fork oil change.

I was wanting to go to a little heavier oil in my forks, but I am not quite sure how to change it. I know, I need to get the XJCD. Anyone be kind enough to give me a step by step? My bike is a 81 650 maxim.
:?: :twisted:

 

Easy: 1) Drain 2) Refill with proper amount
Okay now a little more in depth - it's reccomended you take the forks off the bike, but you can do this with the forks on the bike -- however, the frame needs to be supported, because as soon as you remove the top caps there's no tension and the fork will want to compress (bad thing).
You need to remove the spring caps from the tops of the forks. Take of the black rubber caps, you'll see a metal plug. You need to push that down, and you'll see a metal C clip in a groove that's holding it in -- you need to remove that clip. Then let it out slowly --SLOWLY-- big spring under pressure in there. Once done, you'll find the drain screw at the bottom rear of the fork. Put a pan under it, remove the screw, let it drain. Note that if you've got the forks off the bike, you can pump them here to assist in draining.
Once that's done, you just reverse -- put drain screw back in, refill with fork oil (weight & amount I don't have right now), replace the metal plug - hold it down & replace the metal C clip in it's groove, let it out --slowly-- then put the rubber cap back on.
There ya go - the whole shebang....

 

I'm not sure if the 81 had the air assisted forks or not, my 82 does.
If it has air assisted forks you don't have to remove the top plug. It will have an air valve under the plastic cap. All you have to do is remove the air valve and fill from there. If not proceed as above.
The refill capacity is;
262cc. (9.24oz.) per fork

 

like the fella said- youll need to support the front of the machine. & was able to catch the small frame cross piece between the ex pipes.
when you pry the rubber caps off, if its rusty in there, hose it down w/ penetrating oil over night. The snap ring is actually below the top of the cap youll see in the hole, youll need to push down on that cap til you see the wire clip. One person can do it, but its easier w/ 2. Factory recommonds 10/30 motor oil.

 

My 81 650 does not have the air adjust forks... I think that was on the 82+ models.

 

My '81 hasn't the air adjust either. Rust is common under that rubber cap so be prepaired. Be sure to clean out as much rust as you humanly can (chemical conversion compounds are great for this application, try Permatex Extends) and it the exposed parts with the aforementioned conversion coating. Be ready to replace the spring clip. I went to internal SAE snap-rings from the hardware store because the dealer wanted dang near $13 a piece for the little blighters and they are a lot easier to remove. If you were handy with a drill press I guess you could modify for air adjustment, but that is where I get off. I've no idea if it would work or if the valving isn't set up to work with it. Get yourself the XJCD and the Haynes, you'll be glad you did (I'm working off of the more is good theory here, I don't have the CD yet, waiting for the three CD release next month). Rich has you set up on quantities and I'll suggest going with at least 15 weight oil if not 20 because the damping on these models is a little light. Good luck!

 

Well, I dug this one out of the grave because I wanted to make sure I wasn't crazy.

My manual isn't too explicit about where to put the fork oil once drained, so I just unscrewed the schrader (sp?) valve on the top of my 650 with the XS1100 forks. Once that valve was off (really small opening), I pumped the oil in.

My front end is really soggy though, so I took it to the shop and asked what he thought... He said - you dissasembled the forks to put the oil in, right? Me: no! Him: you have to put the oil in the right place, air goes in that valve, not oil. Me: CRAP!

When I get home and read this post, I think I did it right by putting it in there. Am I correct?

Also - on my X, I take the caps off with the valve on it, there is an inner tube, and an outer tube. Does it matter which tube I put the oil in?

BTW - both bikes when I added oil, I ensured that the new oil drained out the drain before I added more. So I assumed it was going to the right place since the new oil was draining from the same place as the old oil.

If this dealer is wrong about this - I am going to have to stop taking their advice!

 

The air valve do lead to the center of the forks where some of the oil sits, so you are fine on that account.
You must be careful not to put too much oil in the forks.
Too much will cause the seals to blow out and will cover the front end in fork oil.
I recommend taking out the springs, via the upper caps.
Once out you can pump the front end to remove all the oil trapped in the valving.
This will take a few pumps.
Or, if you have the air assist, you can do what I did.
First bleed off the air, then open the drain plugs.
When the oil starts running out slowly, hit the fork with some air.
This works great, but will also take a few applications.
Also watch out, the oil will come out pretty fast.
Once empty, replace the drain screw, and disassemble the fork tops.

Nachoman

 

The only front air assist systems I've played with were off an '82 Honda 650 and an '80 XS750 and both of them were set up that if you put oil in the schrader valve, no problems, your just using the valves to pressurize the internals, oil and all. End of my experience. Go forth and fill...just don't put too much in like Nacho said. You WILL blow seals that way.

 

I know that this post was a long time ago, but I have an 82 XJ650J with Air Assist forks, A local shop about a year ago rebuilt them, they were my spare set off of my spare parts bike, so I didn't use them right away, when pulling out my bike this year and going for a quick ride my Front seals were leaking so I threw the rebuilt spares on her. But I noticed even after making sure she has enough Air pressure that she is very bouncy which makes me believe the @$$#@!3$ didn't replace/fill the oil when they rebuilt them. Is there a way I can quickly/easily replace/or actually fill them without taking them apart?

 

You just need to take the caps off and ad oil. It may be easier to take the handlebars off but theres no need to remove the forks just to put the oil in.

 

If you took just the forks to a shop to have them rebuilt, I would expect them to have NOT filled them with oil. They would have expected you to do that once reinstalled on the bike.

Carefully remove the drain plugs and pump them (over a pan, just in case) to remove any trace amounts of oil that might be in there from the rebuild; then replace the drain screws, open the caps and add the recommended amount of fork oil. Yamaha forks generally respond well to the use of 15W rather than the recommended 10W.

 

What caps, the only caps on there cover the Air fill valve?,

Usually Bigfitz I look forward to and appreciate your help, but...

If you are rebuilding forks because they are leaking the common sense thing would be to fill them with oil. So the disrespectful way you typed was not needed.
Oh and the Service manual is not clear on changing/filling the oil except when you are rebuilding the forks, then it tells you to fill them when you have them apart, again... I would ASSUME that if the service manual tells you to do that during the rebuild while it is apart then one would ASSUME that the "COMMON SENSE" thing to do as the mechanic doing the work would be to fill them, While they are apart.
The service manual does not show a fill port and again the only "cap" is the cheap plastic one covering the Air Fill Valve.

Also apparently no-one read "richard03" post about the shop telling him that it is the wrong way to fill them. hence why I asked my question...

 

to me it looks like bigfitz was helping you

 

Move the Bars out of the way.
The whole Schrader Air Valve can be removed.
Not just the Core of the Valve.
The whole thing.

When you get the Valve out collect the O-ring.
Buy an Ear Syringe.
Measure the right amount of fork oil into a clean jar.
Fill the syringe.

Fill the Fork.