XJ750J with # knobs on top...replacing seals...

I was looking into replacing the oil and dust seals on my forks. After reading through the haynes manual on it, it appears that this particular model is a pain to do. Has anyone here done this type of fork for the seals? Any help would be appreciated as I don't want to take it to a shop.

 

http://xjbikes.com/Forums/viewtopic/t=41895.html
http://xjbikes.com/Forums/viewtopic/p=3 ... tml#394634
http://xjbikes.com/Forums/viewtopic/p=159288.html

hope this helps.

 

None of those posts showed the 750J which has no antidive and a stiffness adjustment knob on the top of each fork and also has air assist. According to the haynes manual, this model is a pain to do. Totally different than the other styles and requires special tools. Was hoping someone here has already done this type.

 

They ALL require a "special tool" which is simply a reallllly long 19mm hex bit that can be constructed or substituted in many different ways.

Can't help otherwise, all of my bikes have "simple" forks.

 

I just did mine on my '82 XJ750J Maxim.....not complicared at all

 

The only differnce between your forks and mine:

I have anti-dive (lots of little parts, but easy to work on)

I do not have the preload adjuster caps ( essentially a detent screw that pushes down on the fork spring)

We both have air assist.

The Haynes manual overestimates how difficult woking on those forks is. If you've done fork seals on any other machine you can handle the ones on the J. If you haven't ever replaced fork seals then you can still handle the job, but it will take a few minutes longer to get the job done.

 

block the front end up to take the weight off the front wheel. take off the number caps. the rest of this is from memory so....
take out the drain screws let it drain good but you'll still make a mess. as you unscrew the plugs on top try to hold them down as you turn them, when they get to the end they can pop out and bugger up the threads. that's all you really need to watch out for. maybe when you start put some penetrating oil on all the bolts and on the clips under the dust caps and loosen the axle,brakes and fender

 

Having a 750J, and having done my seals with no prior experience, I can say that is not the case. It's been quite a few years, so I can't say for certain, but I don't think I even bothered with the Haynes -- it's that uncomplicated.

 

I'm on it. I'll post if I have any issues. Thx all.

 

Take a look at these threads...not complicated at all.......i just did mine......

http://www.xjbikes.com/Forums/viewtopic/t=44702.html

Or

http://www.xjbikes.com/Forums/viewtopic/t=44583.html

 

I finally got brave and pulled the forks. I made a tool with the upside down spark plug socket and a 3/8 to 1/2" adaptor that fit right in the socket. After pulling the tubes apart on the 1st 1, I was able to get the dust seal to come off. The oil seal, I pulled the clip, but the seal won't budge. Is there a trick to getting it out?

 

try a little heat on the outer tube, get it pretty hot then just slam them apart a few times.
you can try running a screw into the seal just to get it cracked loose but you run the risk of nicking the chrome or seal area of the lower, this would be a last resort

 

put a screwdriver underneath them & pry it out......or take to local bike shop...they will pop them out for a six-pack of beer or free....thats what I did.....I had them put in the new oil seal...free of charge.....

 

Dont use a screwdriver or drill. As mentioned earlier, slam them apart.

 

There is no way to get a screwdriver under the oil seals without causing damage to the fork leg. You can get one under the dust wipers, but not under the oil seals.

If the seals are so stuck that you can't get them out by using the fork leg as a slide hammer then the next best option is:

1. Put the damper rod bolt back in, along with the drain screws.

2. Fill completely with oil, and replace the cap.

3. Place the fork leg on the garage floor, in a sandwich that consists of:

Part A. an immovable object (wall)

Part B. a scissors jack (you will need to use a socket so the jack will only press on the fork cap, and not on the adjuster knob).

Part C. another immovable object (car tire, attached to car)

4. Extend the jack so as to partially collapse the fork leg.

5. Clean up the mess after the oil seal pops out.

 

use a small claw hammer like your trying to remove a nail, put cardboard between the hammer and the top of the fork.

 

Like I said....take to local bike shop & they will probably pop them out for you free of charge......if forks are off bike & disassembled & fluid free, & you are down to just seeing the exposed oil seal, then they will most likely will pop them out for you

 

Well, the seal replacement was as easy as you all said. What a difference new seals make. No dive when breaking now. I had a piece of pvc pipe that popped the seals right out. I went with 15 weight oil as I ride 2 up mostly. Nice n stiff, the way I like it.