Stuck fork tube

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Stuck fork tube

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Stuck fork tube - 9/21/2007 11:01:05 PM

bikechump

Posts: 5
Joined: 9/21/2007
Status: offline

Hi everyone, i recently joined the family of cbr owners. I've landed myself a 93 F2 thats i need of attention after being neglected for quite some time. This post concerns a problem ive encountered in the attempt to replace a weaping fork seal. I've searched through a ton of threads and haven't found one relating to my problem. Ive taken the cap that keeps the tension on the spring off, spring is out, ive taken out the allen screw at the bottom of the fork leg out allowing the pistion and return spring out. The problem is that the fork tube will not fully slide out of the leg, its almost like it hits something solid. I've downloaded a PDF service manual but their exploded diagrams and removal procedure are pretty useless as far as explaining things. Thers a piece that i can hear loose between the tube and the leg and from my manual its a OIL LOCK PEICE. I've taken the forks apart on my old bike and never encountered this problem. I hope ive explained it well enough to understand.

Thanks

Post #: 1

RE: Stuck fork tube - 9/22/2007 12:03:40 AM

jahnaboi

Posts: 441
Joined: 8/29/2007
Status: offline

You're replacing the seals cuz they're leaking? I think I have to change my seals as well. If I know what your problem was, i'd help you but I haven't attacked this portion of my bike yet. I'm actually going through a whole rebuilt from the bottom up. Repainting the frame, swing arms, new bolts and everything. So when I venture in this area, hopefully I could learn from you. If anything, viseversa.

Goodluck and welcome.
-Jasper

(in reply to bikechump)

Post #: 2

RE: Stuck fork tube - 9/22/2007 12:44:52 AM

Viking

Posts: 45
Joined: 7/18/2007
Status: offline

Not sure if this is the same exploded view that you've got, but I hope it helps.

Disassembly:
(The numbers indicates the order to perform the dissasembly)

Assembly:
(The numbers indicates the order to perform the assembly)

< Message edited by Viking -- 9/22/2007 1:45:01 AM >

(in reply to jahnaboi)

Post #: 3

RE: Stuck fork tube - 9/22/2007 9:20:01 AM

elmer

Posts: 502
Joined: 12/9/2006
Status: online

I put new fork seals in my 94 this summer. It seems kind of counter intuitive but this is what I think is going on. The tube doesn't just slide completely out. You have to give it a pretty good pull to get them to separate, and to put them back together you'll have to give it a little encouragement as well. when the fork tube is fully extended it catches at the very end. Just give it a good tug.
When I did mine I pressed the seals in with a 4 ton press. I went down to the auto parts store and bought a section of exhaust pipe that would fit over the tube and around the seal. That was the easiest way to do it I found. It seemed almost impossible to get it in there any other way. I used the dust cap as a way to measure if I had the seals pressed in there far enough.
I also used the honda fork oil, which all it really is is 10w automatic transmission fluid. So if you are strapped for cash thats a cheaper alternative as well.
Good luck, and post any more questions if you have them.

< Message edited by elmer -- 9/22/2007 9:22:51 AM >

(in reply to Viking)

Post #: 4

RE: Stuck fork tube - 9/22/2007 7:17:40 PM

bikechump

Posts: 5
Joined: 9/21/2007
Status: offline

hey. I asked someone who knows much more about bikes than i do. After explaining the problem to him he immediatly asked if it was off a honda. Honda are apparently the only ones to choose this brain dead design. Anyways, long story short, we heated the area around the fork seal with a propane torch gave it a good pull and eventually she pulled out. Thought id let you know how it turned out so it'd help anyone else with the same problem.

Thanks for the replys. cheers.

(in reply to bikechump)

Post #: 5

RE: Stuck fork tube - 9/22/2007 8:47:33 PM

Hershey

Posts: 886
Joined: 7/27/2007
Status: offline

Good show! I thought it would be similar to how I explained it on the IR PM... But instead of using a 4 ton jack like Elmer did, I just used the right size PVC pipe and a good rubber mallet to punch her back in place.

Hope to see you around on the F2!

(in reply to bikechump)

Post #: 6

RE: Stuck fork tube - 9/24/2007 7:04:07 AM

lojack349

Posts: 5
Joined: 5/19/2007
Status: offline

I just went through this on my F2. The problem is that the 2 internal bushings are getting wedged inside the fork slider. The smaller bushing wedges inside the larger bushing causing it to expand inside the fork slider. In a perfect world, the smaller bushing will push the larger bushing up as you yank the slider against the fork tube. The bushings eventually work their way up to move the fork seal out of the fork slider. I ended up hydraulically forcing the seal out, by filling the whole assy. with water and pressurizing it with a hydraulic floor jack. This may have been a crude procedure, but it was very effective. Once the seal popped, I could then see the bushing below. I sprayed it thoroughly with penetrant and continued yanking away on the fork tube. Eventually, the bushing freed itself and I could then completely disassemble the rest of the fork. Clymers manual says you can do it while installed in the triple tree steering stem, but I used a 2x12" on the ground as a base for the fork as I was getting it apart. The 2x12" gave me a good base to pull and push off of. You will have to pound the fork down after each pulling stroke due to the wedge effect of the bushings. The 2 bushings were ruined from being wedged against each other. The oil lock piece was also roughed up so it had to be replaced as well. Don't give up. It may seem like it will never release, but eventually it does.

(in reply to Hershey)

Post #: 7

RE: Stuck fork tube - 9/24/2007 6:43:53 PM

bikechump

Posts: 5
Joined: 9/21/2007
Status: offline

Both slider bushings ended up getting deformed somewhat so i'll be replacing those as well as the bushings on the top of the slider under the seal. I figured i may as well "fork" over the money for some new parts while shes apart. I see the slit in the bushings and i assume they just slip over the fork tube and slide down into the fork leg. Anything out of the norm to be expecting?

p.s. wicked prank hersh. i laughed so hard after seeing that pic of his tail light. brilliant

(in reply to lojack349)

Post #: 8

RE: Stuck fork tube - 9/25/2007 12:00:23 AM

Hershey

Posts: 886
Joined: 7/27/2007
Status: offline

Well, unfortunately he got ME with the sticker lol! I wrapped his bike up, there's more in store though so stay tuned haha...

(in reply to bikechump)

Post #: 9

RE: Stuck fork tube - 2/25/2008 9:57:54 AM

jahnaboi

Posts: 441
Joined: 8/29/2007
Status: offline

Hey bikechump, I'm experiencing the same problem with my fork as of the moment. To what extent did you heat up the fork tube? Till it was glowing red? I've been going at mine for a while and I can't seem to get the damn thing out. I've removed everything from the back up ring to seals, all that's left is the bushings, fork tube and slider. I tried things from my car, to hydraulic jack. Elmer, if you don't mind me asking, how did you use a hydraulic press to remove the fork?

-Jasper

(in reply to Hershey)

Post #: 10

RE: Stuck fork tube - 2/25/2008 10:50:53 AM

elmer

Posts: 502
Joined: 12/9/2006
Status: online

Jasper, I didn't use the press to get anything apart. I used it to press the new seals in. I remember reading through at least one of your threads where you were describing how difficult things were for you. Maybe my experiences were different because I have a 94? Either way, with my forks out of the triple, spring removed, everything out, all I had to do to separate the fork tube and leg was to hold them in each of my hands, and give a few solid jerks to separate them.
After that I put them back together, slid the new seal down the fork tube, put my section of exhaust pipe on top of the seal and gingerly used the floor press to push on the exhaust section pressing the seal into the fork. Then I put the springs and oil in, tightend the top and reinstalled. Nothing was nearly as difficult as what you guys are describing, fortunately for me...

good luck.

(in reply to jahnaboi)

Post #: 11

RE: Stuck fork tube - 2/25/2008 11:06:27 AM

jahnaboi

Posts: 441
Joined: 8/29/2007
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If you didn't know elmer, my bike is a 94. =P But I don't know why my left fork tube is acting up on me... my right came apart with close to no effort. Its just my left one... Right now I just tried heating it up with a torch... not till it was glowing red but till it was pretty hot. I'll try glowing red now... wish me luck...

-Jasper

(in reply to elmer)

Post #: 12

RE: Stuck fork tube - 2/25/2008 11:52:10 AM

jahnaboi

Posts: 441
Joined: 8/29/2007
Status: offline

So I heated it up till my forks turned orange (keep in mine my forks are factory black [galvanized?]) so its not the paint turning orange its the metal... I placed it back on the lower and upper triple on my bike, put the axle bolt in the hole of the lower fork leg, bolted it down, and slid it up, then in a hammer motion slid it fast hard and hella fast... kept at it till I got aggravated so I left it fully extended then started hammering it downward with a rubber mallet as hard as I could... The bushing... never moved. WTF. This is ridiculous, I went from using my car... to a hydraulic jack, to using a blow torch and a rubber mallet (the big one) and nothing is working guys. **** it. I give up.

Score: Bushings - 3 Jasper - 0

=(

< Message edited by jahnaboi -- 2/25/2008 11:58:00 AM >

(in reply to jahnaboi)

Post #: 13

RE: Stuck fork tube - 2/25/2008 2:12:59 PM

elmer

Posts: 502
Joined: 12/9/2006
Status: online

Man that sucks! I forgot that yours was also a 94. I'm reasonably sure that the forks for the 94 are different than the previous F2's. I guess at this point all I can do is start shopping for another fork!
It obviously seems like your bushings are binding inside the fork tube, so yeah, it would probably be a start to drive the fork tube back down to try and get things loosened up again. Then basically start over I'd think. Trying to turn the fork tube and rotate the bushings inside the fork leg and then try pulling them apart. The amount of force used to separate these pieces should be substantially less than what you've been using with no success.

I definitely sympathize with your situation, there's nothing worse than when a project comes to a complete standstill. Good luck man.

(in reply to jahnaboi)

Post #: 14

RE: Stuck fork tube - 2/25/2008 2:24:58 PM

jahnaboi

Posts: 441
Joined: 8/29/2007
Status: offline

Honestly, if I had the money to engineer a machine to pull this shit apart I would, but I don't know if someone has make an inverted hydraulic press. Rather than pressing (pushing) it pulls. Does anyone know if any shops have created such a machine?

-Jasper

(in reply to elmer)

Post #: 15