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2013 SFF Fork Rebuild - Trashed Center Bolt/RebAdj

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I got a set of new bushings and a green SKF seal kit and some oil to hopefully reduce the friction in my '13 SFF fork.  I am not a pro for sure, but I have done a couple of WP twin cart forks, and a 2010 Honda CRF250R Showa 48mm fork (which btw is the fork that the new 48mm SFF is based on).  I have never had so much trouble getting the center bolt out.  The SFF fork damper side on the left should be a piece of cake to take apart with no spring, and mostly it is, but I beat on the center bolt with a socket and hammer to break the threads loose and then went at it with a 21mm socket after putting the fork dropout in a vise.  It took a ton of force to get it going, and it never got easy to turn.  It did not seem to have a lot of loctite on the threads, but it must have been strong, or else the two different alloys bonded together enough to cause this.  I messed up the threads pretty good.  I ordered a new center bolt/reb adj and it is cheap luckily ($26).  If it were a Suzuki RMZ, which has a very similar fork, this part would be $130!  Maybe they have a better bolt/adj and it would be smart to use it.... who knows.

 

Anyway, I do not know if I should have used a heat gun prior to trying to remove the bolt, but this has not been an issue in the past.  I am confident I can clean up the threads on the dropout and get the fork going safely again, but this is an issue in my mind, that kawasaki should work on. People are going to do their own fork rebuilds...they should not have to damage the fork to remove this bolt.  

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Did you hold the damper assembly with the "special tool"? Only reason I ask is because I tried to remove that bolt, too. Bottom of fork. It spun, but didn't back out. I ended up leaving it alone after a couple of turns. If you know what I am talking about and it isn't the same thing as your issue, let me know. I am sure to need that thing out at some point and would be glad to learn from your experience.

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Did you hold the damper assembly with the "special tool"? Only reason I ask is because I tried to remove that bolt, too. Bottom of fork. It spun, but didn't back out. I ended up leaving it alone after a couple of turns. If you know what I am talking about and it isn't the same thing as your issue, let me know. I am sure to need that thing out at some point and would be glad to learn from your experience.

I couldnt get that out on my SFF fork either, it just spins in there so I left it. Just sprayed carb clean down in the lower tube and then used a rod to clean it out with some paper towels on it.

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This is the center bolt/reb adj I am talking about.  It came from the cartridge side (left).  I did turn the reb adjuster when needed on removing the bolt, since these forks have a d-shaped rod and will sometimes run out of travel on removing the bolt.

 

I need to remove the one on the spring (right) side now and it is really hard to break loose.  I am going to heat it up a lot before I try to remove it.  Same bolt without the adjuster on it. 

 

It is a M22x1.0 thread size, and I ordered a tap to clean up the droput, so hope it will work ok.  BTW the stock fork seals suck!  So much friction!

 

file_zps8d85885d.jpg

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and here is what the base valve shim stack looks like, stock on a 13KX250F.

 

file_zps47b37af7.jpg

Edited by drzadam

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 I did the spring side and it went much better.  Chock most of it up to me being a newb with showa forks.  I heated the center bolt for about 3 mins on the hi setting of my cheapo b&d plastic heat gun.  Then I used my air torque gun.  It got it out and after it started a few turns, it came out smooth and easy the rest of the way.

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also, I did have to use a shaft holding tool that I recently bought.  it is a racetech with 4 sizes 10 12 12.5 14.  I used the 12.5 to grab the damping cartridge shaft at the end and then I was able to get the center bolt off the cart shaft.  I think that this is a new problem because in the past, with the spring pressure on the shaft it made it so the locknut never turned before the center bolt.  The SFF cart side does not have any pressure on the shaft when you take it apart, which is nice in every way except for this.  As for the racetech tool, it worked great.  It did not marr the shaft or make any marks on it at all.  I expected it would make some, but nothing.  That is good tool. 

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and here is what the base valve shim stack looks like, stock on a 13KX250F.

Anyone know what the settings are for the 14 KX250F?  I want to make the damping a little softer in the low mid and hi, so I will probably start with the hi and go from there, but I also have considered using a 2-stage stack with a crossover shim after 3 or 4 of the 31x.15 shims.  I know the euro version of the 13 KX250F has less transition and fewer shims in the ramp down part of the stack.  Any ideas???

And importantly last, do I need to file off the threads above the nut on top to remove it?  It looks like it is not peened, unless the whole top is peened very uniformly and not in 3 spots like I've seen.

 

 

file_zps47b37af7.jpg

Edited by drzadam

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and here is what the base valve shim stack looks like, stock on a 13KX250F.

 

file_zps47b37af7.jpg

 

Where did you find this picture with the shim stack explained like this? I have an 06 kx250 that was set up for woods from the original owner and I want to set the shims back to stock as a starting point. If I could find a picture like this for my bike that would help out so much.

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thank you very much ;)

sorry, but you are sure that be original oem kx250f 13 ? i know BV start (11) x 31 .15 and finisch with 19 ...........  :rolleyes:

you have to ask GDI70 if he is sure, but I guess it is correct. often there's a difference in EURO/US stacks, so

10 instead of 11 face shims is very close, and he noticed a 19 clamp

 

buona giornata

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ok, I disassemble mine to be safe, so the photo above, is not original base valve? 

this sff 2° step don't like, the front fork being too stiff, i just try a revalving, remove  1 shim 31 in BV and 2 shim 25 in midvalve and open all preload ;)

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hello, do you have setting shim original OEM(low-mid and return) of the sff 2 kx250f 13? thank you very much 

x2

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