Jump to content

SSS cartridge Swap

Recommended Posts

I've got some KYB 48mm forks from an 03 kx250 and I'm having troubles with the front end and I'm thinking about swapping to SSS forks.  I'm wondering if I can just swap the cartridges of an SSS fork into my open chamber set?

Share this post


Link to post
Share on other sites

What's got you down about your open cart forks?

The whole SSS fork will swap over.  Upper tube diameters are the same at 56/59mm.  You would probably need a yamaha wheel and brake to match the forks unless somehow the KX stuff fits.

Share this post


Link to post
Share on other sites

My stocks forks we're messed with, they'll fully rebound off the bike but on the bike they collapse about an inch and a half when you cycle them. I can pull them up to full extension and they'll stay there if I don't move the bike or push down on the forks. I've had them apart, the spring measures fine, the base valve hasn't been messed with based on the peenings still being there. I'm just looking at options right now. I have a line on some 04 250f forks for cheap that I think will work in my clamps.

Share this post


Link to post
Share on other sites

The 2004 250f forks will bolt right on.  The 48mm bladder fork is what I run on mine.  Same 56/59mm clamp diameters on the 02-07 KX250.

I'm not sure there is anything wrong with your forks though.  What your describing sounds like normal sag.  If you preloaded them so much they rebounded to full extension with the bike on the ground they would be terrible forks. 

As my bike sits right now, with the wheels on the ground the forks drop about 35mm from the fully extended position on the stand.  With me on the bike they ride about 55mm into the stroke.  Plus or minus a few mm.  You get the idea though.  They will only fully extend when that wheel is off the ground.

The only thing that sucks about the 03 forks is getting into the cartridge.  The bladder forks are easy.  The mid drops right out.  If you want to revalve that is a big plus.

 

  • Like 1

Share this post


Link to post
Share on other sites

Thanks Dan I appreciate the response.  I'm actually reading your post on the 05 rmz forks you put on your kx.  Are the 05 and 04 forks similar enough valving wise where I can use yours as a guide?

 

When I compare my forks to my brother's (same bike). While the bike is holding only it's own weight my forks sit at least an inch lower.  I got the 04 forks for 55$ and they are in great shape so in any case I now have a couple sets to play with.

Share this post


Link to post
Share on other sites

The 04-05 KX250f and 04-06 RMZ250 are identical as far as I know.  May be slight changes in valving.

If you're reading the thread I think you are I just updated it.  Been doing some R&D and they just get better.  In current form with the 1.5mm bleed on the mid, no bleed shim, stock springs and new mid valving they are working very well.  I was keeping up with a local pro for several laps last weekend before I whiskey throttled off the track.  The forks were not holding me back. 

Share this post


Link to post
Share on other sites

I do a mix of mx and woods riding, I'm a c level mx rider and probably solid b level maybe high b low a on my best days in the woods.  The biggest problem I had with 03 forks was there tendency to deflect rocks roots and braking and accelerating bumps.  My brother's seem to perform much better.  I know I can't have an ideal setup for both so I would lean towards mx I think.  I definitely plan on disabling bladder when I get them apart.  I've never touched any valving on my forks, I'm very much an amateur in that realm, but I'm confident enough to pull the base valve and probably the mid if it's as easy as it looks.

Edited by DylDog

Share this post


Link to post
Share on other sites

The 03 forks are a lot stiffer on the base valve than the later forks.  I think they actually went too soft on the 04 and later forks.  Somewhere in between the two is best, depending on your preference.  Too soft and the fork will bottom easy and still be harsh unless you take the mid out and make them woods only forks.

Share this post


Link to post
Share on other sites

Hey did you have any problems with your 250 2st axle or wheel spacers working? My wheel does not center and the axle will go in all the way except the last inch

Share this post


Link to post
Share on other sites

Did you try tapping on the axle lightly to drive it in?  They usually install flush with the lug when the alignment is correct.

Share this post


Link to post
Share on other sites

Yes I did it won't budge but goes in fine without the wheel. Seems like the spacer on the disc side is too wide and perhaps cause the forks to get a little duck footed. also the disc doesn't line up centered with the caliper. I know the 03 is kind of a quirky year maybe there's a few things different.

Share this post


Link to post
Share on other sites

found what i think is the problem, the spacer on the caliper side is 6mm longer on the 03 when compared to the 04 250f or your 05 250 2 st, on the other side the f spacer is 1mm shorter then mine.

Edited by DylDog

Share this post


Link to post
Share on other sites

How odd.  I had run 05 KX125 forks on my 03 250 in the past, but now that I think of it I do remember something about modifying wheel spacers.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:


×