Fork Seals- did a search

[Red_Chili]

I did a search but there are still two opinions, I'd like to know before I dive in.

Bike: 1998 KDX 220
Forks are off the bike, caps removed, springs removed, oil fully drained.

Do I, or do I not need to remove the valve body on the bottom to separate the fork tubes? As I look at the exploded diagram, I can't see a reason to (once I remove the seal retaining clip of course). At least one member says the valve body must be removed; another says it does not.

Sumbunny here knows, I'm sure. I'd like to not remove the valve body. I may in the future, to remove the two shims, but I'd like to test out just the XR400 fork springs, 10mm preload, and 100mm SAE5 oil and level by themselves first.

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Oh, and FWIW, I constructed a PVC seal driver. I know the SST for $45 must be nice, but that just ain't in the cards. I used a 2" sprinkler pipe barb fitting that was threaded on the other end, a threaded/glue-on combo adapter, and 3' of 2" Sched.40 PVC. Fits like it was *made* for the job; the end of the 2" barb fitting is EXACTLY right. :laugh:

 

[motorider200]

The base valves have to come out in order to seperate the tubes to get the seals out.

 

[glad2ride]

If you want to separate the tubes, then you DO have to take out the cartridge.

Double check your homemade seal driver to be sure you don't bash the inner edge of the oil seal or dust seal.

Good luck with it.

 

[Red_Chili]

Well, darn it, not what I hoped, but probably what I figgered.
I did look really carefully at where the seal driver lands. It's JUST inside the aluminum outer tube, right where I want it! The ~tight-ish fit should keep it off the lips.

Now on to find that dadgum 14mm allen slug or driver... The local hardware store had none, and though they had metric coupler nuts (which I figured would work in a pinch) they were not JIS- meaning, they were 13mm, or 17mm, not 14mm.

 

[80elkster]

Cartidge Removal

I built a simple tool to fit the cartridge out of a 14mm headed bolt with a 14mm nut threaded on just to the end of the bolt. I then tack welded the nut on. I used a 14mm socket on one end of the tool and the other end went into the cartridge.
P.S. I leave my forks assembled, turn them cartridge side up, compress them about 5" and use an impact gun with short quick bursts to get the cartridge out. Otherwise you'll have to build a tool shown in Canadian Dave's Tech tips to hold the inner tube from spinning.
One other thing before you start, place a socket that just fits on top of the cartridge but not on the fork tube and smack it several times with a hammer. This breaks loose the thread locker (locktite)
You might try reading through the thread I've linked to for a lot of good insight and information
CLICK HERE
Good Luck!!! :cool:

 

[Red_Chili]

Thanks guys. This board is as helpful as my other favorite board for my other life, 4x4wire.com/Toyota Trucks forum. In other words, pretty dadgum intensively helpful!

Thought I would post my experience in case others do a search in future.

I located a 14mm allen | 5/8" allen combo slug at an Ace Hardware near home, A&A Tradin' Post Columbine (in case anyone else near Littleton needs one). They had 3. $1.50, I think MAYbe the gal might have guessed wrong on the price.

The forks came apart without fanfare; compressing them slightly does hold the cartridge enough. I did find a little splooge even though I had drained the forks overnight, so the comments that disassembly really is a good idea just to clean things out are spot-on. While I was at it, I went ahead and removed two shims from the valve body for a remaining total of 8. Note that the narrow washer (not a shim, but a washer) goes on the BOTTOM of the stack. Easy to miss, easy to put on the top, not covered in the FSM. Sticking the 14mm slug in the vise makes a great holder to work on the valve body BTW. Careful not to lose the dadgum spring.

On reassembly, temporarily sticking the springs in and compressing slightly is enough to hold the cartridge for tightening with an impact. Oh, and if you are like me and I know I am, you forgot to buy a new copper washer. No worries, anneal the copper with a torch till it glows, let it cool, works like new. I chose to use my PVC driver to first drive in the bushing/washer. This let me verify that there was no play (woo hoo, saved a buck). I then slathered up the inner tube with Valvoline moly-disulphide wheel bearing grease, slathered up the fork seal, and CAREFULLY slid it into position. I drove it in place. Finally, I drove the dust seal in place. I just figgered it was a better idea to do these separately, no sense pounding on a seal more than you have to. Snap the clip in, I'm golden.

I made an oil level tool out of aluminum tubing, a suction ball, and some fuel line to join them, and marked measurements in 10mm increments. Works dandy.

I made a damper rod puller-upper-thingie out of 1/2" weldable steel tubing (happens to be just about 10mm ID) and an M10x1.0 nut. Temporarily locate the nut with a M10x1.0 bolt and tack weld, you're done making it. Also works dandy.

I used the large black Daystar fork boots to help give my green ride a purple-ectomy.

Job done, much learned, thanks all!

 

[crazybrit]

Does dissassembling forks imply new seals, bushings etc? The manual says to replace all components when reassembling.

I'm just interested in throughly cleaning (8yo fork oil was nasty) before installing new springs and oil -- but not if it means I need to install all new seals.

 

[Colorado]

I'm just interested in throughly cleaning (8yo fork oil was nasty) before installing new springs and oil -- but not if it means I need to install all new seals.

Seals are cheap. Might as well do them if you're taking it apart ... or take them apart to do it down the road.

 

[Colorado]

"Oh, and if you are like me and I know I am, you forgot to buy a new copper washer. No worries, anneal the copper with a torch till it glows, let it cool, works like new."

I believe it's best to quench hot copper in water and quick cool it when you anneal --- if I was correctly informed. Head gaskets aren't available for my old Yamahas, so I anneal and reuse them whenever the head comes off.

 

[crazybrit]

Seals are cheap. Might as well do them if you're taking it apart ... or take them apart to do it down the road.

Well. The seals are like $20 right? As I said, the manual calls for replacement of a lot more than just seals.

The issue is that I DON'T have to take the fork tubes apart.

I was only going to do so as I'd read it was a good way to fully clean out the goop .... but if there is a good chance the seals will be toast after dissassembly I'll probably just flush a 1/2 of ATF into each fork and then refil rather than go thru the hassle of getting new seals and making/buying a driver.

Tony

 

[glad2ride]

Fork oil seals SHOULD be replaced after tube disassembly. I would suggest you skip it if you are not wanting to get too involved.

 

[crazybrit]

Fork oil seals SHOULD be replaced after tube disassembly. I would suggest you skip it if you are not wanting to get too involved.

Well let me ask the question in the backwards form. Just trying to get a better understanding .....

How likely is it that I'll have a significant goop buildup and how useful is it to clean it out? Noticeable change in fork performance?

The bike is a 1998 and the old oil was really very grey when I drained it. I doubt the oil or seals has ever been replaced.

The manual says (when reassembling) to replace the dust seal, retaining ring, oil seal, inner/outer guide bushing and cylinder valve assembly gasket .... I noticed the Pivot Works fork kit is like $75 which I'm assuming includes all of these items .... of course I've heard mixed things about a/m fork seals.

The fork seals were not leaking though I did notice when I had them upside down to drain that I got a little flow past one of the seals and onto the inner tube. Doesn't seem to leak when the fork is normally oriented but I've not refilled them yet either. Easy to temporarily fill with cheap ATF, reassemble and verify it's ok though.

Tony

 

[steve.emma]

recently did an overhaul on the front forks of my 99' 220.
replaced the fork springs with 02' xr400 items, did the shim removal mod set oil level to 100mm with 10mm preload etc..
works really well now and handles the jumps a treat. getting a bit more arm pump on the mx track now but its worth the better handling.
when the forks were apart i removed the cartridge and cleaned everything but my seals werent leaking so i didnt seperate the tubes or anything and have not had any problems with leakage since. it would have been better to have done the seals also but then you really need to replace the bushings that support the tubes and by now the overhaul cost is starting to get up...
either way though i can really recomend the springs and shim mod,well worth it.

 

[glad2ride]

Hi. There are way too many variables to give you an easy answer. SOME improvement is better than none.

You may want to find the cheapest ATF you can buy, pour oil in, put the caps back on, set them upside down, wipe the inner (chrome shiny) tubes and then see how much drips down. Oil won't leak upward, so any damaged oil seals on conventional (right side up) forks won't show up too well in normal position.

On the flip side of your aftermarket fork oil seal comment, I doubt there have been many OEM fork oil seal complaints. :-)