How can I tell if I have Progressive Springs in the forks?

[hpras]

Hi All.

The bike ('87 FJ) has the neato decal on the side cover, but does it have the actual springs.  Any way to figure that out?

Cheers

Hans

[mz_rider]

Hi All.

The bike ('87 FJ) has the neato decal on the side cover, but does it have the actual springs.  Any way to figure that out?

Cheers

Hans

Hans,

The Progressives on my '91 are shorter that the Yamaha items and use a spacer (about 70mm long) to make up the length. So a spacer would indicate Progs.

Stuart

[FJ Flyer]

Not necessarily.  I have straight rate springs with spacers.  Does he mean the Progressive brand, or progressively wound springs.  If its the latter, than the spring spacing will be tighter at one end.

[andyb]

The stock springs are progressively wound also.

Some of the 1100's used a spacer with the OEM's.

[hpras]

Progressive brand.  The spring are progressively wound however.  I was just wondering if maybe they stamped something somewhere I could look for the next time I have a forks apart.

[Tuxracer]

Progressive brand.  The spring are progressively wound however.  I was just wondering if maybe they stamped something somewhere I could look for the next time I have a forks apart.

I have a brand new set still in the box until I find time to install them, or get them installed since I really wouldn't have a clue how LOL. Anyway... I checked them over and there is nothing marked /stamped anywhere. I can measure them for you if you like

[SlowOldGuy]

The stock fork springs are a kind of progressive rate.  They have 2 distinct coil spacings.  The tighter wound spacing coil-binds first and the spring rate increases to the larger spaced value.  You can see the abrupt transition between the 2 spacings.

Progressive (brand name) springs are a true progressive wound spring.  The coil spacing goes from a small spacing (low rate) to a wider spacing (higher rate) progressively over the full length of the spring.  There is no distinct transition.  These springs gain spring rate as the coils bind up.

You can actually increase the rate of a Progressive spring by cutting some of the tigher would coils off and installing a spacer.

DavidR.

[pdxfj]

Here's a comparison of an aftermarket straight rate spring (top) and a progressive wound spring (lower) that would be similar to what is in the stock FJ forks.



Then what the "Progressive Suspension" springs look like.

[Tuxracer]

They measure 18" long with the tighter section being 3.5"

[SkyFive]

I have my 1984 FJ1100 springs out, they measure 15" with the tighter section being 3.5".

[hpras]

I think we have it then.  I have Progressive (TM) springs in my FJ.  The tight coils are only a small portion of the entire length as opposed to the pics of the stocker where they are half.

Thanks all

Hans