Latest experience with fork seals...

[Shuriken]

Well, I haven't had much time to ride this season (and it's fast drawing to a close in Utah, it seems) and my bike has been out of commission for awhile. Sick of that.

So yesterday I decided I'd check/change the middle/final oil and maybe tear into the front forks to change seals. What a dirty job.

Of course the middle and final gearbox fill bolts were stuck solid. The allen wrench alone wouldn't budge the bolts and they were previously stripped a little. I was able to latch onto the middle gear fill bolt with vice grips, and at the same time, used the allen wrench with a cheater bar and was able to unscrew the bolt. The rear was easier.

I don't think the oil had been changed in a long time. Nice to get rid of the black ooze and fill with fresh clean gear oil.

Was also going to color-tune but didn't have time. I did a quick carb synch with the trusty Morgan Carbtune, though. Will work more on carbs and jetting later.

Now on to the fork seals....
Had a pair I bought off of EBay months ago and dreaded the job. It's always a mucky, oily, messy job. But I tore into the forks. It's much easier having done it 1 or 2 times before. This time I loosened the allen bolts on the bottom of the forks and the spring caps before removing the forks from the bike. Then I removed the wheel, calipers, fender, etc, and removed one fork at a time. Then I drained the oil and dissasembled with little effort.

Problem is always the old seals. They just won't come out without shredding/cutting the heck out of them. Not sure what kind of seals are in there but it looks like Yamaha presses in some kind of seal that never comes out. Either that or the flanges inside the fork tube are part of the fork casting itself.

Anyway, I was a bit worried because the replacement seals looked suspicious. I determined that they were designed to sit on top of the first flange - no circlip involved. I tapped them in with a rubber mallet. They seem cheap, will probably be redoing the forks again, especially if there are any pits on the fork slider I didn't smooth out. But in reassembling and testing, they seem to work so far. I have not air pressurized the shocks. It's nice to have damping again. If these things work, it's always nice to not have oil all over your brake calipers/pads/discs as well.

Only one problem. I lost the little metal bracket that attaches to the square notches in the forks and that holds the tops of the brake pads in place. Drat. Anyone have one they could throw in the mail quick?

Hope to be riding soon. By summer's end I should have some before / after restore pics.

Ben

[Dark Horse]

Hey Ben!

I took care of the fork seals in my venture a couple of months ago. They both started leaking about the same time. The job was a piece of cake!

I rode the "Pack Horse" up to Carey's Cycle in Riverdale and paid them to do it!

It hurt the wallet a little, but I just flat haven't had time to work on my bikes for over a year. At least I've been able to ride this summer.

The Dark Horse is still sitting in the garage being neglected. It's been almost a year since riding her.

Hang in there!

[TopCatGr58]

Hey Ben,

Anyway, I was a bit worried because the replacement seals looked suspicious. I determined that they were designed to sit on top of the first flange - no circlip involved. I tapped them in with a rubber mallet. They seem cheap, will probably be redoing the forks again, especially if there are any pits on the fork slider I didn't smooth out. But in reassembling and testing, they seem to work so far. I have not air pressurized the shocks.

There is a spacer that goes below the seal, but it definitely needs a C-ring above it to keep it in the lower tubes, so IF you left it out, then I definitely wouldn't try pressurizing the forks, or you'll blow those seals out for sure! You really should check the diagrams in the manual, or online in the Yamaha parts fiche to verify what parts go where!? Hope you get some riding in, also hope you don't blow those seals while riding down the road, like Russ at XS East NY recently did!
T.C.

[John]

The best seals that I have found are OEM. I have tried quite a few aftermarket brands and they all sucked! I have had a set of OEM seals for over five years no with no leakage.

[Shuriken]

Bikebandit should thank you guys - you convinced me to buy OEM seals.....

I will take digital pics. I am aware of how the fork is put together. I can see how the spacer is on the bottom, the seal in the middle, and the circlip on top.

What I am suggesting is that the only thing I can remove from the forks are bits of rubber. If the factory seals are a press-fit, I'll never get them out.

Back when I had my 80g about 4 years ago I needed to replace the seals. Ripped into the forks and found the same thing. Easy to remove the circlip. From there it's anyone's guess. If I grab onto the flanges with a pair of pliers, the flanges just bend but nothing comes out.

So - the seals I got look like they are half the height and recess on top of the flange. I have bounced the shocks and they don't leak and I have damping.

But since I'm not interested in blowing out seals, I just spent $70 bucks for a hand grip, a reflector, 2 OEM seals, and shipping.

Now if someone can show me what an oem 79sf seal looks like removed from the fork....

Because as I see it, it looks to me like the flanges inside the fork tube are part of the fork itself, not part of a removable ring of some type.

I hope I'm wrong and that someone can clarify. If I am supposed to remove what sits on top of the spacer it would take some kind of jig to press it out?

Ben

[missinglink]

Getting the old seals out IS a bit_h, but they will come out. I managed to get a very thin screwdriver wedged between the seal and the side of the fork tube (very careful not to scratch the surface) and pried inward. Surprizingly, the metal part of the seal bent inward and I was able to get a good grip on it to pull it out. The second one was much easier. 10 minutes vs 2 hours. to get the seal out.javascript:smilie('')
big grin

[Shuriken]

So the metal flange thing inside the fork tube must be part of the pressed-in seal. I'll see what I can do....

[Winterhawk]

butane torch on the leg works if it's really stuck.

[Snow]

I've always had good lucking using a tire iron to remove OEM fork seals. Have them out in about 5 seconds with no scratching or sweating Note: I believe my tire irons are aluminum or some other fairly soft metal.

[Shuriken]

Great suggestions, guys. I can get to them this weekend - and all HELL is going to break loose! Just kidding.

I have to wait for the Yamaha seals to show up anyway - probably 2 weeks. :-/

Ben

[prometheus578]

Stick the tire iron is a vise pointing upward. Place the upper inner lip of the seal under the iron. Pry the tube downward. Zoot!, out she comes. (Place a rag where the tube touches the iron lest we mar it.

[Shuriken]

Was thinking of a 1/8th stick of dynamite?

[jacksf]

Just did my seals. Originally tried screwdriver and pry bar but, concerned about damaging the outer legs, decided to pick up a Sears seal puller, about $9.

Out they came, easy as pie. Now I can start on my XJ750.

Jack

[superdave]

fork seals

I changed my xj's tuesday 19 th took about 1.5 hrs and 3 beers. I used the old tire iron method(just like prometheus) and used 1 1/2 " pvc pipe to drive the new ones down. called excell a local shop they said 250cc of oil. Hope thats right. rode it home and it was night and day, way better feel ! ps used scotch brite pad to polish tubes,took out scrathes and little dings. Good luck!

[Shuriken]

So I feel stupid, now. Ripped out the fresh aftermarket seals from on top of the pressed-in and stubborn OEM ones. What I thought was part of the fork tube was indeed the OEM seal. With a vise and a hammer claw I was able to get them out. Had the new Yamaha seals on hand (Bikebandit is very fast) and reassembled. Good damping and sealing.

I have another set of 80g forks I gave up on years ago thinking the OEM seal was part of the fork and that I damaged it. I think I'll go inspect them.

Ben