Help!! Critical fork problem on 2K CR250!

Racers Edge

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Jan 22, 2001
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Background:
I'm rebuilding the forks on my 00 CR250 and have gotten everything out to where the two large tubes just need to be seperated. I'm doing this at a local Honda dealership so I have access to manuals and the mechanics and special tools. My problem is I can't get the two tubes seperated! The instructions say to jerk them apart once you've removed the dust seal and the oil seal clip ring which I have.

Heres everything I've tried to get them apart:
1) Just jerking them like the book says.
2) Banging them apart by sticking a peice of wood on the larger end and trying to seperate by banging on the wood with a hammer while the grey bottom is in a vice.
3) Heating the tube where the seals are and jerking on it while other ends in vice.
Sticking two bottle jacks inbetween them and trying to sperate with wood and other special round clamps soas not to damage ends of the fork.
4) Digging away at oil seal to try to just remove seal.
5) Using seal driver to drive seal back in and then jerk it apart.

Results:
The harder I try to get it out the more stuck it seems to get when seperating. I then have to use a block of wood and hammer to telescope the forks back in when jerking it. I called a suspension tech guy for the heating up trick. This is also happening with both forks which is really odd. The suspension guy says he's never had this on 00 CR250 forks before (these are Showa's).


Anyways if anyone has any ideas for me it would be much appreciated! I'm taking the forks with me to the suspension guy to see if he can rig something up monday if I can't get it figured out tomorow. Thanks!
 

KiwiBird

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Jan 30, 2000
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I use lots of heat - use boiling water if you're worried about damaging anything - get the seal area hotter than you can touch and allow the heat to penetrate the tubes.

The slide hammer method seems to work best for me, just enough force so that you don't push the outer bush over the inner one - that's when they "stick". Try 90 degree alternate side loading the tube in the center when you slide hammer them as this sometimes will get the bush moving.

Nothing magic here - I was trained by a British bike mechanic and understand "necessary force".

Good luck.
 

Racers Edge

Member
Jan 22, 2001
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I tried heating it up already yesterday and no luck. Today I tried hooking it up to a engine hoist with the two special round clamps I have and pulling it apart, still no luck! I may just have to bring it to BBR Motorsports or Devol Racing or Pro Action on monday and see if they can do it! :-(
 

marcusgunby

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Jan 9, 2000
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I have never heard of this problem before-im guessing the 2 bushes have gone inside each other and the more you pound them,the more they jam in harder-its even more strange that both have the same problems-tell us what you find.
 

Racers Edge

Member
Jan 22, 2001
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After inspecting the fork I had in the hoist closer, it did slide out quite a bit yet the oil seal did not budge and is in the same position in the outer tube. I had to put my whole weight almost on the chain of the hoist though and didn't want to break anything so figured it would be safer to just take them to the suspension shops on monday. Hopefully it wont be o the point where I have to cut the piston tube in half and push it out the other end. atleast then I may only have to buy one tube for each if I haven't already done damage to the insides of the outer tubes.
 

marcusgunby

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Jan 9, 2000
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I would be surprsied if a shop can do any more than you have tried-i would try to get the seals out again-then you can see whats holding the bushes in-also i just thought-how about trying to push the inner fork tube out with some kind of driver-from the inside of the outer leg?

 

Ohh just had another idea-the fork leg bottom assemblies actually unscrew-they have a grub screw you need to remove 1st and a bit of heat will help brake the threadlock-then unscrew the bottoms and push the tubes back through the opposite way.
 

Racers Edge

Member
Jan 22, 2001
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hmm are you sure you can take them apart like this? there is a tiny about 3mm diameter hole in them, that must be one small screw holding it in! I'll have to clean it out and look in it tomorow. I always thought the tubes were pressed onto the ends, which would make sence seeing as they would be under constant pressure and not want to seperate elsewise.
 

marcusgunby

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Jan 9, 2000
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They definatly unscrew-you need to do this to have then hard anodised.I think you need to drill the grub screw out-talk to a local tuner as i bet they have done a few.
 

Bud-Man

Member
Dec 5, 2000
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Another thing to try if you can't get the aluminum collar off: try scraping around the outside of the oil seal with a dental pick or other suitable item. I've seen oil seals stick to the aluminum and sometimes there is some rust from the retaining clip that keeps the oil seal from coming out. The big problem now is that the bushings are telescoping over each other and this expands the outer bushing.
 

Racers Edge

Member
Jan 22, 2001
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Derek over at BBR was able to get them apart. The one I hadn't tried the engine hoist on was fairly easy, we just heated it way more than I initially had and jerked on the sucker for a few minutes and it eventually gave. The other was a little more diffcult. We had to use a floor jack and prop it under a staircase to telescope the tubes back together. We then tried heating and jerking. It took alot of time and heat but this one eventualy gave also. There was no teflon left on the bushings though where the other had about half left the teflon left on. Surprisingly the tubes are still in good shape and were not damaged by the process and are reusable. Derek says that's definately the worst he's ever seen them and most he's ever had to heat them to get them apart. Luckily they had some bushings in stock so tomorow I'll be able to get them back together and go riding yet this holiday! Thanks for the help guys! I guess the best solution still is a lot of heat and just jerk on it like the book says.
 

marcusgunby

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Jan 9, 2000
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Its very strange as normally all i do is a few litres of boiling water and a few short sharp jerks-jer gave me the tip of small fast jerks-not long jerks-no funny coments you rude minded suspension weirdos:)
 
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