SuzukiSavage.com - Print Page

SuzukiSavage.com
/cgi-bin/YaBB.pl
General Category >> Rubber Side Down! >> I want stiffer fork springs NOW!
/cgi-bin/YaBB.pl?num=1247331711

Message started by Rockin_John on 07/11/09 at 10:01:51

Title: I want stiffer fork springs NOW!
Post by Rockin_John on 07/11/09 at 10:01:51

Not some half-fast fix like a longer spacer! The springs in the forks on the 99 I'm riding most often lately (not the chopper) are sagging so bad I only have a couple of inches of rebound on them; then it's THUD as they bottom out!

I even tried swapping out the seemingly much better springs from the old 87 that I seldom ride, and they sagged too once installed on the 99... I really don't understand that one, as everything seemed to measure the same (except I had no scale to actually measure the actual spring rate of all involved):

http://catoosatrading.com/images/cycles/parts/savage_fork_springs.jpg

But why would the springs which stood tall in the 87, suddenly sag like the others when installed in the 99s tubes?

I'm tempted to use the old "stretch-the-springs" with a come-along trick I resorted to on my old Kawasaki dirt bike when I was a kid. As I recall, I stretched them too much (like 6") and had so much pre-load that I almost never got the fork caps pressed down to get the threads to catch.

There's got to be an easier/better way??? :-?

Has nobody ever contacted Progressive to see if they have something already in stock that we could substitute? Or would it require that they (or someone) be convinced to make a specific spring(s) for the LS-650?

Title: Re: I want stiffer fork springs NOW!
Post by bill67 on 07/11/09 at 10:23:01

DavidQuinnmotorcycles has hagon fork springs for the S40,I don't know why but if I remember right they said use 5 weight oil in the forks

Title: Re: I want stiffer fork springs NOW!
Post by verslagen1 on 07/11/09 at 10:51:44

If bottoming out is your problem then I'd put in thicker oil.

Did you change the oil when you swapped springs?

Some have said the oil viscosity drops after awhile.

general rule of thumb for springs

if it has the same wire diameter and the same number of coils... it's the same spring rate. Now you can have different preloads with different overall lengths.

Springs with less coils have stiffer rates.
Springs with larger diameter wire have stiffer rates.
Springs with less coils don't last as long.

Title: Re: I want stiffer fork springs NOW!
Post by Rockin_John on 07/11/09 at 11:05:23

02090C0C5657600 wrote:

DavidQuinnmotorcycles has hagon fork springs for the S40,I don't know why but if I remember right they said use 5 weight oil in the forks

Thanks Bill, I'll check into that!

Title: Re: I want stiffer fork springs NOW!
Post by Rockin_John on 07/11/09 at 11:12:45

544750514E4345474C13220 wrote:

If bottoming out is your problem then I'd put in thicker oil.

Did you change the oil when you swapped springs?

Some have said the oil viscosity drops after awhile.

Yup I made sure I had the proper amount of "fork oil" in them... But I went cheap and just put some Dexron ATF off my shelf in them. I've run expensive fork oil and ATF in the same forks several different times over the years, and frankly, I've never been able to tell much difference!

And this bike is sagging so bad I'd probably have to put 90w gear oil in the forks to keep them from bottoming! ;)

Title: Re: I want stiffer fork springs NOW!
Post by Rockin_John on 07/11/09 at 11:52:40

Checked into the Hagon springs on the web site. Looks like what with Pound to Dollar conversion and shipping, a pair of their replacement springs would be somewhere around $150 + That's a lot of money for springs on which they don't even give you a standard compression rating on (Like 90/120 etc...).

Title: Re: I want stiffer fork springs NOW!
Post by bill67 on 07/11/09 at 12:43:37

Heavier oil makes the compression stiffer than what it changes rebound must be smaller holes in the compression part of the damping.

Title: Re: I want stiffer fork springs NOW!
Post by bill67 on 07/11/09 at 15:15:54

You can make air forks out of your forks,You need a air valve for each of course,Drill and tap the fork caps and put the air valves in,somewheres between 6 and 8 pounds of air should do it,It only takes a little air it is a small chamber,You have to be careful or you would blow at the seals.I did that on my 1975 watercooled suzuki,I didn't need it I did it to see if it could be done.

Title: Re: I want stiffer fork springs NOW!
Post by thumperclone on 07/11/09 at 16:34:08

from your phpto you appear to be within the sevice limi of15.45"
any shorter then replace..
to refresh:
no scuffing on the inner tube sliding surface
no wear on the damper rod ring and oil lock piece,damper rod torqued to 18 > 25.5 ft lbs
use of oem fork oil seal installer(#09940-50112)
14.91 oz(441ml) #15 fork oil
ssm"when adjusting oil level,remove the fork spring and compress the inner tube fully"
"hold the front fork vertical and adjust the fork oil level with the special tool" (#09943-74111)
large pitch end of the spring on the bottom

hope this helps T.C.

Title: Re: I want stiffer fork springs NOW!
Post by Rockin_John on 07/11/09 at 19:01:52

2B372A322F3A2D3C3330313A5F0 wrote:

All seals appear to be in good condition as all forks involved contained an appropriate amount of oil upon disassembly. However, I used the "volume" method to get the correct amount of oil back into the forks, then measured the level once they were back in the trees. Seems they came out right on the money.

What really puzzles me about the whole thing, is that all the springs measure the same length. And of course when I switched them I expected the 99 to stand taller and ride more firm, as the 87 formerly had. This was not the case. Regardless of which springs were in which legs, the 99 sags, and the 87 doesn't. Just weird.

Title: Re: I want stiffer fork springs NOW!
Post by justin_o_guy2 on 07/12/09 at 05:20:34

Gold Bond Presents,,,,,, Newest Concept of Measuring Instruments...

Its a Yard stick, man, from When? For that to be "a New Concept" it would be a pretty old stick, now wooden it?

Title: Re: I want stiffer fork springs NOW!
Post by Charon on 07/12/09 at 07:15:36

Seems to me that if swapping the springs has no noticeable effect, something else must be different. Perhaps you need to find out what that is.

The springs carry the weight, regardless of the type of oil. Changing the oil viscosity, as Bill said, changes the damping but not the ride height. Adding a spacer simply precompresses the spring, or preloads it depending on your favorite terminology. The spacer may also reduce the total available travel by taking up room otherwise available for movement. From your picture, you already have some pretty long spacers installed (which look like electrical conduit, to me). Your fork travel will end when the coils of the spring are forced together, and preloading the spring reduces that available space.

Title: Re: I want stiffer fork springs NOW!
Post by thumperclone on 07/12/09 at 09:25:00

just a guess: have you compared the tripple trees?

Title: Re: I want stiffer fork springs NOW!
Post by serenity3743 on 07/15/09 at 05:08:06

4E5D4A4B54595F5D5609380 wrote:

If bottoming out is your problem then I'd put in thicker oil.

Did you change the oil when you swapped springs?

Some have said the oil viscosity drops after awhile.

Something I did accidentally that might help you. Once when I changed fork oil, I didn't read the manual and I filled the forks to the top UNcompressed. Used 15 weight oil. I noticed a really stiff front suspension. Are you sure your "taller" forks didn't have more oil in them?

Title: Re: I want stiffer fork springs NOW!
Post by Boule’tard on 07/15/09 at 06:54:51

Adding more fork oil as serenity3743 suggests is a pretty good idea (in moderation of course) and will definitely increase the air-spring effect without having to install Schrader valves or anything.

But I think the best way to go is to install some race-tech cartridge emulators. Those add a modest 1/2" of preload and allow you to dial in as much compression dampening as you want, and you can control the rebound dampening independently by the oil weight. I'm pretty sure the emulator kit # FEGV-S3801 works for the Savage's 38mm forks.. but check.

Title: Re: I want stiffer fork springs NOW!
Post by verslagen1 on 07/15/09 at 09:16:04

While messing with my steering stem I had the forks off.
When I redid the seals on the '96, the oil came up to just below the springs.
I looked at the '88 and the level wasn't near as high.
So either it leaked out (highly possible), wasn't filled correctly, or something is different.

So that gives us 2 possibilities for your problem, either the fluid is low or your caps aren't sealed. I'd add oil to the top of the springs and work from there. Adding a couple of ounces at a time and see how it feels. This will reduce the air volume a little at a time and do the same as adding air pressure to the forks. You'll still have the same issue with blowing out the seals if you exceed the capabilities of the seals. But adding a couple of ounces at a time will allow you to sneak up on it.

Title: Re: I want stiffer fork springs NOW!
Post by bill67 on 07/17/09 at 13:14:21

Dave Quinn E mailed me back they had to check the pounds on the s40 hagon fork springs they are 27- 43 pounds variable,So if S and W make a spring the right length and diameter close in that weight range they should work and be cheaper,hagons $143 plus shipping.