fork settings

[Tom]

G'day all im putting new seals in my 125's forks i want my forks to be fairly stiff but not quite sure how to set them up.The standard settings in the manual are OIL CAPACITY- 415cc - 199mm and the air pressure is MINIMUM-4.3 psi and the max is 15psi so whats a way i can set it up 2 make it stiff as?? any help much appreciated Tom

[Freakshow]

Stiff on compression stroke or stiff on preload ?   IF you want a quick fix to slow it down run thicker wieght oil, if your a 10w try 15 or 20w.  OR mix up all the bottles you have to make your own like add some 5 w to a 10w.  see how it feels if its no help then you can drain it out and have another go.

Then again maybe just wait for someone else to come in and give you a better response :OP

[Tom]

g'day freakshow i didn't know the forks could be setup to preload and compression stroke (my first time replacing seals  ) i just wanted the forks to be stiff all round cause i've stiffened the back up alot like the way i feel comftable with it and its gunna be very awkward with a soft front and solid back haha so yes any idea? thanks Tom

[Freakshow]

I have no idea what your riding as fork technology changes each year.  ( i rode a 08 yesterday that is so smooth id list it close to cheating, you can ride no hands in the deepest ruts.

but as a general rule you preload your forks too not sag out when you sit on it, thats the push it has on the ground so to speak. 

Then use the weight and volume of oil/air  to change the way it feels as far as speeds to compress,  the rate pushing up into the forks and back out again (rebound)  the ideal is to run soft enough that you soak up all the hits and fast out enough to get back to where it was, you want it to run as "flat " as you can.  Dont confuse stiff with ridability, you want to use all the travel you have not so stiff you only use the first 3 inches.

Put a zip tie on the fork legs tight enough to hold, run the bike around your normal track, see how far down the legs it ends up, if its not nearly on the bottom you have the right travel, you then just need to weight up your oil and comp to get the feel in travel speed you want.  I like mine loose so it soaks up all the bumps and works in soft tracks.  I think YSS has a Suspention set up manual online, do a seach for YSS and read up,  its a black art but the theories are very simple.   YOu can alway back off your rear.

IF your too Stiff all round you may find your sliding off berms, pushing wide, loosing the front end, getting tired arms, face planting the list goes on etc.   

YOu need to tell us why you want it stiff,     or better still what is the bike doing now exactly,  what dont you like about what its doing and what would you like to do better.

http://yss-australia.com/suspension_problems.php

[Tom]

the forks are the stock forks for a 1981 cr125rb i want the forks more stiff cause its the feel i like and it helps me ride alot better for some reason not sure why but it dos if i was to give the forks there normail oil quantity and give it maybe 8-10psi with it bein maximum 15psi would that stiffen it to a good level cause i still want it to compress full length when needed but i don't want to be constantly bottoming it out ethier. Thanks Tom

[Freakshow]

i dont no much about air forks but assume that crates more comp.  Id be more interested in the springs and the preload to get stiffer off the bat,  BUT giving it a try with a thicker wieght of oil might get you the stiff or slower feel i think your talking about. 

 Did you read the web site above ?

Do the measuring and then ask Walter on here and he will point you in the right direction.  The rest of us just make shit up.  Do the numbers , then post back in here tom.  that way you got all the info, and one of these guys will give you the heads up from that hard data.

[Tom]

thanks for the site freaky helped me understand alot better i'll do some tests get the results and relate back to here. Again thanks for helping out Tom

[Freakshow]

thats what we do :O)

keep you kids off the street.  now be good to ya mum................ :O)

[evo550]

Tom,
The only way to correctly stiffen your front end is to fit heavier springs, the next, less desirable option is to preload the springs you already have, this can be done by fitting a spacer between the springs and your fork caps.
Thicker oil, as freaky pointed out will only increase the compression and rebound damping(Slow the stroke down)
Springs carry the weight, oil and valving control the action(stroke)
Increasing the air pressure, may stiffen the front end but will also increase the rebound ( you might get smacked in the mouth with your cross bar on your first big landing.
I prefer to set up my forks with no air, and just use the valves to bleed any air build up.
Air pressure constantly changes in your forks, usually continues to build, so any set up with air will change by the end of the day.....best to run nothing and bleed your forks every time you hop on, that way it remains constant.
In the words of the great "Mr Know it all" .............you should have known.

[oz555ktm]

 Young Tom Check your Forks may have addjust in the fork legs.
On the end of the bottom of the leg Remove the Black rubber Cap .
Clean out and you shold see the adjuster .

[D project]

I think that comp adjustment came in around 83 on most jap MXers. Wish my 81 rm125 had it!

[Tom]

Thanks fellas for all the info   i've heard from what i believe a reliable source   that if i use air in mi forks it will blow a seal real easily so i think i may go with evo550's idea sounds more relistic dennis i'll deffinately have a look hopeful your right but we can only hope many thanks Tom

[marshallmech]

Tom on my 125RB I run belray 15 oil just changed from 10 and she,s handlin great but I,m a light 74 kilos

Andy viper#70

[Tom]

how expensive is the belray oil? i might try that as im also around the 74-75kg mark also