Fork seals?


13 replies to this topic
  • finthat

Posted February 15, 2009 - 09:14 PM

#1

How hard is it to change the fork seals? I have a 03 450 and it needs them. I can do most other jobs right down to engine rebuild, have never tried fork seals. Anything special needed or should I just take them in to a pro?

  • WR450FGreg

Posted February 15, 2009 - 10:42 PM

#2

.
I did my own '08 forks recently.

From memory it was all standard home workshop tools apart from:

1. A home made damper rod holder. Which is basically a piece of tube cut with a "castle" pattern on one end. (Check your manual, there should be a diagram of it.)

2. 1/2" socket drive allen key (can't recall the size, maybe 8mm?) with air impact (or "rattle") gun. You may get away with a hand held impact driver, but the air gear makes it a hell of a lot easier.

3. You could make a seal driver if you like but I got away without that.

Follow the instructions in your manual.

Good luck!
Greg

  • grayracer513

Posted February 15, 2009 - 10:51 PM

#3

Removing the damper/base valve from the lower fork leg is completely unnecessary for the purpose of changing fork seals. The purchase of a real seal driver is highly recommended. Motion Pro is about $60.

  • finthat

Posted February 16, 2009 - 11:45 AM

#4

Thanks guys I think I will give it a try. If all else fails I'll just take them in to the local suspension guru.

  • WR450FGreg

Posted February 16, 2009 - 10:16 PM

#5

.

Removing the damper/base valve from the lower fork leg is completely unnecessary for the purpose of changing fork seals.


I just followed the instructions!
I guess you are right Gray, but why go to the trouble of replacing the seals without pulling the forks apart and cleaning all traces of the old oil out thoroughly first? The forks are off the bike anyway. :lol:

Call me fussy, but I like to do things right the first time.

Greg

  • grayracer513

Posted February 17, 2009 - 07:22 AM

#6

.
why go to the trouble of replacing the seals without pulling the forks apart and cleaning all traces of the old oil out thoroughly first?

Pumping clean mineral spirits through the fork, then washing that out with some new oil has always worked fine for me. The idea that a "trace" of old oil is somehow harmful is a little silly, since if the fork hadn't leaked you would probably have left it there, and if you think that a shop always does a full tear down for seals, you might want to hang around and watch once. If the fork is full of crud from running the same oil for 3 years, that's one thing, but most of the time, it simply isn't necessary. You can, of course, do so if you like.

  • finthat

Posted February 18, 2009 - 04:24 PM

#7

Should have new seal kit by tomorrow and will attempt the seal change this weekend. Where does a guy get mineral spirits?? Is there a brand name for it or is it just mineral oil?? I am asuming brake cleaner or a solvent is way to harsh to flush with. Thanks again guys for the tips.

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  • grayracer513

Posted February 18, 2009 - 05:02 PM

#8

Mineral Spirits is available at most any hardware or paint store, and is more similar to paint thinner. It isn't an oil. Brake/Carb cleaner will work, but it costs far more. Drain what oil you can, pour 10-12 ounces of MS into the lower tube, damper assembly and work it through some. Pump it out and drain it.

Just before you assemble the fork, pour about 6-8 ounces of your new oil into the assembly and do the same thing with it to chase out the remaining solvents. You'll need just over two quarts to fill your forks anyway, so you'll have enough.

  • TeamPrecisionIT

Posted May 07, 2009 - 03:17 PM

#9

Instead of making a new thread, I'll go ahead and add to this one and sort of necropost.

Anyway, after I replaced my fork seals and was going to get the fork oil back into my right fork leg, the damn thing won't suck in any oil. It's almost like the valving is blocked or something to that affect. I am thinking I need to take out the base valve and check it out to see if anything is down there blocking the passage of oil.

Also, the reason I think this is the case, is because last time I replaced my fork seals I noticed the spring guide had cracked and a couple pieces of it had broken off. This last time I replaced my fork seals, I went ahead and obviously replaced the broken spring guide, but even though I have flushed my forks quite a bit, there are still small pieces of the plastic guide rod coming out in the oil. The new one is still intact and fine.

My main question lies in the fact that I don't have a damper rod holder, nor do I know, or could find a good explanation on, how to make one. Do I really need it when I use an impact or should I make one before going at the base valve with an impact?

Damian

  • TeamPrecisionIT

Posted May 07, 2009 - 06:01 PM

#10

Pumping clean mineral spirits through the fork, then washing that out with some new oil has always worked fine for me.


I just tried this but it didn't work for my problem. I still have a lack of valving going on. I am going to take my fork to work tomorrow so that I can maybe use an impact there and try to get the base valve cleaned up. Is there anything I need to know if particular about taking the base valve off?

Damian

  • grayracer513

Posted May 07, 2009 - 07:57 PM

#11

You'll need a cartridge holder, or at least an impact wrench. once it's out, it will need to be disassembled. It's probably got frags jammed in it. You might consider having this done.

  • tnl

Posted May 07, 2009 - 08:28 PM

#12

I just serviced mine recently for the first time and I used a $10 pipe clamp with a 4 foot pipe from lowes to compress and hold the damping assembly and it worked great. I also used it to presss in my swing arm bearings and it's a good tool to have in the garage for a million other things.

  • gbalias

Posted May 08, 2009 - 12:09 AM

#13



  • CaptainKnobby

Posted May 08, 2009 - 06:10 AM

#14

Removing the damper/base valve from the lower fork leg is completely unnecessary for the purpose of changing fork seals. The purchase of a real seal driver is highly recommended. Motion Pro is about $60.


But since you have your forks off and more than likely if you are replacing the seals you will probally want to change the oil and would want to take the damper/basevalve out to change the oil in there.

BTW grey all my tools have came in that I ordered for the forks and also I ordered the Motion pro soft jaw vice, it should be here monday.

I know the manual word for word and like the back of my hand now about the forks. One thing I see in the manual that they didnt mention is when you take the adjuster off on the bottom of the innertube,they say nothing about taking the pushrod out from the damper assy. WHY?

This could confuse some people when they work on ther forks and didnt do any research beforehand like Iam doing. When someone got to this part and seen this rod they would know nothing about it cause it never mentions it in the manual for the 06450f. I guess they just assume you should know since you are working on forks.





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