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Is this a worthy reason for a fork upgrade?

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So was leaking on my right fork seal which was strange cause I just put new ones in recently,  on closer inspection i have a nice gouge on the coating and it's a finger nail hanger not just a surface scratch.  I've never had this issue , is diy repair on this possible cause if not I'm assuming this is gonna cost more to repair than it would to just get some other used forks for? These forks suck, theyre old oc kayabas from an 04 rmz250 so was thinking of doing a swap anyways, guess now would be the time unless it's something I can repair cause I'm saving for a new bike so would rather not get new forks. Also i would just hate to replace the seal just to find out the sanded and smoothed out scratch was still doing damage and be right back I'm the same boat that I am now?  Any opinions?

It was hard to get good pictures!

20170408_180240.jpg

20170408_180409.jpg

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You can fill that with epoxy if you do it right.  Knock off the high spots, fill the low spots and go back over it with a sharp edge to knock off any excess.

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Awesome thanks I'll give that a try. Instinctively I was thinking along that Iine  but just temporarily and had some super glue laying around so I tried that, hopefully it will last at least for tommorrow. Hmm maybe I'll go get some epoxy now. I have jb weld will that work?

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JB weld hasn't let me down yet.  The key is degreasing.  If you get it truly clean and dry it will stick.

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I will be interested to see how it works.  those 46's are pretty common and avail cheap.   but there is no reason for doing that if 3 dollars will do it.  

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I've fixed a bunch of those over the years as we ride almost all rocks.  No problems.   I use sharpening stones.  Level high spots, clean very well with contact cleaner and a clean brush, fill with JB Weld and scrape excess.  Let cure and again dress level.   Finish with crocus cloth.    New seals AND BUSHINGS as they will be damaged.

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On 4/9/2017 at 10:37 AM, turbo dan said:

48's on this one.  Good forks with a little work.

Turbo dan, when I replace the fork seals should I do any other mods while they are tore apart? When I bought the bike it had RACE TECH stickers on the forks but I didn't see any goldvalves or anything that stood out last time I had them apart but then again I was rushing just to get the new seals in so was just concentrating on that. What should I look out for while inside? I ride pretty fast and and can keep up with B level woods guys through nasty rocky terrain around here but I occasionally do mx and they seemed to bottom out easily on bigger jumps. I know I'm looking for two totally different things suspension wise which isn't ideal but maybe there's a compromise?

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There are a few things you can do that will make the fork work better everywhere.  First thing is to remove the bladders and teflon seal ring from the cartridge.  You will have to lower the oil height from the factory spec to compensate.  I would recommend 100mm for bottoming resistance. 

Next thing to do, if you can, is stiffen the base valving.  Stock uses a stack of six or seven .1mm thick face shims on the base valve.  Either replace these with five .15mm thick shims or, if you don't want to order shims you could get some benefit from pulling the crossover between the face shims and the high speed stack and pulling the top, smallest diameter shim off of the stack.  This helps the cartridge build pressure and makes the fork work better across the board. 

Since the mid valve is so easy to access on these forks, you would do well to pull four face shims off of the rebound stack.  Stock has seven shims and this holds the fork too low in the stroke, especially over successive fast hits.  Another thing you could try is pulling only three shims and drilling a .5mm bleed hole in the mid valve piston.  I haven't tried this yet but I want to.  These forks already have a bleed shim on the compression side of the mid valve but I think they need more to really work well at the top of the stroke. 

The real fix for these forks in terms of bottoming is stiffening the mid valve stack and closing up the float.  This is a real trade off too.  The stock mid valve float is too large and the damping on big hits is too little too late.  Stiffening the base valve is a start but the mid is where the heavy lifting is done.  For the riding I do bottoming control is the first priority.  I closed up the float to .25mm, added a face shim and stiffened the high speed portion of the mid valve compression stack.  It works 100% better than stock and doesn't feel any worse to me on chop or square edges.  I wheelie over that shit anyway whenever possible. 

Just pulling the bladders, stiffening the base and lightening the rebound damping will make a difference.  Start there and decide what you really want in terms of compliance in rocks and roots VS bottoming control on big jumps.  In my opinion, I can deal with a little harshness on small stuff.  I can't deal with metal to metal hard bottoming on jumps.  The stock forks don't really do anything well, so they can get better even before you make compromises.  Start there and see what you think. 

I also use motor oil in these things.  I'm sure people laugh when they read that.  Kawasaki owners manual says KYB 01 -or- SAE 5w20.  So I took the ball and ran with it.  5w20 works.  0w20 works too.  Been running that stuff for years.  Change it every few months, which is super easy in these open cartridge forks, and you will save hundreds over using the expensive KYB oils.  I like the low viscosity, energy conserving motor oil better than ATF since it contains friction modifiers that would ruin an automatic trans.  It is slippery stuff.  I suspect the viscosity of the 0w20 is not far off of ATF anyway.  I save the ATF for the rear shock.  I know, you were already chuckling about the fork oil advice.  The hits just keep coming.

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If it works with no wear , it works

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On 4/10/2017 at 10:24 AM, GP said:

I've fixed a bunch of those over the years as we ride almost all rocks.  No problems.   I use sharpening stones.  Level high spots, clean very well with contact cleaner and a clean brush, fill with JB Weld and scrape excess.  Let cure and again dress level.   Finish with crocus cloth.    New seals AND BUSHINGS as they will be damaged.

Thanks for the tips. I tried superglue and it didn't work great even after 4 coats, they are probably too deep so gonna try JB weld this weekend. I also just found out that my Dad's bike (which is my backup bike since he doesn't ride too much anymore) has the same exact issue on the same exact spot probably because where I ride it's super rocky, I think they are the same forks it's an 04 YZ250F which he picked up recently so I'm not sure on the bike specs but the caps and clickers look identical. So it looks like I have two stanchions to do now!

Why don't they make the fork guards go all the way up? that seems like a simple way to prevent this!

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I just rode Moab and found one of my stanchions has about the same. I'm going to go at it with some sand paper and a stone (or file) and see if that alone will do the trick.

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1 hour ago, turbo dan said:

There are a few things you can do that will make the fork work better everywhere.  First thing is to remove the bladders and teflon seal ring from the cartridge.  You will have to lower the oil height from the factory spec to compensate.  I would recommend 100mm for bottoming resistance. 

Next thing to do, if you can, is stiffen the base valving.  Stock uses a stack of six or seven .1mm thick face shims on the base valve.  Either replace these with five .15mm thick shims or, if you don't want to order shims you could get some benefit from pulling the crossover between the face shims and the high speed stack and pulling the top, smallest diameter shim off of the stack.  This helps the cartridge build pressure and makes the fork work better across the board. 

Since the mid valve is so easy to access on these forks, you would do well to pull four face shims off of the rebound stack.  Stock has seven shims and this holds the fork too low in the stroke, especially over successive fast hits.  Another thing you could try is pulling only three shims and drilling a .5mm bleed hole in the mid valve piston.  I haven't tried this yet but I want to.  These forks already have a bleed shim on the compression side of the mid valve but I think they need more to really work well at the top of the stroke. 

The real fix for these forks in terms of bottoming is stiffening the mid valve stack and closing up the float.  This is a real trade off too.  The stock mid valve float is too large and the damping on big hits is too little too late.  Stiffening the base valve is a start but the mid is where the heavy lifting is done.  For the riding I do bottoming control is the first priority.  I closed up the float to .25mm, added a face shim and stiffened the high speed portion of the mid valve compression stack.  It works 100% better than stock and doesn't feel any worse to me on chop or square edges.  I wheelie over that shit anyway whenever possible. 

Just pulling the bladders, stiffening the base and lightening the rebound damping will make a difference.  Start there and decide what you really want in terms of compliance in rocks and roots VS bottoming control on big jumps.  In my opinion, I can deal with a little harshness on small stuff.  I can't deal with metal to metal hard bottoming on jumps.  The stock forks don't really do anything well, so they can get better even before you make compromises.  Start there and see what you think. 

I also use motor oil in these things.  I'm sure people laugh when they read that.  Kawasaki owners manual says KYB 01 -or- SAE 5w20.  So I took the ball and ran with it.  5w20 works.  0w20 works too.  Been running that stuff for years.  Change it every few months, which is super easy in these open cartridge forks, and you will save hundreds over using the expensive KYB oils.  I like the low viscosity, energy conserving motor oil better than ATF since it contains friction modifiers that would ruin an automatic trans.  It is slippery stuff.  I suspect the viscosity of the 0w20 is not far off of ATF anyway.  I save the ATF for the rear shock.  I know, you were already chuckling about the fork oil advice.  The hits just keep coming.

Turbo Dan that's some real good stuff and exactly what I was looking for. Thanks for taking your time to write that all out, it's super appreciated!!!:thumbsup:

Everything you said pretty much jives with what I am looking to improve on so gonna dig in and try some of these things out but I may have a few questions along the way so hope you wouldn't mind if I ask if I get really stuck.

 

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