xj 750 seca forks

I started working on the 750rj forks today. First I got the hex key bolt out of the bottom
with an impact wrench while there was still pressure on it. Then pulled out the top circlip,
plug and spring. I pried out the dust cover and removed the other circlip and washer exposing
the fork seal. Now, can I pull the upper tube out of the lower tube with a slide hammer action ?
These forks are a little different from my xj650 maxim and seca forks and I don't want to destroy
anything delicate.

 

If you go slide hammer action, DO NOT slam the inner fork down when resetting or you will crush/disintegrate the wave washers at the bottom of the fork. I've been there/done that.
I had a problem where my bushing got cocked-eyed and jammed under the washer under the fork seal, and I could not drive it out without EXCESSIVE force.

A second option which is messy but will work is to drive it out with oil pressure. Put the damper rod screw in place, remove the other internals and fork seal circlip and fill the fork with oil. (any cheap motor oil will do).
Replace fork cap and air valve. Compress fork in a shop press (or build one using some 2x4s and a car jack...that's what I had handy). The oil pressure will force the fork seal out reliably. Again, quite messy, but guaranteed to work and won't damage the internals.

 

i picture myself stumbling out of the garage with oil dripping off my face

 

I picture myself in divorce court.

 

You guys are a riot. Anyhow I got the two section of fork apart ok. But what I learned that is really valuable, is to take
the hex recess bolt out at the bottom while there is still spring tension against the shaft that the bolt screws into, using
a 1/2" drive electric impact wrench in reverse. The bolts came out easily. Much better this time than jamming a sharpened
broomstick into the back of the bottom shaft and cracking the bolt with a breaker bar. Impact wrench goes for less than
$30.00 on sale at H.F.

 

That's only if you forget to put the air valve back on and are staring at the little hole

I really don't understand why you guys shoot this method down, especially when the "slide hammer" method can do so much damage. I've had the bushing jam itself and spent over an hour trying to drive it out. And I had to disassemble them again after an accident and this method worked so much better.

Honestly, it's only a little messy because you have a little more waste oil and when the fork seal comes out, it'll overflow and run down the fork lower. A well placed hand/towel will keep the oil in place, and you do it over a catch pan. But it's not like oil comes SHOOTING forth when the seal releases.

It's really like the difference between forcing out a brake caliper piston with a grease gun or brake fluid instead of air, you can generate a lot of pressure, but once the object starts moving the pressure drops immediately and the fluid flows out because it's incompressible. Then you just clean up.

 

I was thinking more along the lines of John Wayne in Hellfighters.

Manbot, nobodies hatin' on your method, just poking fun.

 

Jokes. It's just jokes.
I have recommended a similar method myself (and even used it a few times).

 

i guess i'm just paranoid about fork oil. one time i tried to remove the whole anti dive from 750 forks. fork in a vise, no spring, lower fork holes blocked, upper tube held extended, put too much oil in the top of the fork and let go of the upper tube. upper falls into lower, leaving about a 6 inch column of oil in free space.
about this time the fork decides to fall out of the vise. end of experiment

 

I see. Well I can say on a similar note that I do have direct experience with the "leaving the air valve off" (little oil, but boy it travels far) and the "oops I forgot to take the circlip out of the second fork" (<-- not messy but felt dumb compressing the hell out of the fork and the seal not budging).

But both of these combined was better than the slide-hammering for close to an hour and then having to get a set of used fork for the wave washers (which in turn still have to be disassembled ). Again, that was all because the bushing got jammed up but bad bushing or not, the oil method worked consistently.

I still used the slide hammer method on my GSXR fork rebuild a few months ago, but if it had not worked quickly, I would have gotten out the spare motor oil and poor man's shop press.