550 Maxim fork oil replacement

I'm planning to replace the fork oil on my bike. Questions...

Access & disassembly
My Clymer manual describes a fairly involved partial disassembly of the handlebars, mirrors, etc. The pictures show a Seca, I think. This does not appear to be necessary on the Maxim. Seems like there's clear access, but I've never done it before so maybe I'm not understanding a clearance issue related to using a specific tool???

Also, I'm a little hazy on the actual process of getting that wire retaining ring out that holds the cap bolt in place.

Corrosion
On one side I have a little bit of surface rust on top of the cap bolt and some light corrosion on the inside of the very upper edge of the tube. I assume that, since I am not planning to disassemble the forks at this time, I should be pretty careful about how I clean that up so as not to get any bits of crud down inside the tube. I'm thinking that I'd remove as much as I can before taking the cap bolt off, then after it's open I'd either just wipe it out or use something like a rubbing compound that will adhere to the side of the tube and could be wiped out when finished.

Capacity
The service manual says that I should refill with 9.2 oz of SAE 10 or equivalent oil. Is that the combined capacity or is that amount needed for each tube?

Replacement parts
I'm planning to replace the drain screw gaskets, cap bolt o-rings and circlips, but I'm hoping to reuse the cap bolts themselves. If anything else is a "must-replace" item in this procedure, let me know.

Thanks!

 

Fork oil capacities and recommended weights are as follows. The amounts listed are per fork tube:

XJ550 Maxim: 272cc or 9.20 fluid ounces. 10W fork oil.

10W fork oil is not the same as motor oil!!

A small pick or flat blade screwdriver will serve to get the retaining rining "started" out of its groove, and then you just "wind it out"........but that's easier said than done, because typically you have to keep some downward pressure on the cap bolt while you are performing this magic trick....

 

The Seca and Max use the same handlebar; you don't REALLY need to pull the bars as long as your fork caps are free, you can push them down far enough with something skinny enough to clear the bars.

That being said, it's MUCH EASIER if you simply de-mount the bars and pull them back and set them on a bundle of shop rags on the tank. That way you can get at everything and have a little room to work.

 

I finally started in on this job. Is it possible that rust or corrosion could be preventing the cap bolts from moving? I'm not a really bulky guy, but I'm pushing down on the top of those things for all I'm worth using the end of a crescent wrench and I don't think they're moving at all. How far down should I be able to depress them?

 

welcome to the world of pain i experienced a few months ago, as i know other members have as well.

use KROIL. bigfitz has been letting us know about this beautiful little product. its a really strong penetrating oil. You can get 2 big spray cans of it for $12

http://www.kanolabs.com/google/

The stuff works great, when the caps finally came out they were spotlessly clean.

What i had to do was kroil them for about a week (2 or more applications a day), and grind the inside of the fork tubes down with a strong rotary tool, and use my body to compress the front end before they finally came out.

 

Thanks for your response, lopezfr2. By the time you posted I had answered my own question. I used some penetrating oil, but the trick for me was taking a socket just little smaller in diameter than the bolt and tapping that with a hammer a few times. That knocked the bolt loose from the rust and corrosion and I was then able to compress it with strong pressure. My guess, for the benefit of the next person who reads this, is that you can depress it about 3/16-1/4".

After working on trying to get that clip out with the help of a friend, we gave up and I sent him home. I then looked and pondered, scratched my head for awhile trying to imagine how I might secure a harmonic balancer puller or something similar, and then actually came up with a pretty simple but effective idea that others may even find useful.

I took a piece of 1/2" galvanized pipe and tightened it into the handlebar mounting brackets. I then took an 18" breaker bar for 1/2" sockets and used it as a pry bar. I added a 1/2" to 3/8" adapter for just a little more length on the drive end. I put that on top of the fork cap bolt and pulled up on the breaker bar using the pipe as a fulcrum. See attached image. With the other hand I used a small screwdriver and/or a little hooked dental pick to pull the clip out. The key there was to pry the clip up in the middle, not out near the ends.

WATCH OUT WHEN THE SPRING RELEASES!

So I've figured out an easy way to make this a one man job. However, this story doesn't have an entirely happy ending. There is a reason that the manual says the bike should be on the center stand. Just as I was about to congratulate myself for how clever I was, the spring released on the second fork. Now that there was nothing to keep the forks expanded, the bike, which has been on the kick stand, suddenly dropped down and fell way from me landing on its right side as I stood there helplessly. Here's a list of the damages as far as I can tell...

- new right side mirror smashed
- brake lever scraped
- newly repainted master cylinder cover (or just-rebuilt mc) scratched
- front turn signal smashed
- new rear turn signal scraped
- rear brake pedal bent...
- ...into clutch cover that I recently replaced, repaired, and spent a LONG time polishing. Clutch cover is dented and I think cracked and leaking.

There might be more but those are the highlights. Went from being very pleased to very sad very quickly.

 

Great idea, and don't beat yourself up too bad for not seeing that coming....you aren't the first, nor will you be the last to hurt their bike while getting as lesson in suspension vs kickstand physics.

Did the same thing to my '81 Gold Wing when I went to repair the leaking rear air shocks...for some reason it didn't occur to me how far it would drop if all the air was released. Did the same thing, flopped it off the stand when it dropped...

 

You will soon come to realize that there is generally a reason for everything it says in the manual. Sorry you had to learn the hard way.

(The manual also says to disconnect the battery before beginning any major work, who bothers, right? One good shower of sparks teaches that lesson...)

Maybe I can brighten things up a tad. If your clutch cover is truly cracked and leaking, I can hook you up with another one. I have a couple that have been repaired from similar tipover damage; you'll need to do some polishing. I'll see if I still have your email address somewhere, or send me a PM.

Oh, and I can't take credit for KROIL, it was another member who recommended it to me after I spent 9 months fighting the exact same problem-- rusted stuck fork caps.

 

Thanks for your support, guys. It does help.

Thanks, too, Fitz for your generous offer. I'll respond privately after lunch when I get back home.

The old oil was very black and thick on both sides, but there didn't seem to be much in there. I guess that's why the forks were so soft. Last night when I went to bed the right fork had stopped draining.There was a bit of rust and gunk inside the upper tube and on the spring. I had poured some new oil into both forks to flush them out a little. I probed the drain hole to make sure that was clear but it didn't seem to help.

I don't know if time will make a difference or not. Should I try mixing something else in there like Seafoam or MMO? I hadn't planned on taking them off and replacing the seals at this time, although I guess that's not entirely out of the question. I have to admit, though, that my enthusiasm for cycle repair is not currently at an all-time high...

 

Don't dump anything else in there except more fork oil. If the seals don't start leaking now that there's the right amount of oil in them, just change the oil again real soon.

If they don't leak, don't worry about changing the seals... yet. They'll let you know by beginning to weep.

 

What I'm saying is that nothing is draining out of the right fork with the drain screw still removed. It started to drip slowly when I first opened it and then stopped after awhile. I can see the oil that's still inside the tube. The left one emptied out the old stuff and the new oil I put in but the right side is plugged somehow.

 

Urk. Do you have the front of the bike supported now, like maybe a jackstand under the front crosstube?

Get a helper, and operate the fork. With the caps out the springs will come up and probably stop against your ad hoc handlebar.

Be sure you have a catch pan situated properly to catch the oil if it "pops" free it will squirt out the tiny drain hole with quite a bit of force. You might want to put the plug back in the other side for now.

For future reference: If all you're doing is changing the fork oil:

-make sure the top cap plugs are free. Don't remove yet.
-remove one drain plug, place LARGE catch pan, pump forks. The slower the better, it's gonna squirt big time anyway.
-replace drain plug, remove other side, repeat.
-THEN support front of bike and remove caps. With caps and drain plugs out, let forks drip for a while.

When reassembling: Use new drain plug screw gaskets; they're probably mashed into the holes in the forks and often split. Usually need to be dug out.

Add fork oil slowly, it can take a few seconds to run down around the springs; if you simply dump it in you could get an overflow.

 

No, I don't have the front end up at this time and I removed the springs to inspect and clean them. 10-4 on the oil pressure while pumping. I have new drain screw gaskets, cap O-rings, and clips on hand and ready to go.

Question: How can 9.2 oz of oil overflow in those big tubes? Does the oil level stay down below the top of the lower tube?

 

I have a stupid question at this point.

Would it be possible to remove the fork legs from the trees, drain them, then invert them and fill so you don't have to mess with the caps?

I've wondered about this. I've never done fork work. I REALLY don't wanna mess with those caps and air seals, as they hold fine now, surprisingly.

But I would like to change the oil...

 

No the overflowing I was talking about would be if you didn't have the springs out and tried to dump all the oil in at once. It takes a minute for it to run past the springs is all; you won't have that problem. All you need to do is pump the fork to expel the old oil.

In theory, I suppose. But the drain holes are only like 3mm in diameter; refilling the forks through the drain holes could prove interesting at best if possible at all.

If you have air caps, then you probably also have threaded-in caps rather than the push-em down kind, so yours is a different challenge.

 

I got the job done this afternoon. It feels like a different bike, although, I haven't ridden it yet of course. It went back together very easily and I'm not a bit afraid to tackle this again. The pry bar system makes all the difference in the world. Thanks again for your help, Fitz.

I also took off all the broken stuff and made a list. Cathartic, actually.

 

What I was kicking around was the idea of compressing them with some kind of device of my own design, hooking an air-tight vinyl tube or something to the drain hole...perhaps by finding a bleeder screw size that will fit the drain holes or something, and letting it draw in the required amount of oil as I allow them to slowly decompress. I could measure by drawing from a reservoir of known measure, with graduations on it.

Like I said, I don't really know how they work exactly, but it seems possible.

Think it might work?

 

Once again, theoretically it might work.

However, what you're proposing is a lot MORE work than just removing the caps and doing it right.
Honestly.

 

Well, I have a strut compressor that could easily be adapted to do the compressing, and removing the tubes from the bike is no big deal...

 

Got everything that was damaged in the fall fixed on Thursday and was able to take a longer ride on Friday. Looks like the fork seals are leaking pretty badly. Not surprising considering how little oil there was in either one.

 

No surprise, really. Fork rebuild is FUN, now that the hard part is vanquished (the rusted-in caps.)

 

I've been reading some threads on that project and the only question I have has to do with the specifics of the dampened rod holding tool. As I understand it, you just need to hold it on the inside of the lower tube to keep it from twisting while you remove that allen head bolt, right? Gamaru made reference in his tutorial to the use of a spark plug socket turned upside down? Does the dampener rod have a hex head or is he talking about using the square drive hole on the socket?

 

There's a 19mm hex down there; you need a sparkplug socket with a hex cast into the bottom of it like a lot of them have. The hex on the bottom of the sparkplug socket effectively turns it into a giant allen key.

 

Now I get it. Then you can use a bunch of extensions snapped together to reach down inside the socket through what would normally be the working end inserted into the socket's square drive hole. Beautiful!

 

Edzachary! You may need all the extensions in your toolbox...

 

If that's not a metaphor for life, I don't know what is...

 

Hey, I actually only needed all but one of my extensions!

This is now focusing on a fork rebuild not just oil replacement, but I'm not sure whether I should start a new thread. I guess I'll continue with this one.

I'm wondering about the wear on these parts. They don't look too bad to me, but I'm not sure how critical it is either.

 

No show-stoppers there; clean 'em up and re-use.

 

That's what I like to hear! Thanks, Fitz.

 

I've got the parts now to rebuild my forks (thanks to the usual quick order turn-around from chacal) and am hoping to at least get started today. My service manual says to align the top of the upper tube with the top of the upper fork bridge. Before I took them out, however, they extended about 3/8" past the top of the bracket. By that, I mean past the part of the bracket that they slide into - the "clamp."

Which is correct?

 

That's a PO's quick-n-dirty lowering tweak. Supposed to be flush.

 

I'm not quite sure which way the fork springs go back in. My Clymer manual says that the "smaller diameter" end should be at the top. This doesn't make any sense because the diameter is the same on both ends. I think that's supposed to mean the end where the coils are closer together, but I'm not positive.

Thanks.