1996 XR600R

In doing a fork swap and researching fork springs Race Tech's calculator said the 1996 XR6 came with .36 fork springs. That is unbelievable! It then recommended .498 springs for the bike based up on my un-geared body weight of 170 lbs. The forks I have on it now have .47.  Why such a drastic change? I would think the change in stiffness would also call for a big change in sag measurements.


So with the stock .36 ultra soft springs what was the factory recommended static and race sag?

And if I got to stiffer springs what should the static and race sag be set to?

racetechs CALCULATOR is bonkers I will never tire of saying this, its the dumbest calculator out there...

it said I needed .51kg springs and I weigh 180 with gear...

makes no sense, I asked on here and elsewhere if racetech actually rates there springs differently/higher and never got a definitive answer compared to say factory connection, pc, cannon etc..

in any case

88-90 forks had .38kg springs with a topout spring as part of the total spring length meaning the long spring by itself  probably was close to .40kg
91 and up had .41/42 depending on who you ask
xrl springs are .44kg( a cheap very good upgarde for those of us on a budget on xr600's that just need a little extra stiffness

Since you are doing a usd fork swap you cant base your kg/rate from your old forks to new forks

you acually have to search around for your year model forks, look what the riders say about the forks, and weight and riding style and compare that to your bike(add weight of xr600) and give or take a little extra

I have cr250r showa twin chambers forks and I have correct race and static sag beleive it or not on my 88xr600, SAG stats on USDS are more than the xr600 stockers, beleive it or not again!

I have not bottomed out and I have fantastic performance from them after a rebuild, new seals and nice fork oil...they are plush since they have medium oil level height...

I did however add a squirt of 10cc's of 10weight oil just to slow down the action just a bit

Since your weight is only 10lbs over what honda reccomends or sets up stock I would only recommend 1 SPRING RATE UP on your springs no matter WHAT forks you have

like say from .42 to .45kg. this is for xr600 springs

Look up what spring you have on your usds, stock then up 1 or so from there

Its a common misconception that you have to automatically respring and revalve USDS when doing a swap, thats wrong

for example the cr250r is a motocross bike, yes its lighter but its forks are designed to swallow and absorb MEGA JUMPS and hits...

they already come with much higher rate springs stock for stock compared to the plush xr600 forks...

apples to apples always

makes it easier

cheers

Currently I have some Ohlins forks on the bike with .47s. I've not been able to find anyone who can tell me definitively if I should go up, that's why I was utilizing the spring rate calculator for the stock XR forks. The Ohlins forks were off an XC/Enduro model Cannondale/ATK.

If I could just find out what recommended sag is for the XR6, then I could measure the .47 springed forks to see if they are where we should be.

I dont have my manual with me, but sag on te xr forks was minimal

something like 1.5 inches static and 2 or so race, in fact I remember some manuals didnt even give details on sag stats for the forks, only the shock!

the choppered out feel is part of this problem...

my usds albeit longer sagged more and turning and carving is a beauty now!

on stockers it was always push push push and fall,

the geometry if the bike is so much better now...

anyways...

my usds have 35-50mm static and 70-80mm race....per showa cr250r stats

whats your measurements now?

Edited by elsalvadorklr, 20 June 2012 - 05:55 AM.

I'm at 31mm static sag. Gotta wait for wife to help me balance to do loaded.

mikesbaron, on 20 June 2012 - 05:46 AM, said:

What El said, USD come setup much stiffer than XR's, so any XR advice is moot when talking different forks.  My CR125 forks are PERFECT for my riding, and I haven't even touched the adjustments.
Ride the bike awhile and play with the adjustments before you go making expensive changes.  JMO

Edited by MindBlower, 20 June 2012 - 10:45 AM.

My loaded sag is 72mm. I think the range should be 80-95mm. So I think I'll stick with these .47s.

well I think you are spot on for your bike with these forks, the extra weight of the xr will soak up the extra race sag you have left, its not PERFECT but you are very close to it

I think I have 85mm on my showas, which is at the maximum level, in other words If I gain 20lbs or so Id be undersuspended

Play aroudn and RIDE the bike a lot, and set the clickers and adjustments to STOCK ohlins settings that cannondale used on that bike

Play around in small steps, and see what  you like

Im a tinkerer so I added a bit of oil to prevent bottoming(havent yet) and I also went a little harder(4 clicks) on the compression clickers, and a little hard again(2 or so clicks) on the rebound...

just a bit since the bike is heavier than a cr, thats been working great for me so far...

havent bottomed out yet or bounced back up after a hard flat jump like I used to have happen with the stockers, when that happened I had the front end bounce way up after bottoming and the rebound COULD not control that bounce, it wa horrible...nothing like  good set of twin chambers and a revalved, rebuilt shock out back to take care of that!

jejeje

good luck

Funny enough what led me to look at harder springs (before I even checked my sag) was riding the bike for the first time with the recommended Ohlins/ATK/Cannondale settings. The thing had ZERO compressio or rebound on it with those settings.

well I learned that twin chambers at least react VERY much more when moving clickers, in other words they actually work quite well and do make a difference when playing around with them

on the xr forks, rebound only, you only felt a difference when one extreme to the other, what made more of a difference was good ole preload, spacers, oil weight changes etc..but thats a whole nother story for later ! jajaja

if its soift and pretty bland stock setting try one extreme at a time
go full hard on compression and see if it its slower to react on harsh bumps, or jumps, etc...

if so then go easier till its plush or compliant yet withstands the hits...

then dial in rebound only till you get comp setup or finished first...

see if you bounce too much afer landing or going over rocky stuff, you can usually slow it down enough to float over certain terrain but you cant have it all! you have to have a setting thats decent at everything unless all you ride is sand or enduro, or motocross, etc..etc...

if clickers dont do anything then an oil change and level height/volume increase is in order...

if that doesnt work send them to get revalved for your riding style and weight

Edited by elsalvadorklr, 20 June 2012 - 02:33 PM.

Umm, don't the stock XR forks have only a compression adjustment clicker and not a rebound adjuster?

I just put some slightly stiffer springs into my forks (stock 1989 fork main springs without the top out springs into 1999 forks).  Now the forks need more rebound damping to compensate for the stronger springs.  I guess I'll try some heavier viscosity fork oil before getting into revalving.

heart_of_darkness, on 15 July 2012 - 04:30 AM, said:

yes..I misspoke compression only...rebound is adjusted with oil weights and levels...

I have a thread with pics comparing the 88-90 springs to later year springs and the reason you can take out the top out springs or cut and add spacers to the 88 springs since they are coarser wound

in other words you can preload them more with out getting coil bind...they worked awesome on my 96 cartridge forks...very forgiving