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Need help with fork rebound

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2013 kx450f with PSF forks, have RT gold valve kits. ok I started tuning the rebound first like most discussions said, at RT base settings the fromt slides out a lot in dry hard pack turns so I start to go in (stiffer) on rebound and it got much better but I am all the way in on rebound and I have not gotten to the point of the bike wanting to knife in. most tuning says get to that point then back off. ok so if I went stiffer in the rebound stack to get it in the more useable range how many blocks stiffer should I go on the RT chart? and I am assuming this would be low speed rebound? thanks all any more info you need please let me know. and the track(s) here are mostly dry, hard pack clay mix wish some softer bermed corners. I have Bridgestone X30 tires on

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I would not use fork rebound exclusively to tune the bike for better cornering.

You may get different problems from the strong reb...

 

you can use more preload at the rear too and move the forks up in the triple clamps.

 

In the end, the kawi will never turn as a suzi...

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I have the forks up to second line in triple clamps, compression feels good, and just put in 21.5mm triples. now I have had problems with rear hooking up too would raising the rear sag to say 103 from 106 cause any differences?

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plus it does seem to be gettimg better as I go in on rebound but just not hit the point of wanting to knife in yet.

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RT fork rebound settings are (although way better than stock in most cases) a little soft for my liking too. I usually end up one or two steps stiffer. Sounds like you could go two.

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ok just so I follow, rebound always confuses me. so on the clickers if I go in/clockwise then that is slower/softer/more dampening? all the different terms confuse me in the rebound. so stiffer on the stack would mean less fluid flow cause stack doesn't deflect so that would make a faster/harder/less dampening? ok and I am using rebound because almost every single tuning procedure tells you to work fork rebound first and go clockwise in clickers until bike wants to turn in too much then back off one or two clicks. that's why I am using rebound now then will go to comp although comp feels good now, a little stiff at top of stroke but all in all its ok. correct any mistakes above please

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clockwise or in=  more damping   results in slower action of the forks (return from a compression slower)  a stiffer setting. 

 

counter clockwise or out =  less damping  results in faster action of forks  ( return from a compression quicker)  a softer setting.

 

clickers are the bleed circuit (the bleed circuit is for lowspeed movements and trail trash / small bumps)  (it is also responsible for your turning characteristics/ line holding).

 

 clickers do not do not effect the shim stack (however they effect how soon a shim stack starts to open ).  the shim stack is tuned separately.  a stiffer stack is less fluid flow thru the piston which results in more damping / firmer ride / slower return of fork after a compression.

 

suspension hydraulic circuits add damping ////not dampening/////dampening is to make something wet/////example I like to add dampening to my wife..ha

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Ok so in this case would you recommend I maybe drill out the rebound bleed hole bigger and not mess with the stack?  I have it at 2.0mm right now.  If you need the stacks let me know and i'll post them.

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you are fully in (clockwise ) with your rebound clicker.  why would you want to make it larger seeing as  you have completely closed it off?

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well if I need to go in more that means I need more/stiffer/ slower dampening right? so wouldn't enlarging bleed hole allow more fluid to flow and thus increase damping the direction I want? or am I thinking it from the opposite way?

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well if I need to go in more that means I need more/stiffer/ slower dampening right? so wouldn't enlarging bleed hole allow more fluid to flow and thus increase damping the direction I want? or am I thinking it from the opposite way?

read what I wrote above again.  enlarging= more flow= softer=less damping.

 

opening the bleed hole(making it larger) gives you less damping.  you claim to want more low speed damping.  does that fork come with a bleed stack on the clicker circuit?

Edited by cj_wai

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Yes it has a bleed stack and when I did the revalve I was missing some shims.  From what RT calls for I was missing (so left out) 20x.10 (1) and 12x.25(1).  So maybe if i bought those and put in the bleed stack it would bring me where i need to be or you think I should go a little stiffer?

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Yes it has a bleed stack and when I did the revalve I was missing some shims.  From what RT calls for I was missing (so left out) 20x.10 (1) and 12x.25(1).  So maybe if i bought those and put in the bleed stack it would bring me where i need to be or you think I should go a little stiffer?

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Ok got ahold of RT, hard for me since i'm 15hrs ahead.  But he said bleed stack won't fix this problem. We did some digging and the DSV from RT calls for a 2.0mm #47 bleed hole in the piston.  Tech support did some digging and he said it should be a 1.3mm bleed hole.  So this aligns with what you guys are telling me.  Ok now what do I JB weld the hold and drill another one or is there another (better way) to seal that hole up?  Thanks.

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Ok got ahold of RT, hard for me since i'm 15hrs ahead.  But he said bleed stack won't fix this problem. We did some digging and the DSV from RT calls for a 2.0mm #47 bleed hole in the piston.  Tech support did some digging and he said it should be a 1.3mm bleed hole.  So this aligns with what you guys are telling me.  Ok now what do I JB weld the hold and drill another one or is there another (better way) to seal that hole up?  Thanks.

there is your problem.  I have heard of people jb welding holes shut.  you could try it.  drill a new properly size hole and return the bleed stack to stock.

Edited by nosila

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The "Digital Valving Search" told you to drill a 2.0mm bleed and tech support says that it should be 1.3mm. Yeah, that will do it. Hmmm... gonna look at a couple of my old build sheets now....

JB weld should work. It's sad that you have to do that to new valves though.

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Wet set my bleed hole on rebound to 1.2mm, didn't have a 1.3mm drill.  But really no difference i'm still going full in on the rebound to get it to turn good.  At the RT clicker setting the bike was horrible it felt like the wheel was lose, couldn't even turn.  Ok now where do I go from here to get the rebound back in the clicker range?  Also the accel and breaking bumps are killing me, how can I soak them up without softening comp and losing bottoming?  As of now it looks like i'm using the full stroke of the forks but not bottoming.  I fooled around with psi and clickers and even went full soft on clickers and breaking accel bumps are beating me to death.  Any suggestions?  High speed comp maybe?

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Here are all my stacks:

cL .15x28 (5)

cLX .10x20

cH .10x28

.10x26(2)

.15x24

.15x22

.15x20

.10x18

Restrictor .15x24(6)

.10x16

rH ..10x26

.10x24

.10x22

.10x20

.10x18

.10x16

.10x14

rLX .10x15

rL .10x28(4)

bleed 1.2mm

float 0.80mm

LSV .10x20(4)

.10x16

.25x12

MVP .10x20(2)

.15x20(3)

MV .10x28(4)

.10x26

.10x24

.10x22

.10x20

.10x18

.10x16

.15x14

.40x25

Edited by pavetim

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