How am I supposed to remove this fork bushing on an inverted fork?

[squiggy]

I'm slowly advancing on my inverted (upside down) fork conversion on the Kat. So I took apart my donor forks, 1st Generation Yamaha R1 Kayaba (KYB), to get an understanding of one, upside down forks, and two, cartridge forks. Everything came off and out of the fork like normal conventional forks except the upper bushing.






How am I supposed to get this bushing out? It looks like it's recessed into a slot. I've already tried banging on it with the fork stanchion, using a wood chisel and using a pick-hook from Harbor Freight with no success.

I've done quite a bit of research on Google using "KYB, Kayaba fork, upside down fork, cartridge fork" as keywords with no success. However, what I did find is some "how-to's" that did show upside down forks with that very top bushing exiting with the rest of the internals. My guess would be that it is from a Showa fork.

I've noticed that the Yamaha fork and a damaged set of Kawi ZX14 that I bought, the forks are of the same configuration. With both forks, the bushing stayed mounted to the fork body. There is no recessed slot on the stanchion itself for this bushing. Both manufactures do use KYB forks. Even though this How-To article on Suzuki TLR fork shows the bushing coming out of a KYB fork. R1 on the left, ZX14 on the right.





So now I'm stuck trying to figure what I can do to get that bushing out.

Any ideas?

[Tmod]

Where did you get a new bushing from? As far as RT & I know they are not available without purchasing a whole new outer tube, I am going to suggest that they just be left alone as all you will do is damage a part that cannot be purchased seperately.

Tmod

[squiggy]

Where did you get a new bushing from? As far as RT & I know they are not available without purchasing a whole new outer tube, I am going to suggest that they just be left alone as all you will do is damage a part that cannot be purchased seperately.

Tmod

I haven't bought the bushings yet, I'm just gutting them to learn about cartridge forks.

That's crazy that KYB expects a bike owner to replace the whole outer tube just to get new bushings.

I was giving a link to an R1 service manual and it looks like Yamaha shows that the outer tube bushing can be replaced, but nothing on the inner tube bushing.

https://www.scribd.com/doc/2634179/yzf-r1-manual

[Black_peter]

I'm with T on this.. If it looks good and there is no damage?

Just step away...

[Tmod]

I haven't bought the bushings yet, I'm just gutting them to learn about cartridge forks.

That's crazy that KYB expects a bike owner to replace the whole outer tube just to get new bushings.

I was giving a link to an R1 service manual and it looks like Yamaha shows that the outer tube bushing can be replaced, but nothing on the inner tube bushing.

www.scribd.com/doc/2634179/yzf-r1-manual

If you can locate the bushings let me know, RT would like to know where to get them as well.

If you REALLY want to take that bushing out get me the ID of the tube that the bushing presses in to and I will make a little uninstaller for them, However I can not say for sure that the bushing will be usable afterward.

Tmod

[squiggy]

If you REALLY want to take that bushing out get me the ID of the tube that the bushing presses in to and I will make a little uninstaller for them

If you believe that the bushing is pressed in, then the next step I'll do to see if it is recessed or just sitting there is to cut the fork tube a couple inches above and below that bushing. I'll get the inside diameter measurement and see if it is in a slot. If it's in a slot then there can be no way to press or hammer out the bushing.

[diavolo]

Just a word of caution regarding those bushings - they could very well be interference fit units - you'd wind up wrecking the outer tubes trying to hammer or press them out. Only way to safely remove them (if they are indeed interference fit) would be to warm up the outer tubes to expand them, and simultaneously "shrink" the bushings with some dry ice (best), or ice cubes (in a pinch). Bushings will then press out of the tubes easily. Install is same as removal: heat outer and cool inner.

[Tmod]

If you believe that the bushing is pressed in, then the next step I'll do to see if it is recessed or just sitting there is to cut the fork tube a couple inches above and below that bushing. I'll get the inside diameter measurement and see if it is in a slot. If it's in a slot then there can be no way to press or hammer out the bushing.

No need to cut anything, Just measure the ID where the tube actually goes into the lower and give that dimension to me. The bushing can be removed my point is you can't buy a new one to install in it's place. Look at the manual and you will see that is not even mentioned in it.

Tmod

[squiggy]

Just a word of caution regarding those bushings - they could very well be interference fit units - you'd wind up wrecking the outer tubes trying to hammer or press them out. Only way to safely remove them (if they are indeed interference fit) would be to warm up the outer tubes to expand them, and simultaneously "shrink" the bushings with some dry ice (best), or ice cubes (in a pinch). Bushings will then press out of the tubes easily. Install is same as removal: heat outer and cool inner.

Thank you, good to know.

No need to cut anything, Just measure the ID where the tube actually goes into the lower and give that dimension to me.

I can't remrmber right now but I thought the inside leg has a taper to it, I'll have to check when I get home. This particular fork is damaged, so cutting it is not that much of a problem. I'm doing my R&D with this damaged fork so I don't mess up my good forks.

[squiggy]

OK, so I cut the fork tube, weeee sparkles. I measured the tube above the bushing and the tube below the bushing.

First pic is looking at the tube from the oil seal/dust seal end. I can see and feel a ridge in this pic. There would no way to press out the bushing going in this direction.





Link to much larger crop.

http://farm3.static.flickr.com/2667/3813805522_c925f1e308_o.jpg

This pic is from the top fork cap. In this pic, there is no ridge for the bushing to come into contact with. So if pressing out the bushing, it would have to go in this direction, upwards.




A link to a much larger crop.

http://farm3.static.flickr.com/2619/3813805644_be5bda3ca8_o.jpg

Inside diameter measurement from the below the bushing as if mounted on the bike.





Inside diameter from above the bushing as if the fork is mounted on the bike.







This is going to be my penny-tech route of avoiding buying new springs for now. For those that read my thread on cutting fork springs, here are the two pics of the correct length spring and one that is 20mm longer.

I figure I could trim the preload spacer to compensate for the longer spring.








And lastly a pic of the different forks I've been researching.

Left to right:

1999 Yamaha R1

Kawasaki ZX6, if I recall correctly. I don't remember the exact year but it is a late model.

????, I don't even remember what that fork is.

Kawasaki ZX14.

Our Post Katana fork, I believe it is from a 750.

Suzuki TLR fork.


One thing to remember on the height difference, is with the Kat 750, the actual mounting point of where the top triple clamps to the forks is about 1-1/2 inches below the very top of the fork. The very top of the fork is where the handlebar plate mounts to the triple. So a donor fork does not need to be as long as the whole fork.