybody know what Progressive & Linear means when we talk about shocks?


And I know that almost every High performance part has the warning that they are for “track use only” or may not be legal in some states, blah blah blah.

But does any body know how “progressive” wound springs react over bumps in corners or in a skid or god forbid all 3?

You should before you spend big bucks on shocks.

It seems a lot of people buy Progressive shocks without knowing, that the name implies the type of winding & what different shock windings do.
Or at least my friends do.

You must take into consideration spring diameter, tolerances & windings when setting up a new suspension. Also keep in mind the difference the compressed shock under weight or the “bound”, and the shocks ability to extend or “rebound”.
Also important to most of us in the 1st place is ride height.


Linear springs are stock in most HDs and have a constant shape to the winding.
They are mostly comfy & cushy if long enough & balanced. The key word is “long enough” or as we see it ride height. This is why Electra glides ride so soft.

Progressive spring windings are wide on one end and close together on the other.
They are by nature a lot stiffer if not long enough (for us at least because most HD progressive shocks are shorter to lower our bikes & that’s the problem)

Shorter & progressive wound means a lot stiffer.

Not a problem if you are heavy or ride 2up a lot.

But for light weight riders it can make your bike feel like a hard tail.

If you lower your bike you will need a heavier spring /bound weight to avoid bottoming out.

Since HDs have a limited range of travel, sometimes after lowering a bike you can simply adjust the shock with a spanner wrench to increase the bound weight & reduce the un-sprung mass
(On Softail’s this will also ride stiffer but will maintain even spring rate & bike control.

In short;

Linear springs are constant. The weight travels from front to back & side to side and most important shock to shock smoothly & consistently.

It is easier for a rider to predict the rate of linear springs & there fore handle bumpy cornering emergencies a lot easier. I said bumpy!!!

Progressive wound springs increase rate as they compress or “bind”.

“Progressive” wound springs transfer force a lot more un-evenly from shock to shock in a bumpy corner than linear springs. Witch requires a lot more skill to maneuver & get used to in an emergency.

But who has time to get use to uneven spring rate in a bumpy corner in an emergency?

That is why progressive wound springs belong MOSTLY on the track. Where there are no bumps.

Progressive wound springs will also give you the most traction vs. power transfer loss in acceleration.


Just an example
Look at the current dirt bikes they have no ride height issues, they now have one huge (long)
Progressive shock, if they had 2 they would be all over the place.

Before you bash me to much you progressive lovers, take note of how many times I said “mostly” to c.m.a

Of course this will not pertain to all but “most” ha ha ha…

Just wanted every one to know because

Most dealers/suppliers will sell us anything without pointing out the dangers or benefits.

So I will go as far as to say if you never plan on encountering a bumpy corner or never going to have to react in an emergency in one, go ahead and put progressive wound springs on.

and yes this goes for front shocks to.
lot of people love them, but Progressive is not just the name, its the type of spring, thats all i'm sayin

 

I have 11" ones. Do not like. Poor ride quality over stock. They barely have any travel. The 12" shocks will lower your bike almost an inch and maintain a nice ride quality. If you can afford it I would recommend getting 11.6" or 12.1" works performance shocks. Best thing you can do for your suspension for the money.

 

I went from 12.6" stock to 12" 412 HD's and am very happy with the difference in ride and handling solo and 2-up. Going with 11"ers though may be a different story.

 

First of all I understand the difference between a "progressive" and a linear wound spring.But Progressive is also a name brand and I doubt their rear shocks are progressively wound.I use thier 11" 412 HDs and think the ride is fine for a lowered bike.You will have to play with the adjustment for awhile before you get comfortable.I also have their progressively wound front springs and am plenty happy with them.I have another bike with Racetech straight rate springs and cartridge emulators at three to four times the cost and do not see a huge advantage in ride quality or handling over the Progressive springs.

 

Thanks guys. Looks like I need to call some of these companies and see what they reccomend. What I don't understand is I measure the rear shocks from bolt hole to bolt hole and I come up with 12in with the bike standing up and nobody on it. I'm no dummy when it comes to working on cars, trucks or bikes. I have built plenty of 9 seconds cars. Is this the right way to measure or do I need to measure the shock off the bike?