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Change fork fluid and seals w/out removing top cap

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Somebody pls tell me why I can't do this on my 07. I removed the rebound bolt, drained the oil, pulled the fork legs apart, then put in new oil in the upper leg while it was upside down, and reassembled with new seals and dust covers. My local shop said it can't be done that way. Just wondering why. And can I add the new oil thru the lug before I put the rebound bolt back on?

Thanks

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Why wouldn't you just remove the damper? I don't know why it wouldn't work, but I've never done it like that.

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Removing the damper is just another step. I just had the forks revalved, then the right oem seal blew out while riding shortly after. So if I don't need to change the oil in the inner chamber, why remove the top cap and damper?

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Removing the damper assembly doesn't require changing the damper oil. The damper oil is the only tricky part of the job (IMO). Removing the whole damper assembly would have likely made this job easier and cleaner. What you did may be similar to draining engine oil through the fill hole by inverting. Would probably work, but why?

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Why? Because not removing the top cap and damper saves a step and time. Why would it make it easier by removing the top cap and damper? I'm not saying you're wrong. I'm just curious.

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This actually sounds like a really good idea, I may have to try this as I need to replace my seals this week.

I do not fully understand how you do it though. Do you just undo the bolt at the bottom and then do everything as you would normally without pulling the top of the fork apart?

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And I too am not trying to be critical. I have a hard time picturing how this went for you. You loosen the rebound adjuster, push on fork, and insert stopper tool. Doesn't oil shoot all over the place? So then you must've left the stopper tool in place as you re-filled, right? Was it hard to get the oil in?

I loosen damper, pull big tube down, dump oil, re-thread damper, then resume presumably as you did. Although I presume it is much easier to add the oil when done this way.

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sam: Exactly. I didn't pull the top cap off the upper leg.

emery: It went the same as the usual process, i just saved a step. When i had the fork legs apart, i poured the oil in the upper leg while it was upside down. Basically poured it in where the seal is. No oil shot anywhere when I pushed on the lower leg to insert the 13mm wrench to hold the rod and remove the rebound adjuster. Pouring the oil in while the legs are apart is like pouring oil in a bucket. Piece of cake.

Again: With fork upside down and topcap untouched and bleeder screw in, remove rebound bolt, remove rebound adjuster from rod, remove stopper tool, pour out outer chamber oil (careful to catch the rod), bang bang bang to get legs apart, pull out spring, pour in oil where the spring just was, replace spring, put wiper, seal, washer, bushing on lower leg, then reassemble. Money.

Now, if all I'm doing is changing the fluid, I would remove rebound bolt and adjuster and stopper tool, pour out oil, pour in oil, reassemble.

Someone pls tell me why I can or can't do this.

Thanks

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It works, I have done it, but I prefer to do it the normal way.

E.

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Thanks 801. My only fear was bleeding/burping issues from pouring in the fluid from the middle or bottom.

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How about a more important question. Why change only the outer chamber fluid, if the fork seal isn't being replaced? I've heard of doing a fork seal replacement, and therefore needing to change the outer chamber, but without needing to do the inner.

Is removing the top cap really any harder than removing the bottom? :)

ben

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Isn't it little hard to get the seal out and separate the upper/lower tubes with the spring tension on the forks? It's easy to unscrew the inner chamber and remove without needing to open it and change oil. If I'm just changing a seal, sometimes don't even mess with inner oil, depending on how long it's been. Just seems so easy to remove seals when you can slide the legs easily to hammer out seal.

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Op wanted to know if it is possible to replace a seal with out removing the fork cap. Yes it is, but I prefer to take the forks apart to inspect everything. I also change all the suspension fluid every 3 months, and replace seals every 6.

E.

There are no bleeding issues, bleed them as the owners manual says.

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I guess if you don't have a 50mm wrench laying around this could be worth considering. I do have one though.

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Ben: If I'm just doing oil, the top cap is fine too. In the past when I've been in a time crunch, I have actually left the forks on the bike and drained thru the bottom and filled thru the top via removing the topcap using tiedowns to compress the forks.

susco: The spring doesn't come into play really once u remove the rebound bolt and adjuster. Not sure how you'd replace the seals w/out separating the legs. You'd have to remove the lug. Too much work.

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The only problem that I could see in doing it this way is making sure that you have removed all of the oil from the chamber that the ICS spring is in. If you can be 100% certain that all of the oil and any contamination is out than you should be fine doing it the way that you described, I don't see how that is possible, but I am no expert. What are the tie downs for?

Personally I like to inspect and clean everything inside my forks, so I choose to do it the more conventional way.

Dan

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The tiedowns are to compress the forks which raises the topcap so you can pour in fluid.

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Ben: If I'm just doing oil, the top cap is fine too. In the past when I've been in a time crunch, I have actually left the forks on the bike and drained thru the bottom and filled thru the top via removing the topcap using tiedowns to compress the forks.

susco: The spring doesn't come into play really once u remove the rebound bolt and adjuster. Not sure how you'd replace the seals w/out separating the legs. You'd have to remove the lug. Too much work.

Sorry, I still just don't get it. Why do you need to change the outer chamber fluid, if you are not changing the fork seals. About the only time I'll do only the outer chamber is if I had just very recently serviced the forks and suddenly have a fork seal that is leaking. And only then, will I skip the inner chamber after I've inspected that it is operating correctly. For example, compressing and rebounding fully and smoothly.

You are not going to get any performance gains by just doing the outer chamber. If your outer chamber fluid needs to be changed due to number of hours, then so does the inner chamber. The inner chamber is much more key to the overall performance.

If you are tight for time, just ride the damn thing with the oil that is in it. Then later service it correctly.

People wonder why their fork seals leak, bushings are trashed, etc. If you ride every weekend, you should be servicing the suspension fluid about every 3 months. At the most, every 6 months. The more often you do it, the less often you'll need parts like seals and bushings.

ben

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If you have a leaky seal, you very likely have dirt or garbage in there. I prefer to have the tubes wide open and flush them out 100% - did the '09 today. I wouldn't trust me to get the closed end clean enough so the very minor extra step is actually a requirement IMO. I'm starting to enjoy doing suspension work. I have some RaceTech vise jaws that really help speed it up. Been seriously thinking about the MotionPro Soft Jaw device, but haven't pulled the trigger on that one yet.

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