1981 XJ650 fork seals

I recently bought an 81 XJ650. The bike is mint except for one of the fork seals leaks a little bit. I ordered some factory seals from the dealer. Has anyone who has done this before have any tips or important things I should know about changing out the seals? Any special tools required? I have a Haynes manual for the bike that gives a vague description of how to change out the seals. Any help is appreciated.

Thanks

 

Welcome to the forum Mitchhill, your in the right place. I've rebuilt several of the 81s forks and they can be a bit intimidating at first. Tools you will need: an impact gun (OPTIONAL, you can do this by hand but this is way easier, electric or pneumatic), a bunch of 3/8" extensions, an 8mm (that or 6mm, can't recall which your bike needs, but you should have both regardless) allen wrench, couple of small screwdrivers (to pry out the seals and retaining rings), and a bolt with a 17mm head (or is it 19? can't recall, you will see this setup in your Haynes, it works and is cheap).
That ought to do it. Also use 15 weight oil at least, not the 10 weight specified. The front end on these bikes tend to be really soggy.
1. Read the fork section of your book, become familiar with the parts, their location and function. I would follow their instructions in the order they specify.
2. Drain the oil out.
3. (one assumes you have already pulled the front tire and axle at this point) Note: MAKE SURE THE BIKE IS SECURELY BRACED AND CANNOT FALL OVER!! You must pry out the rubber cap at the top of the fork tubes to access the seal caps.
3. Push down on this seal cap with some form of rod or drift (preferably brass or something non marring that won't puncture a hole in your hand). This may take some effort which is why your warned to brace the bike. There will be a thin circlip that must be fished out of it's groove above the seal cap in order to pull the cap. This may be a bit of a challenge by yourself so source a buddy before hand. The circlip may also be rusted into place so be sure to have some breakfree handy to soak it. When the clip is removed you should continue to maintain pressure on the cap since it is under pressure from the spring. SLOWLY ease the cap out and capture the parts.
4. Pull out the spring noting the orientation of the spring.
5. Hit the allen bolt on the bottom of the stanchion with the impact and it should release. If not you will need to whip up the stack of nuts mentioned in the book and drop it down the tube to lodge in the bolt. Here is where you will need all those extensions. Use an appropriate number of extensions to get a socket down on the nut/bolt tool to hold it in place and, while holding this, spin out the bolt on the bottom of the fork leg. You will have some dripping so be sure to have a catch basin of some sort in place. Invert the fork and let the piston assembly drop out into a rag or your outstretched hand.
6. Pry the dust seal at the junction of the slider tube and the lower fork body. It will take a little time and patience but it is doable with a very thin bladed screwdriver and a little finesse.
7. Pry out the seal retainer clip. In practice I've found most of them to be rusted out so be prepaired to replace them. I used an appropriately sized internal snap ring as the dealer wants darn near $13 a piece for those stupid clip (as compared with less than a dollar a whack for the snap rings).
8. Pull the fork tube up, using it like a slide hammer, to dislodge the old seal.
9. Clean out the tubing and lower assemblies.
10. Lubricate the new seal and slip it into place. Replace the clip. (easier if you install the seal first and insert the tube through the seal, but be forwarned, the lip may roll under on you so watch out!)
11. Reinstall the dust boot.
12. Insert the piston assembly back down the tube in the correct direction. Insert your tool to hold it and tighten the lower bolt to spec with a little daub of locktite.
13. Pour the specified amount of fork oil back into the tube.
14. Insert the spring in the correct orientation (as noted earlier).
15. Muscle the sealing cap back on top of the spring and thread it back into the tube (this is the hardest part, help is invaluable here).
16. Reinstall the rubber cap. Your done!

Good luck to you on this task, it isn't the easiest but it sure isn't the hardest either.

 

Thanks for the info. I shall try it this weekend.

 

What quantity and what oil do you think we should use?

 

Assuming you have the 81 H model such as mine, you would need 262 cc per fork of 10W/30 motor oil or 10 weight fork oil. If you have the J model, you would need 278 cc's and the RJ and UK versions would use 236 cc's. This is quoted out of the Haynes. I have posted all 650's since we have an international audience and your particular model wasn't mentioned in your post. I personally run 15 weight fork oil in mine since the stock setup is a little soft for my tastes. I've run as heavy as 20 without any problems. Maxima, Castrol, BelRay, PJ1, Torquo, and many others make good oil so you have a wide selection to choose from given your location. I don't have a favorite fork oil brand yet, everone gives me their left over bottles when they transfer and I haven't had to buy any in over 15 years! I just use what I have stored. I'm currently running a mix of Maxima 10 weight with Torquo 20 weight and I'm hoping it is something close to 15 weight by volume. The PJ1 is neat stuff as they add a molybdenum (MolyB to you grease freaks) formulation to their oil. It looks used straight out of the container but is good to go. Hope this helps and that you have gotten your seals done. Magolo, did you get the pictures I sent you?

 

Im changing my fork fluid and I cant get one of the spring seats to pop out the top,i have an 80 xj 650 btw, the other one came out easily..is there a trick for unsticking it?

 

It took me 9 months of trying before another forum member suggested Kroil: http://www.kanolabs.com/google/

It worked when nothing else did. One tip: DO NOT hammer the plug down in the tube any further than just to clear the ring clip; the inner tube is tapered and you can jam the plug.

Also, loosen the upper fork tube clamp bolt, it can sometimes contribute to a bind on the plug.

Two additional tips for rebuilding forks: It's much easier if you remove the forks from the bike altogether and work on them individually; and you can use a spark plug socket that has a 19mm hex cast into its base, flipped over, on a bunch of long extensions to hold the inner damper tube.

 

Hi Robert -
I know this is an O L D thread, but I'm working on this same project and had a question for you about your post if you're still around (or anybody can answer). I got the the retaining rings out today, and was expecting the seal caps to be easy to remove since they are springloaded. However when I slowly released pressure off of them (so I could get the circlips out), they didn't come out! They went back to their original position, but not far enough out of the tube so I could grab them with my hand. I was expecting the springs to push them beyond the top of the tube so I could grab them with my hands. Instead, they are BELOW the rim, so I can't even grab them. They did rebound a little bit so they're not stuck or wedged in. They might or might not be free in there. I wish I had a strong magnet to see if they would suck out that way. But I can't understand why these caps, which are springloaded, didn't just pop out. Any ideas?

1) The circlips are definitely out
2) The bike is on the center stand, but still resting on the front wheel. Not much pressure is on the wheel as I can lift it no problem. Any reason why it would need to be off the wheel to get the seal caps to protrude more?

Confused....

 

The pinch bolt on the upper tree clamp is most likely applying pressure against the fork tube keeping the cap from comming out. Try loosening the pinch bolt.

If the cap still refuses to come out. Try cycling the fork.

Warning!! Do not stand over top of the fork while releasing the pinch bolt. The cap could shoot out with some force. It would be a good idea to place a heavy rag over the top of the fork to provide a means of retaining the cap in case it should go flying.

Ghost

 

I think I tried this already. is the pinch bolt just the clamp type assembly at the top of the fork stanchion? 12 mm wrench? I loosened it, still no go. It's weird because the cap bolts still move when I push down on them and they spring back but they stop, like they're bottoming out on something. But the circlips are definitely out. I only tried the pinch bolt on the left side of the bike, but it was all the way loose. If we're talking about the same bolt, but I can't reckon what else you'd be referring to.

 

That is the correct bolt.

Have you tried spreading the clamp with a screwdriver, or similar??

Ghost

 

I just tried to spread the clamp. It's a piece of plastic and I gently pried it open, but nothing. Didn't want to pry too hard in fear of breaking the plastic. I'm attaching a picture of what it looks like I'm trying to take off. I can't understand why this cap isn't just springing out. The circlips are removed what the heck is going on? It's the same on both sides.

It doesn't seem rusted tight either because I can push it down with good action and it springs up nicely but just stops like its hitting something. Any ideas? What is the damper hex bolt on the bottom of the spring? Do I need to mess with that?

 

It's not plastic, it's aluminum. Still don't want to pry too hard on it.

Probably a ridge of corrosion from the circlip catching the cap. First thing I'd do is support the bike - when the caps come off the nose will drop with possibly results you don't want.

Put some penetrating oil on them (Bigfitz swears by kroil). Then take a punch and a hammer and repeatedly tap them down a bit and let the spring kick them back up. They should eventually worry themselves out. Don't bang down on them - they can get stuck if they go much below their normal position.

If that doesn't work you can try removing the fork and compressing it with a bar clamp. The extra spring pressure might do the trick.

I know one more trick, but it is a next to last resort.

 

OK, thanks for the reply. I'll try it. Kroil is good stuff. stay tuned....

 

Got em! Thanks for all the help

 

im trying to get my top cap out on my 82650j and am having a similar problem. My cap bolt isnt moving at all though. I got it down just enough with a bar clamp, and pulled the circlip out, and it wont move up or down at all. the top of the cap is just above the bottom of the ridge for the circlip, and comparing it to the other one, it doesnt seem like its the whole way down.

ive pulled out the air valve, turned the fork over, and cycled it repeatedly until it bottoms out. and ive tried tapping it in a little bit. it just doesnt want to move...

 

ive also tried wrapping the leg in question in a ratchet strap and cranking it down and using the pressure so i can break the retainer bolt loose, to no avail...

 

Top caps that won't come out are usually hung on a nice neat ring of rust.

I fought this fight; X 2 bikes.

NO PRODUCT OUT THERE would work. You name it. Liquid Wrench, PB Blaster, JB80, CRC, nothing.

Then a forum member suggested Kroil: http://www.kanolabs.com/google/

Through Harbor Freight, free shipping: https://secure.cnchost.com/kanolabs.com ... r_hf.shtml

 

it really makes that much of a difference? ive always treated those sprays as one in the same. its been soaking in both pb and liquid wrench. ill see if pep boys has kroil though. i like to avoid harbor freight.

 

+1 on Kroil for working on those fork tubes. It's the only thing that gets into the rust and breaks it down enough to get those apart.

MN

 

Kroil is not sold "retail" they only sell direct.

The Harbor Freight deal is only through Harbor Freight; or you could get it directly from Kano Labs (and pay the shipping.)

And yes, it makes that much of a difference. I thought the same thing you did; and only tried Kroil because I was getting desperate when nothing else was working, for like 5 months or better.

Kroil was the only one that worked.

 

crazy, ill give it a shot. thanks

 

Sounds like yours is worse than man was. But I soaked it in WD40 and smacked it a bunch of times with a hammer. Funny thing was I was smacking the left side, and the right side flew out. Good thing nobody was there for the top cap to hit. A little more smacking (with a socket acting as a punch) the left side came out. I take it you've smacked it enough times?

What about heat? When I used to work on boats, we used Kroil all the time and we also applied a little blow torch heat to really stubborn stuck fasteners

 

I personally would not heat the upper end of my fork tubes. Think it would be best to use the Kroil and let that do the work. Also be extremely careful beating on anything with a spring under it. Be sure to have safety glasses on when you work on something like this.

 

I've smacked it the point of actually getting all the rust off the top of the bolt. Gonna order some kroil now

 

Took the leg in question up to the shop this morning. Hit it with some heat(air valve removed) and it popped right out

 

i just did my seals last night
that top part in the picture was easy for me. first motorcycle but I'm a car mechanic and before that a bicycle mechanic so experience helped me.

TIGHTEN THE CLAMP. Yank her down to full torque spec and go even farther if u have to. use a big flat punch and ram that top piece with a dead blow hammer.
it should go in. And the pressure from the clamp will hold the piece in there for 5 - 10 seconds depending on your torque.

quickly release the cir clip. U got plenty of room and no need to have a friend help u! and i find 5 seconds plenty of time as well. if not, try again. won't hurt.

Then you release the clamp bolt slowly and it'll spring out.


BUT BEFORE YOU RELEASE THE TOP, undo the bottem bolt.
The spring pressurizing the system helps keep the internals in place.
Impact gun it if you have one. And the bolt should come off nicely. Oil will come out, be warned.

Otherwise, if you do it as the hayes manual said, and undo the top first........ you run into hell trying to build a tool which they suggested in order to keep the internals from spinning as you loosen the bottem bolt
\

 

This should help.

http://xj650.blogspot.ca/2009/01/how-to-clean-enrichment-circuit-well_04.html

 

Just a quick word of caution here in regard to hammering on the internal cap plugs:

The inside bore of the fork tube is TAPERED just below where the cap fits, they're NOT just a simple "tube." If you hammer the cap in too far beyond what's necessary to pop the circlip out, you can end up wedging the cap in the top of the tube.

It's also not necessary to build a special tool for getting the forks apart. You need a spark plug socket with a 19mm hex cast on its base; flip it over and add every extension in your toolbox and you have a damper rod holding tool. (This doesn't apply to the later bikes that use a 22mm hex.)

 

YES! Sorry i didn't point that out. If your hammer have become good friends with your hands over the past few years, you should notice the ledge easily. Don't try to force the cap any farther down. gives u plenty of room to play with.

Thanks for pointing that out.

And THANKYOU for the tip on the 19mm. I couldn't figure it out for the love of god and the hayes manual doesn't say nor do I have anything really that I could use to try without risking loosing it in the fork and leaving me royally f**ked. Which lead me to some boiling braincells and realizing I can just slam the cap back on the compress the springs in there to help hold the rod in place

good to know it's a 19mm for the future.

 

I'm bringing back an old thread if that's alright. I'm sitting with this issue at the moment. The cap on my fork is stuck. When I took it apart today, the cap was actually a millimetre or two below the lock ring, so I had no trouble getting the lock ring out. The cap hasn't budged with all my efforts of getting it out. I'm worried it's too deep and is now wedged stuck as some people warned could happen. It's also pretty rusty. It's soaking overnight in some rust remover to see if that helps. Anyone have any other suggestions? How do I get it out if it's wedged too deep?

 

Hydraulic pressure does wonders.

Warning: This will be messy.

Thoroughly soak the plug with a good penetrating oil (NOT WD-40). Repeat this for a few days.

Remove any corrosion from the inside of the upper fork tube with 400 grit wet-and-dry

Lay down a sheet of 4mil plastic to protect the ground, or the floor of your garage.

Get a scissor jack.

Park your car just far enough from the wall of your garage (or some other secure object) that you can set the fork leg and the scissor jack between them, with the base of the jack resting against the tire, and the top against the fork leg.

Extend the jack, therby compressing the fork leg.

The plug will pop out, along with the oil seals.

If the oil seals pop out on their own then you will need to drill and tap a hole in the plug so it can be extracted using a slide hammer.

 

No such luck, It compresses all the way and still no 'pop'. It's sat two nights over now with penetrating oil and it doesn't seem to budge. I managed to get one of them out, but the other is really in there. Pictures attached are of the one that I got out, as you can see is quite pitted, the other is the one that is still stuck in there.

 

And here is the still stuck one.

 

In theory I could just leave it in there and not worry about changing the 'o-ring' right? The point of the cap is to not let fork oil out the top, and if I can't get it out, then oil won't get out either. Right? I'm still able to change the seals and all the other parts, just not the 'o-ring' on the cap.

Other side to that is, I've poured a fair amount of penetrating oil in there by now, I'm not too sure how I'd flush that out and get it nice and clean inside, without getting the damn cap off. I've used all the man power and various methods I'm capable of.

 

You won't be able to inspect the internal bushings, or flush all of the old oil and grit out, and it will be much more difficult to get the oil seals out with the spring in place.

Do you have a helper that can depress the cap while you use a strip of 400 grit wet-and-dry to clean the corrrosion from the lip of the fork tube?

If the cap is still not coming out after that you can use an immobile object, and your car, to put a little more force to it without damaging anything.

1. Lay down a sheet of plastic to catch the oily mess that should occur during the process.

2. get a scissor jack, or a bottle jack that is valved to wotk whild laying on its side.

3. Park yor car close enought to the immovable object (garage wall, or a tree, or similar) that you can lay the fork leg down against the with room for the jack between it and the car tire.

4. Extend the jack.

5. As the fork compresses the increased hydraulic pressure should pop the fork cap out (this happens most of the time). If the fork seals pop out before the cap does, then you will have to drill and tap the fork cap so that it can be removed using a slide hammer.

 

I already have the oil seal out. I think the cap is already pressed as far in as it goes, which is why it is so stuck. When I took the fork off the other day, I didn't need to depress the caps to get the 'C-clips' out at all. The cap is a millimetre or two bellow where the 'c-clip' is supposed to sit, so I think it is wedged down into the slightly tapered bit of the fork tube.

 

I appreciate the tips though, I don't want to give up on it! I'll leave it again over night with more penetrating oil, and try more pressure tomorrow!

 

Am I seeing the pic wrong? It looks like the cap already has a threaded hole in the middle that would allow the use of a slide hammer or a home made puller of sorts. Also, what about the heat suggested in this post earlier, has that been tried? Using something like a heat gun (not a flame) to expand the fork tube should help.

 

Yea, Yesterday I attached a tie down straps to the cap, and another strap to the fork tube. I tightened the straps around a tree and the bottom of a tick fence, ended up ruining the fence rather than pull the cap out... Also tried heat, although with a flame as I don't have a heat gun. Is there a difference if I do it with a heat gun?

 

No it would not be different with the heat gun. I suggested a heat gun simply because of the flammable nature of oil. Doing both together would be good though if you haven't tried that - heating the tube while pulling on the cap with a strap. Problem with the strap method is pulling at even a very slight angle not perpendicular to the tube is going to cause problems.

The slide hammer as K-moe suggested is still likely the best bet, as it would shock the cap, and also allow a bit of back and forth motion on the cap in case it is wedged at an angle. Using heat and the slide hammer together would also be a good idea. Also, if the cap is wedged or becomes wedged because it is not perpendicular to the tube could be corrected by a slight tapping motion with a brass punch around the outer circumference of the plug.

Patience is also good here, you mentioned earlier giving it another night of soaking, which is a good idea. Hopefully, you have the Kroil, which is highly recommended by the member on this site.

 

Well, nothing seems to be working. It hasn't moved in or out at all. I'm starting to lean towards just leaving it in and trying to flush it out as best as possible, renew the oil, and away we go. I can still put a new oil seal on etc. Just no new 'o-ring' on the cap bolt. Anyone think that would be a terrible idea?

 

Very terrible. The compressed cap is loading that fork differently than the other. Both forks should be set up equally. Imo since k-moe's tire/jack technique didn't work (which usually does) use his hammer jack suggestion. Replacing the too pitted to be re-used cap is a lot cheaper than having to replace a damaged fork.

Gary H.

 

Considering how pitted the other fork leg is, you'd be better off looking for replacement forks. I don't see an o-ring being able to seal properly without having the bore-worked.

 

That's ^ true too.

Gary H.

 

Yea, I figured as much so I've been looking around locally for replacement forks. I've found a couple forks from an XJ650 Maxim. Does anyone know if there are fitment issues? I essentially only need to replace the inner tube and top cap, everything else of mine is great. Are the length and diameter of the inner tube the same on the XJ650 Maxim and XJ650RJ Seca?

 

One source says they are both 36mm diameter, another says the Maxim has a 26mm air assisted telescopic fork.