Changing fork oil, need a little help.

[JasonfromMN]

08 TE 450

Changing the fork oil VIA the Dirtbike mag article! Oh crap, these are nothing like the ones in that article!!!

Anyone done this yet? Oils out, too late to turn back!

Im assuming I just need to pump the inner tub until I can see the air is mostly out and keep it full of oil when I put the cap back on, but I cant get the spring out!?

Then fill the outer tube to the amount that came out?(I measured it)

Please advise......

 

[Dirtdame]

The damper rod is pumped until no more oil comes out and you can't feel the resistance of oil in the lower cartridge when you are pumping it. Then you stand the fork leg up collapsed and put fresh oil in, pump the rod until all the air is bled out and finish filling the fork with oil to about 100-110 mm from the top (make sure each side is the same). Then you can extend the fork, pull the rod up and reinstall your spring.

 

[JasonfromMN]

The damper rod is pumped until no more oil comes out and you can't feel the resistance of oil in the lower cartridge when you are pumping it. Then you stand the fork leg up collapsed and put fresh oil in, pump the rod until all the air is bled out and finish filling the fork with oil to about 100-110 mm from the top (make sure each side is the same). Then you can extend the fork, pull the rod up and reinstall your spring.

Are you referring to the inner tube or the outer? If its the inner, doesn't it need to be filled and pumped until all the air is out(after pumping until all the old oil is out), filled to being overspilling and then put the bottom cap back on? Then turn it right side up and fill the outer tube to the 100-110mm from the top?

Also, I do not know how to get the spring out to be able to pump the damper rod. I do need to get the spring out first don't I?

Thanks.

 

[Dirtdame]

Remove the cap from the rod. You will need a wrench to fit on the blue anodized nut through the spring coils, then you can get the wrench you need onto the cap nut and remove the cap. Then the spring will come off. Then you can grab the rod and pump the oil out. Pumping the outer tube won't remove all the oil. When no more oil comes out and there is no resistance when you pump the rod, the cartridge is bled.

 

[JasonfromMN]

Ok makes sense. Then to refill? How much oil goes into the inner cartridge? When I removed the lower cap- for the inner cartridge, I remember the oil not being all the way up to the top threads?(on the bottom) Is that where the 100-110 mm comes into place? or was that for the outer cartridge?

Sorry, forks are not my strong point...

 

[Dirtdame]

Ok makes sense. Then to refill? How much oil goes into the inner cartridge? When I removed the lower cap- for the inner cartridge, I remember the oil not being all the way up to the top threads?(on the bottom) Is that where the 100-110 mm comes into place? or was that for the outer cartridge?

Sorry, forks are not my strong point...

Probably you need some pictures.....stop whatever you are doing to your forks and either take them to a suspension specialist and have them work on them, or find somebody who can show you what you need to do in person.

 

[JasonfromMN]

Your probably right. Thanks for the help you've offered.

 

[ghte]

Mate jump onto Rocky Mountain ATVMM web site and hit their "video" link on the home page. A brilliant 2 part video of open cartridge (one on twin cartridge as well) fork seal replacement and oil replacement. Watch it twice then go for it tiger. I must congratulate Rocky Mountain these videos are just brilliant.

 

[JasonfromMN]

Ahhhhh. No wonder I kept referring to inner and outer and dirtdame didn't. There is no inner and outer. Its all one, I just pulled the bottom cap when I shouldn't have. Time to go out and put that cap back on and try again. Thanks!

 

[JasonfromMN]

All is well with the world! Ok, maybe just my forks. Thanks for the help!

I'll do a write up on what I did when I get a bit more time tonight. It was really easy once I watched that video and realized what type of forks I have.

 

[glangston]

http://www.husqvarnaracingclub.cz/ohqv_manualy.html

Can download the manual for them here..

 

[JasonfromMN]

First things first, The 08 TE 450 forks are not the same as the ones featured in the dirtbike mag article. I think the ones in the dirtbike/Marzoochi artical are called twin chamber forks. The ones I have are cartridge forks.

What I did wrong was that I removed the bottom nut like the article said. In these forks you don't typically do that, because your supposed to be able to drain all the fluid out through the top, while pushing and pulling lightly on the damper rod. Ended up that Im glad that I made that mistake, and will continue to do so next time because on the second fork tube that I tried to drain w/o removing the lower nut, I did not get as much fluid out as the first. Even though I pumped the crap out it, I still couldnt get all the oil out. On the first(mistake) one, after I removed the bottom nut(valving) I was able to drain out all the oil directly from the lower part of the cartridge. Unlike the article forks which has 2 seperate chambers, mine has an upper and lower part to the cartridge but they share the same oil. I didn't end up filling the lower part first like I thought, but assembled it, turned it right side up and then filled it about 3/4 way(of correct amount of oil, not just to the top), pumped the damper rod lightly until the action is smooth(air out) and then filled it up the rest of the way.(correct amount) My thoughts are, if I cant get all the oil out, no point in doing it at all because it would just contaminate the new oil.

I am certainly NOT a fork man, but I have done a style like this before and needed to realize which style I had for it to make sense to me. I would NOT RECOMEND anyone to follow what I have done. With that said, I will still list in order what I did and will do the next time around.

1- loosen top cover with forks in the clamps 2- Remove forks from clamps 3- remove top cover and let the outer tube slide down. 4- Unscrew top cover from damper rod, and then the push rod from the inside of the damper rod . 5- remove spring. 6- Pour out old oil into a measuring device while slowly pumping damper rod.(they claim you can get all the oil out just doing this) 7-(for me to get more oil out) remove lower valve nut with impact wrench. 8- Now I can remove entire innerds from the outer tube and dump the remaining oil out from the lower section of the cartridge. 9- Put back in "innerds" and hand tigten the lower valving nut. 10- With fork tube collasped, pour in 3/4 of the correct amount of oil. 11- slowly push in and pull out the damper rod untill it doesn't make funny noises and feels smooth. 12- pour in the rest of the correct amount of oil. 13- replace push rod inside the damper rod and then the spring. 14- Pull up on the damper rod assemble through the spring until you can get a few threads to go on the top cap. 15- tighten the top cap to the damper rod, then screw it back onto the outer tube.(not collapsed at this point) 16- Then what I did to final tighten the lower valving nut was a bit tricky but- with the socket on the impact wrench on the floor, I set the assembled fork(lower nut of course) into the socket, then apply a little pressure to the top of the fork and tap the impact wrench trigger until the whole fork wants to spin. That tells me its tight. I did not use a torq wrench on this because it will spin on the inside. However, Im not worried because this lower valving nut has an o ring on it, I just didnt want to get it too tight nor too loose so as to leak. 17- get the oil level exactly even on both fork legs. 18- Lastly, I turned both compression and rebound clickers into its seated position, then 10 clicks out each for a new starting point.

Observations:

When I poured out the old oil after removing the spring, a large spacer will fall out. No biggie, it just goes back in before I put the spring in.

The oil in my measuring cup looked light on the top half, and dark/dirty on the bottom half.

The oil in the first fork seemed thick almost like gear oil, not dirtier, just thicker. The second fork oil seemed very thin, more like gas. No wonder I felt I had problems.

I CAN change the spring preload on these by adding a proper sized washer between the top spring bushing and the top cap.(damper rod has to go through the center of the washer)

I used 5wt oil

Then it was go time. Also first time with my new PU KIT! First impressions are GOOD. My ride was short and only in my ditch and will need A good extended ride this weekend to readjust the clickers, and possibly the oil level. I am experimenting with a different oil level.

Notice I said "I" everywhere and not "YOU". I don't recommend doing this to anyone and my methods could be completely wrong. Just thought I'd share what I ended up doing.

Thanks for those who tried to help the helpless and for the Fork link.

 

[JasonfromMN]

I posted this in the suspension dept of TT. Thought Id post it here as well to see what you folks think. Still trying to work out a stiff initial and mid stroke issue.

Tonight I decided to disassemble the forks to try and understand whats going on inside them with the valving. Im posting some pic's of the guts, hopping someone can explain what some of these parts are and what they specifically do. As far as my last post, I don't think binding is a problem. Their is no sign of it with wear on any of the parts.

This is the valving in the bottom of the fork tube.(shims in the middle) Is it for compression or rebound? I assume its for compression because the rebound push rod at the top seems to rest against some valving at the mid point?

[/IMG]
This is what it looks like disassembled. All these washers seem to have the same thickness, but different diameters? Can this be changed? can I remove or change one of them for a softer initial stroke? Am I way off? Can anything be changed with this? Any thing else you can tell me about this?

This is the base valve cap. What ACTUALLY happens when I turn the screw? The plunger in the center moves forward.

This is looking into the the bottom tube that the base valve screws into. What can you tell me about this? Am I looking at the mid valve?

[/IMG]
This piece?

How bout this one?

Heres all the parts inside the fork. Any comments on what they are or what they do?(except for the obvious)

With all the parts shown, is their anything I can do to make the compression softer on the early part of the stroke? Anything with the shims?

Thanks for reading. Jason.

 

[Dirtdame]

Probably not going to find anybody who will give a away their formula for shim stacking.

You would also need to stack the shims so that the dampening tightens up deeper in the stroke. That's how I had mine done, stacked to be plush at the beginning of the stroke for rocky areas and stiffer deeper in the stroke for big whoops, and a higher oil level too. And no, I don't feel like disassembling my forks and reading all my shims thicknesses and diameters.

 

[ray_ray]

Way to late for this but I removed sag from my front forks a few days ago and it seemed like it helped the first few inches of travel become a lot more plush ... i'm thinking my forks were sagging past the stroke of forks .... I have the marzocchi 50mm forks with the dual chambers though ...

I'm playing with some different oils also as I was supplied with an article that was very interesting on the subject of suspension fluids ..

http://www.pvdwiki.com/index.php?title=Suspension_Fluid ... Oil is just oil with a few additives added

 

[JasonfromMN]

Im not looking for anyones secret valving formulas. Just want to learn what I can start experimenting with to hopefully arrive at my own someday. But I first need to learn what everything does and what changes i can make that affects what.

Ray Ray, I cannot add sag to my forks like yours unless I cut down a factory sized preload block that would be permanent. I have played with oil level and WT with no success. I either will learn how to change the valving myself, or send it out to a suspension shop to be done with money and time that I dont have now. The thing that hangs me up on that is- I could send it out, pay lots $, and still not like it or need to tweak a little. For now Im determined to find a combo myself with only time and $ in oil. Besides, how to learn and do this stuff ourselves!

BTW, if I end up with a formula that I think works, I will certainly post It!

 

[ray_ray]

Nice thread here ESP if you can get some tips from others ;0 ) Too bad you can't ADJ that pre-load easily .... These Marozcchi have small clips that you can move up and down easily for pre-load ..U don't even have 2 drain the oil out ...

It is seeming like oil WTS are just changing the feel of the forks' stroke ... Lighter oil, easier stroke...heavier oil, slower stroke overall ... The valving still controls the real action of the forks ....

Yep, totally see UR point on the $ and re-valving I just don't have the jack for it

 

[redbone]

Most good suspension shops that do revalving will revalve until your happy with it. I'm sure theres a certain cut off point though. Bruce Triplett at www.brucessuspension.com isn't happy till your happy. His website has some great info on it, check it out.

 

[ray_ray]

Yep, nice site ... I gotta read his tips a few more times to get all of it to sink in

 

[JasonfromMN]

Great site! Really helps while all my shim stacks are laying across my garage table! Makes things make more sense.

Heres whats going on- I removed all my shim stacks, measured them with a dial caliper and posted them on TT, on the first fork only. I left the other fork for a reference in case I goof.

Someone noticed the shims order didn't look normal and asked if I could have gotten them flipped around. Don't think I did but anythings possible. Learned a bit more about the parts, then tonight I removed the other forks base valve to compare shim stacks to see if they were consistent with the first ones. They aren't!! I did not get them flipped around because the shims were so out or order I would have had to drop them all over the floor and try to guess their order. So I definitely have a problem with the 2 forks being consistent in base valve shim stacking. I haven't pulled the second mid valve stack yet to compare and will do that tonight if I get a chance. I also talked to a suspension tuner tonight, with that and TT should have a base to start with.